The process in certain BACTERIA; FUNGI; and CYANOBACTERIA converting free atmospheric NITROGEN to biologically usable forms of nitrogen, such as AMMONIA; NITRATES; and amino compounds.
An enzyme system that catalyzes the fixing of nitrogen in soil bacteria and blue-green algae (CYANOBACTERIA). EC 1.18.6.1.
The relationship between two different species of organisms that are interdependent; each gains benefits from the other or a relationship between different species where both of the organisms in question benefit from the presence of the other.
Knobbed structures formed from and attached to plant roots, especially of LEGUMES, which result from symbiotic infection by nitrogen fixing bacteria such as RHIZOBIUM or FRANKIA. Root nodules are structures related to MYCORRHIZAE formed by symbiotic associations with fungi.
A genus of gram-negative, aerobic, rod-shaped bacteria that activate PLANT ROOT NODULATION in leguminous plants. Members of this genus are nitrogen-fixing and common soil inhabitants.
A species of gram-negative, aerobic bacteria that causes formation of root nodules on some, but not all, types of sweet clover, MEDICAGO SATIVA, and fenugreek.
A family of gram-negative bacteria which are saprophytes, symbionts, or plant pathogens.
The positioning and accommodation of eyes that allows the image to be brought into place on the FOVEA CENTRALIS of each eye.
Stable nitrogen atoms that have the same atomic number as the element nitrogen, but differ in atomic weight. N-15 is a stable nitrogen isotope.
A plant genus of the family FABACEAE. This genus was formerly known as Tetragonolobus. The common name of lotus is also used for NYMPHAEA and NELUMBO.
A genus of gram-negative, aerobic bacteria found in soil and water. Its organisms occur singly, in pairs or irregular clumps, and sometimes in chains of varying lengths.
The functional hereditary units of BACTERIA.
The circulation of nitrogen in nature, consisting of a cycle of biochemical reactions in which atmospheric nitrogen is compounded, dissolved in rain, and deposited in the soil, where it is assimilated and metabolized by bacteria and plants, eventually returning to the atmosphere by bacterial decomposition of organic matter.
An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
A plant species of the family FABACEAE widely cultivated for ANIMAL FEED.
The formation of a nitrogen-fixing cell mass on PLANT ROOTS following symbiotic infection by nitrogen-fixing bacteria such as RHIZOBIUM or FRANKIA.
A family of signal transducing adaptor proteins that control the METABOLISM of NITROGEN. They are primarily found in prokaryotes.
The use of metallic devices inserted into or through bone to hold a fracture in a set position and alignment while it heals.
A species of gram-negative, aerobic bacteria that is found in soil and which causes formation of root nodules on some, but not all, types of field pea, lentil, kidney bean, and clover.
A species of gram-negative bacteria and nitrogen innoculant of PHASEOLUS VULGARIS.
A genus of gram-negative, aerobic, rod-shaped bacteria usually containing granules of poly-beta-hydroxybutyrate. They characteristically invade the root hairs of leguminous plants and act as intracellular symbionts.
A form-genus of unicellular coccoid to rod-shaped CYANOBACTERIA, in the order Chroococcales. Three different clusters of strains from diverse habitats are included.
Proteins found in any species of bacterium.
A hemoglobin-like oxygen-binding hemeprotein present in the nitrogen-fixing root nodules of leguminous plants. The red pigment has a molecular weight approximately 1/4 that of hemoglobin and has been suggested to act as an oxido-reduction catalyst in symbiotic nitrogen fixation.
A species of gram-negative, aerobic bacteria first isolated from soil in Vineland, New Jersey. Ammonium and nitrate are used as nitrogen sources by this bacterium. It is distinguished from other members of its genus by the ability to use rhamnose as a carbon source. (From Bergey's Manual of Determinative Bacteriology, 9th ed)
Gram-negative, non-motile, capsulated, gas-producing rods found widely in nature and associated with urinary and respiratory infections in humans.
The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)
A phylum of oxygenic photosynthetic bacteria comprised of unicellular to multicellular bacteria possessing CHLOROPHYLL a and carrying out oxygenic PHOTOSYNTHESIS. Cyanobacteria are the only known organisms capable of fixing both CARBON DIOXIDE (in the presence of light) and NITROGEN. Cell morphology can include nitrogen-fixing heterocysts and/or resting cells called akinetes. Formerly called blue-green algae, cyanobacteria were traditionally treated as ALGAE.
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
A plant species of the family FABACEAE used to study GENETICS because it is DIPLOID, self fertile, has a small genome, and short generation time.
A genus of CYANOBACTERIA consisting of trichomes that are untapered with conspicuous constrictions at cross-walls. A firm individual sheath is absent, but a soft covering is often present. Many species are known worldwide as major components of freshwater PLANKTON and also of many saline lakes. The species ANABAENA FLOS-AQUAE is responsible for acute poisonings of various animals.
Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.
The technique of using FIXATIVES in the preparation of cytologic, histologic, or pathologic specimens for the purpose of maintaining the existing form and structure of all the constituent elements.
A plant genus in the family FABACEAE which is the source of edible beans and the lectin PHYTOHEMAGGLUTININS.
The large family of plants characterized by pods. Some are edible and some cause LATHYRISM or FAVISM and other forms of poisoning. Other species yield useful materials like gums from ACACIA and various LECTINS like PHYTOHEMAGGLUTININS from PHASEOLUS. Many of them harbor NITROGEN FIXATION bacteria on their roots. Many but not all species of "beans" belong to this family.
An enzyme that catalyzes the conversion of ATP, L-glutamate, and NH3 to ADP, orthophosphate, and L-glutamine. It also acts more slowly on 4-methylene-L-glutamate. (From Enzyme Nomenclature, 1992) EC 6.3.1.2.
Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.
Inorganic compounds that contain nitrogen as an integral part of the molecule.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
Nitrate reduction process generally mediated by anaerobic bacteria by which nitrogen available to plants is converted to a gaseous form and lost from the soil or water column. It is a part of the nitrogen cycle.
A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.
A species of gram-negative bacteria in the genus PSEUDOMONAS, containing multiple genomovars. It is distinguishable from other pseudomonad species by its ability to use MALTOSE and STARCH as sole carbon and energy sources. It can degrade ENVIRONMENTAL POLLUTANTS and has been used as a model organism to study denitrification.
A genus of gram-negative, rod-shaped bacteria in the family PHYLLOBACTERIACEAE. They are able to invade root-hairs of a wide range of plants, inciting the production of PLANT ROOT NODULES.
The urea concentration of the blood stated in terms of nitrogen content. Serum (plasma) urea nitrogen is approximately 12% higher than blood urea nitrogen concentration because of the greater protein content of red blood cells. Increases in blood or serum urea nitrogen are referred to as azotemia and may have prerenal, renal, or postrenal causes. (From Saunders Dictionary & Encyclopedia of Laboratory Medicine and Technology, 1984)
Nitrogen oxide (NO2). A highly poisonous gas. Exposure produces inflammation of lungs that may only cause slight pain or pass unnoticed, but resulting edema several days later may cause death. (From Merck, 11th ed) It is a major atmospheric pollutant that is able to absorb UV light that does not reach the earth's surface.
A non-heme iron-sulfur protein isolated from Clostridium pasteurianum and other bacteria. It is a component of NITROGENASE, which is active in nitrogen fixation, and consists of two subunits with molecular weights of 59.5 kDa and 50.7 kDa, respectively.
A metallic element with the atomic symbol Mo, atomic number 42, and atomic weight 95.94. It is an essential trace element, being a component of the enzymes xanthine oxidase, aldehyde oxidase, and nitrate reductase. (From Dorland, 27th ed)
Specialized devices used in ORTHOPEDIC SURGERY to repair bone fractures.
The cycle by which the element carbon is exchanged between organic matter and the earth's physical environment.
A genus of gram-negative, aerobic, nonsporeforming rods which usually contain granules of poly-beta-hydroxybutyrate. (From Bergey's Manual of Determinative Bacteriology, 9th ed)
A non-heme iron-sulfur protein isolated from Clostridium pasteurianum and other bacteria. It is a component of NITROGENASE along with molybdoferredoxin and is active in nitrogen fixation.
The functional genetic units of ARCHAEA.
Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.
The synthesis by organisms of organic chemical compounds, especially carbohydrates, from carbon dioxide using energy obtained from light rather than from the oxidation of chemical compounds. Photosynthesis comprises two separate processes: the light reactions and the dark reactions. In higher plants; GREEN ALGAE; and CYANOBACTERIA; NADPH and ATP formed by the light reactions drive the dark reactions which result in the fixation of carbon dioxide. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)
A genus in the family ACETOBACTERACEAE comprised of acetate-oxidizing bacteria.
Deoxyribonucleic acid that makes up the genetic material of bacteria.
Nitrogenous products of NITRIC OXIDE synthases, ranging from NITRIC OXIDE to NITRATES. These reactive nitrogen intermediates also include the inorganic PEROXYNITROUS ACID and the organic S-NITROSOTHIOLS.
One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.
The relationships of groups of organisms as reflected by their genetic makeup.
Implantable fracture fixation devices attached to bone fragments with screws to bridge the fracture gap and shield the fracture site from stress as bone heals. (UMDNS, 1999)
A variable annual leguminous vine (Pisum sativum) that is cultivated for its rounded smooth or wrinkled edible protein-rich seeds, the seed of the pea, and the immature pods with their included seeds. (From Webster's New Collegiate Dictionary, 1973)
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A species of AZORHIZOBIUM which forms nodules on the roots of the tropical legume Sesbania rostrata. (From Bergey's Manual of Determinative Bacteriology, 9th ed)
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
In bacteria, a group of metabolically related genes, with a common promoter, whose transcription into a single polycistronic MESSENGER RNA is under the control of an OPERATOR REGION.
An annual legume. The SEEDS of this plant are edible and used to produce a variety of SOY FOODS.
A species of motile, free-living, gram-negative bacteria that occur in the soil. They are aerobic or microaerophilic and are sometimes capable of nitrogen fixation.
An order of insects, restricted mostly to the tropics, containing at least eight families. A few species occur in temperate regions of North America.
A genus of gram-negative, strictly aerobic, non-spore forming rods. Soil and water are regarded as the natural habitat. They are sometimes isolated from a hospital environment and humans.
Total mass of all the organisms of a given type and/or in a given area. (From Concise Dictionary of Biology, 1990) It includes the yield of vegetative mass produced from any given crop.
The salinated water of OCEANS AND SEAS that provides habitat for marine organisms.
A plant genus of the family FABACEAE. Members contain piperidine alkaloids (PIPERIDINES).
Non-pathogenic ovoid to rod-shaped bacteria that are widely distributed and found in fresh water as well as marine and hypersaline habitats.
External devices which hold wires or pins that are placed through one or both cortices of bone in order to hold the position of a fracture in proper alignment. These devices allow easy access to wounds, adjustment during the course of healing, and more functional use of the limbs involved.
Agents employed in the preparation of histologic or pathologic specimens for the purpose of maintaining the existing form and structure of all of the constituent elements. Great numbers of different agents are used; some are also decalcifying and hardening agents. They must quickly kill and coagulate living tissue.
A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.
The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.
Geological formations consisting of underground enclosures with access from the surface.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
New immature growth of a plant including stem, leaves, tips of branches, and SEEDLINGS.
The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.
Genus of BACTERIA in the family Frankiaceae. They are nitrogen-fixing root-nodule symbionts of many species of woody dicotyledonous plants.
A plant genus of the family FABACEAE. It is distinct from Sweet Clover (MELILOTUS), from Bush Clover (LESPEDEZA), and from Red Clover (TRIFOLIUM).
The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.
A genus of gram-negative aerobic bacteria that occurs free-living in the soil or associated with the roots of cereal crops or grasses (POACEAE).
Inorganic oxides that contain nitrogen.
The use of nails that are inserted into bone cavities in order to keep fractured bones together.
A class in the phylum PROTEOBACTERIA comprised mostly of two major phenotypes: purple non-sulfur bacteria and aerobic bacteriochlorophyll-containing bacteria.
A plant genus of the family FABACEAE that is widely used as ground cover and forage and known for the edible beans, VICIA FABA.
Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Mutagenesis where the mutation is caused by the introduction of foreign DNA sequences into a gene or extragenic sequence. This may occur spontaneously in vivo or be experimentally induced in vivo or in vitro. Proviral DNA insertions into or adjacent to a cellular proto-oncogene can interrupt GENETIC TRANSLATION of the coding sequences or interfere with recognition of regulatory elements and cause unregulated expression of the proto-oncogene resulting in tumor formation.
A plant genus of the family BETULACEAE that is distinguished from birch (BETULA) by its usually stalked winter buds and by cones that remain on the branches after the small, winged nutlets are released.
The genetic complement of a BACTERIA as represented in its DNA.
The complete absence, or (loosely) the paucity, of gaseous or dissolved elemental oxygen in a given place or environment. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Life or metabolic reactions occurring in an environment containing oxygen.
Devices which are used in the treatment of orthopedic injuries and diseases.
A form-genus of CYANOBACTERIA in the order Nostocales. Trichomes composed of spherical or ovoid vegetative cells along with heterocysts and akinetes. The species form symbiotic associations with a wide range of eukaryotes.
A genus of gram-negative, curved and spiral-shaped bacteria found in stagnant, freshwater environments. These organisms are motile by bipolar tufts of flagella having a long wavelength and about one helical turn. Some species of Spirillum cause a form of RAT-BITE FEVER.
Growth of organisms using AUTOTROPHIC PROCESSES for obtaining nutrients and chemotrophic processes for obtaining a primary energy supply. Chemotrophic processes are involved in deriving a primary energy supply from exogenous chemical sources. Chemotrophic autotrophs (chemoautotrophs) generally use inorganic chemicals as energy sources and as such are called chemolithoautotrophs. Most chemoautotrophs live in hostile environments, such as deep sea vents. They are mostly BACTERIA and ARCHAEA, and are the primary producers for those ecosystems.
Vibrio- to spiral-shaped phototrophic bacteria found in stagnant water and mud exposed to light.
An enzyme that catalyzes the formation of 2 molecules of glutamate from glutamine plus alpha-ketoglutarate in the presence of NADPH. EC 1.4.1.13.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
A process facilitated by specialized bacteria involving the oxidation of ammonium to nitrite and nitrate.
Internal devices used in osteosynthesis to hold the position of the fracture in proper alignment. By applying the principles of biomedical engineering, the surgeon uses metal plates, nails, rods, etc., for the correction of skeletal defects.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
A genus of gram-negative bacteria in the family OXALOBACTERACEAE, comprised of vibrioid or sometimes helical cells. They are chemoorganotrophic nitrogen fixers and are found free-living in the soil or in association with the roots of members of the GRAMINEAE. (From Bergey's Manual of Determinative Bacteriology, 9th ed)
A family of compounds containing an oxo group with the general structure of 1,5-pentanedioic acid. (From Lehninger, Principles of Biochemistry, 1982, p442)
Plants whose roots, leaves, seeds, bark, or other constituent parts possess therapeutic, tonic, purgative, curative or other pharmacologic attributes, when administered to man or animals.
Genes which regulate or circumscribe the activity of other genes; specifically, genes which code for PROTEINS or RNAs which have GENE EXPRESSION REGULATION functions.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
Steel wires, often threaded through the skin, soft tissues, and bone, used to fix broken bones. Kirschner wires or apparatus also includes the application of traction to the healing bones through the wires.
A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)
Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.
Complex sets of enzymatic reactions connected to each other via their product and substrate metabolites.
A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.
Tungsten. A metallic element with the atomic symbol W, atomic number 74, and atomic weight 183.85. It is used in many manufacturing applications, including increasing the hardness, toughness, and tensile strength of steel; manufacture of filaments for incandescent light bulbs; and in contact points for automotive and electrical apparatus.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.
A phylum of bacteria consisting of the purple bacteria and their relatives which form a branch of the eubacterial tree. This group of predominantly gram-negative bacteria is classified based on homology of equivalent nucleotide sequences of 16S ribosomal RNA or by hybridization of ribosomal RNA or DNA with 16S and 23S ribosomal RNA.
Substances or mixtures that are added to the soil to supply nutrients or to make available nutrients already present in the soil, in order to increase plant growth and productivity.
A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)
Rods of bone, metal, or other material used for fixation of the fragments or ends of fractured bones.
A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)
Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.
The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)
The physiological restoration of bone tissue and function after a fracture. It includes BONY CALLUS formation and normal replacement of bone tissue.
The absence of light.
A large family of narrow-leaved herbaceous grasses of the order Cyperales, subclass Commelinidae, class Liliopsida (monocotyledons). Food grains (EDIBLE GRAIN) come from members of this family. RHINITIS, ALLERGIC, SEASONAL can be induced by POLLEN of many of the grasses.
A family of phototrophic bacteria, in the order Rhodospirillales, isolated from stagnant water and mud.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.
A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
An element that is a member of the chalcogen family. It has an atomic symbol S, atomic number 16, and atomic weight [32.059; 32.076]. It is found in the amino acids cysteine and methionine.
A low-molecular-weight (16,000) iron-free flavoprotein containing one molecule of flavin mononucleotide (FMN) and isolated from bacteria grown on an iron-deficient medium. It can replace ferredoxin in all the electron-transfer functions in which the latter is known to serve in bacterial cells.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
An enzyme that catalyzes the transfer of UMP from UDPglucose to galactose 1-phosphate, forming UDPgalactose and glucose 1-phosphate. Deficiency in this enzyme is the major cause of GALACTOSEMIA. EC 2.7.7.12.
One of the three domains of life (the others being BACTERIA and Eukarya), formerly called Archaebacteria under the taxon Bacteria, but now considered separate and distinct. They are characterized by: (1) the presence of characteristic tRNAs and ribosomal RNAs; (2) the absence of peptidoglycan cell walls; (3) the presence of ether-linked lipids built from branched-chain subunits; and (4) their occurrence in unusual habitats. While archaea resemble bacteria in morphology and genomic organization, they resemble eukarya in their method of genomic replication. The domain contains at least four kingdoms: CRENARCHAEOTA; EURYARCHAEOTA; NANOARCHAEOTA; and KORARCHAEOTA.
A family of organic anion transporters that specifically transport DICARBOXYLIC ACIDS such as alpha-ketoglutaric acid across cellular membranes.
A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria whose organisms arrange singly, in pairs, or short chains. This genus is commonly found in the intestinal tract and is an opportunistic pathogen that can give rise to bacteremia, pneumonia, urinary tract and several other types of human infection.
Processes by which phototrophic organisms use sunlight as their primary energy source. Contrasts with chemotrophic processes which do not depend on light and function in deriving energy from exogenous chemical sources. Photoautotrophy (or photolithotrophy) is the ability to use sunlight as energy to fix inorganic nutrients to be used for other organic requirements. Photoautotrophs include all GREEN PLANTS; GREEN ALGAE; CYANOBACTERIA; and green and PURPLE SULFUR BACTERIA. Photoheterotrophs or photoorganotrophs require a supply of organic nutrients for their organic requirements but use sunlight as their primary energy source; examples include certain PURPLE NONSULFUR BACTERIA. Depending on environmental conditions some organisms can switch between different nutritional modes (AUTOTROPHY; HETEROTROPHY; chemotrophy; or phototrophy) to utilize different sources to meet their nutrients and energy requirements.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Iron-containing proteins that transfer electrons, usually at a low potential, to flavoproteins; the iron is not present as in heme. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The republic consists of islands that are located in the mid-Atlantic Ocean about 300 miles off the west coast of Africa. The archipelago includes 10 islands and 5 islets, divided into the windward (Barlavento) and leeward (Sotavento) groups. The capital is Praia.
A DNA-directed RNA polymerase found in BACTERIA. It is a holoenzyme that consists of multiple subunits including sigma factor 54.
A fracture in which the bone is splintered or crushed. (Dorland, 27th ed)
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in archaea.
An enzyme found in bacteria. It catalyzes the reduction of FERREDOXIN and other substances in the presence of molecular hydrogen and is involved in the electron transport of bacterial photosynthesis.
A class in the phylum PROTEOBACTERIA comprised of chemoheterotrophs and chemoautotrophs which derive nutrients from decomposition of organic material.
Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.
An order of mostly marine CRUSTACEA containing more than 5500 species in over 100 families. Like ISOPODA, the other large order in the superorder Peracarida, members are shrimp-like in appearance, have sessile compound eyes, and no carapace. But unlike Isopoda, they possess thoracic gills and their bodies are laterally compressed.
Discrete segments of DNA which can excise and reintegrate to another site in the genome. Most are inactive, i.e., have not been found to exist outside the integrated state. DNA transposable elements include bacterial IS (insertion sequence) elements, Tn elements, the maize controlling elements Ac and Ds, Drosophila P, gypsy, and pogo elements, the human Tigger elements and the Tc and mariner elements which are found throughout the animal kingdom.
A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.
An abrupt voluntary shift in ocular fixation from one point to another, as occurs in reading.
A genus of gram-negative, rod-shaped, phototrophic bacteria found in aquatic environments. Internal photosynthetic membranes are present as lamellae underlying the cytoplasmic membrane.
DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.
Elements of limited time intervals, contributing to particular results or situations.
A large group of aerobic bacteria which show up as pink (negative) when treated by the gram-staining method. This is because the cell walls of gram-negative bacteria are low in peptidoglycan and thus have low affinity for violet stain and high affinity for the pink dye safranine.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
Proteins that contain an iron-porphyrin, or heme, prosthetic group resembling that of hemoglobin. (From Lehninger, Principles of Biochemistry, 1982, p480)
Salts and esters of hydroxybutyric acid.
A genus of GRAM-POSITIVE ENDOSPORE-FORMING RODS in the family Paenibacillaceae.
Voluntary or reflex-controlled movements of the eye.
A genus of anaerobic coccoid METHANOCOCCACEAE whose organisms are motile by means of polar tufts of flagella. These methanogens are found in salt marshes, marine and estuarine sediments, and the intestinal tract of animals.
Cultivated plants or agricultural produce such as grain, vegetables, or fruit. (From American Heritage Dictionary, 1982)
Structures within the nucleus of bacterial cells consisting of or containing DNA, which carry genetic information essential to the cell.
A highly reactive aldehyde gas formed by oxidation or incomplete combustion of hydrocarbons. In solution, it has a wide range of uses: in the manufacture of resins and textiles, as a disinfectant, and as a laboratory fixative or preservative. Formaldehyde solution (formalin) is considered a hazardous compound, and its vapor toxic. (From Reynolds, Martindale The Extra Pharmacopoeia, 30th ed, p717)
A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.
Deoxyribonucleic acid that makes up the genetic material of archaea.
Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.

Mutation in GDP-fucose synthesis genes of Sinorhizobium fredii alters Nod factors and significantly decreases competitiveness to nodulate soybeans. (1/1731)

We mutagenized Sinorhizobium fredii HH103-1 with Tn5-B20 and screened about 2,000 colonies for increased beta-galactosidase activity in the presence of the flavonoid naringenin. One mutant, designated SVQ287, produces lipochitooligosaccharide Nod factors (LCOs) that differ from those of the parental strain. The nonreducing N-acetylglucosamine residues of all of the LCOs of mutant SVQ287 lack fucose and 2-O-methylfucose substituents. In addition, SVQ287 synthesizes an LCO with an unusually long, C20:1 fatty acyl side chain. The transposon insertion of mutant SVQ287 lies within a 1.1-kb HindIII fragment. This and an adjacent 2.4-kb HindIII fragment were sequenced. The sequence contains the 3' end of noeK, nodZ, and noeL (the gene interrupted by Tn5-B20), and the 5' end of nolK, all in the same orientation. Although each of these genes has a similarly oriented counterpart on the symbiosis plasmid of the broad-host-range Rhizobium sp. strain NGR234, there are significant differences in the noeK/nodZ intergenic region. Based on amino acid sequence homology, noeL encodes GDP-D-mannose dehydratase, an enzyme involved in the synthesis of GDP-L-fucose, and nolK encodes a NAD-dependent nucleotide sugar epimerase/dehydrogenase. We show that expression of the noeL gene is under the control of NodD1 in S. fredii and is most probably mediated by the nod box that precedes nodZ. Transposon insertion into neoL has two impacts on symbiosis with Williams soybean: nodulation rate is reduced slightly and competitiveness for nodulation is decreased significantly. Mutant SVQ287 retains its ability to form nitrogen-fixing nodules on other legumes, but final nodule number is attenuated on Cajanus cajan.  (+info)

The nolL gene from Rhizobium etli determines nodulation efficiency by mediating the acetylation of the fucosyl residue in the nodulation factor. (2/1731)

The nodulation factors (Nod factors) of Rhizobium etli and R. loti carry a 4-O-acetyl-L-fucosyl group at the reducing end. It has been claimed, based on sequence analysis, that NolL from R. loti participates in the 4-O-acetylation of the fucosyl residue of the Nod factors, as an acetyl-transferase (D. B. Scott, C. A. Young, J. M. Collins-Emerson, E. A. Terzaghi, E. S. Rockman, P. A. Lewis, and C. E. Pankhurst. Mol. Plant-Microbe Interact. 9:187-197, 1996). Further support for this hypothesis was obtained by studying the production of Nod factors in an R. etli nolL::Km mutant. Chromatographic and mass spectrometry analysis of the Nod factors produced by this strain showed that they lack the acetyl-fucosyl substituent, having a fucosyl group instead. Acetyl-fucosylation was restored upon complementation with a wild-type nolL gene. These results indicate that the nolL gene determines 4-O-acetylation of the fucosyl residue in Nod factors. Analysis of the predicted NolL polypeptide suggests a transmembranal location and that it belongs to the family of integral membrane transacylases (J. M. Slauch, A. A. Lee, M. J. Mahan, and J. J. Mekalanos. J. Bacteriol. 178:5904-5909, 1996). NolL from R. loti was also proposed to function as a transporter; our results show that NolL does not determine a differential secretion of Nod factors from the cell. We also performed plant assays that indicate that acetylation of the fucose conditions efficient nodulation by R. etli of some Phaseolus vulgaris cultivars, as well as of an alternate host (Vigna umbellata).  (+info)

Microbiology of the oil fly, Helaeomyia petrolei. (3/1731)

Helaeomyia petrolei larvae isolated from the asphalt seeps of Rancho La Brea in Los Angeles, Calif., were examined for microbial gut contents. Standard counts on Luria-Bertani, MacConkey, and blood agar plates indicated ca. 2 x 10(5) heterotrophic bacteria per larva. The culturable bacteria represented 15 to 20% of the total population as determined by acridine orange staining. The gut itself contained large amounts of the oil, had no observable ceca, and maintained a slightly acidic pH of 6.3 to 6.5. Despite the ingestion of large amounts of potentially toxic asphalt by the larvae, their guts sustained the growth of 100 to 1,000 times more bacteria than did free oil. All of the bacteria isolated were nonsporeformers and gram negative. Fourteen isolates were chosen based on representative colony morphologies and were identified by using the Enterotube II and API 20E systems and fatty acid analysis. Of the 14 isolates, 9 were identified as Providencia rettgeri and 3 were likely Acinetobacter isolates. No evidence was found that the isolates grew on or derived nutrients from the asphalt itself or that they played an essential role in insect development. Regardless, any bacteria found in the oil fly larval gut are likely to exhibit pronounced solvent tolerance and may be a future source of industrially useful, solvent-tolerant enzymes.  (+info)

Superoxide dismutase and catalase in the protection of the proton-donating systems of nitrogen fixation in the blue-green alga Anabaena cylindrica. (4/1731)

1. Superoxide dismutase activity was present in the heterocysts and vegetative cells of Anabaena cylindrica, but was always lower in the heterocysts. 2. No qualitative differences were found in the superoxide dismutase from the two cellular types. 3. Catalase activity was also present in both cellular types. 4. Most of the NADP reductase activity, as assayed with menadione or ferredoxin as electron acceptor, was localized within the heterocysts. 5. Studies on H2 consumption showed that most of the hydrogenase activity was associated with the heterocysts. 6. The results are discussed in terms of the postulate that superoxide dismutase and catalase are involved in the protection of the proton-donating systems participating in N2 fixation and H2 metabolism of heterocysts.  (+info)

Rhizobium sp. strain NGR234 and R. fredii USDA257 share exceptionally broad, nested host ranges. (5/1731)

Genetically, Rhizobium sp. strain NGR234 and R. fredii USDA257 are closely related. Small differences in their nodulation genes result in NGR234 secreting larger amounts of more diverse lipo-oligosaccharidic Nod factors than USDA257. What effects these differences have on nodulation were analyzed by inoculating 452 species of legumes, representing all three subfamilies of the Leguminosae, as well as the nonlegume Parasponia andersonii, with both strains. The two bacteria nodulated P. andersonii, induced ineffective outgrowths on Delonix regia, and nodulated Chamaecrista fasciculata, a member of the only nodulating genus of the Caesalpinieae tested. Both strains nodulated a range of mimosoid legumes, especially the Australian species of Acacia, and the tribe Ingeae. Highest compatibilities were found with the papilionoid tribes Phaseoleae and Desmodieae. On Vigna spp. (Phaseoleae), both bacteria formed more effective symbioses than rhizobia of the "cowpea" (V. unguiculata) miscellany. USDA257 nodulated an exact subset (79 genera) of the NGR234 hosts (112 genera). If only one of the bacteria formed effective, nitrogen-fixing nodules it was usually NGR234. The only exceptions were with Apios americana, Glycine max, and G. soja. Few correlations can be drawn between Nod-factor substituents and the ability to nodulate specific legumes. Relationships between the ability to nodulate and the origin of the host were not apparent. As both P. andersonii and NGR234 originate from Indonesia/Malaysia/Papua New Guinea, and NGR234's preferred hosts (Desmodiinae/Phaseoleae) are largely Asian, we suggest that broad host range originated in Southeast Asia and spread outward.  (+info)

Differential regulation of two divergent Sinorhizobium meliloti genes for HPII-like catalases during free-living growth and protective role of both catalases during symbiosis. (6/1731)

Two catalases, KatA and KatB, have been detected in Sinorhizobium meliloti growing on rich medium. Here we characterize a new catalase gene encoding a third catalase (KatC). KatC activity was detectable only at the end of the stationary phase in S. meliloti growing in minimum medium, whereas KatA activity was found during the exponential phase. Analysis with a katC-lacZ fusion demonstrated that katC expression is mainly regulated at the transcription level. An increase of catalase activity correlating with KatA induction was detected in bacteroids. A dramatic decrease of nitrogen fixation capacity in a katA katC double mutant was observed, suggesting that these catalases are very important for the protection of the nitrogen fixation process.  (+info)

Azorhizobium caulinodans PII and GlnK proteins control nitrogen fixation and ammonia assimilation. (7/1731)

We herein report that Azorhizobium caulinodans PII and GlnK are not necessary for glutamine synthetase (GS) adenylylation whereas both proteins are required for complete GS deadenylylation. The disruption of both glnB and glnK resulted in a high level of GS adenylylation under the condition of nitrogen fixation, leading to ammonium excretion in the free-living state. PII and GlnK also controlled nif gene expression because NifA activated nifH transcription and nitrogenase activity was derepressed in glnB glnK double mutants, but not in wild-type bacteria, grown in the presence of ammonia.  (+info)

The fhu genes of Rhizobium leguminosarum, specifying siderophore uptake proteins: fhuDCB are adjacent to a pseudogene version of fhuA. (8/1731)

A mutant of Rhizobium leguminosarum was isolated which fails to take up the siderophore vicibactin. The mutation is in a homologue of fhuB, which in Escherichia coli specifies an inner-membrane protein of the ferric hydroxamate uptake system. In Rhizobium, fhuB is in an operon fhuDCB, which specifies the cytoplasmic membrane and periplasmic proteins involved in siderophore uptake. fhuDCB mutants make vicibactin when grown in Fe concentrations that inhibit its production in the wild-type. Nodules on peas induced by fhuDCB mutants were apparently normal in N2 fixation. Transcription of an fhuDCB-lacZ fusion was Fe-regulated, being approximately 10-fold higher in Fe-depleted cells. Downstream of fhuB, in the opposite orientation, is a version of fhuA whose homologues in other bacteria specify hydroxamate outer-membrane receptors. This fhuA gene appears to be a pseudogene with stop codons and undetectable expression.  (+info)

Introduction. Biological nitrogen fixation is a worldwide economical and sustainable alternative for nitrogen supply to legume crops. It may reduce the expenses with chemical nitrogen fertilizers, as well as eliminating the negative impact of them on the environment (Straliotto et al., 2002).. To take advantage of common bean (Phaseolus vulgaris L.) nitrogen biofertilizer, several studies have sought to identify efficient and competitive strains of rhizobia to cope the nitrogen requirements of this important crop. Unfortunately, biological nitrogen fixation in common bean field crops has exhibited unstable behavior (Mostasso et al., 2002; Hafeez et al., 2005; Soares et al., 2006).. Several approaches have been used to obtain new rhizobia strains which exhibit better biological nitrogen fixation responses on common bean. Typically, these strains are evaluated individually (Hungria et al., 2003; Soares et al., 2006) or in mixture with other strains (Hassan et al., 2004; Hafeez et al., 2005; ...
leaving the download Management of Biological Nitrogen Fixation for the Development of More Productive and Sustainable Agricultural Systems: Extended versions of papers presented at the Symposium on Biological Nitrogen of war has an Iranian research in Establishing the other pair of the Application. In this evaluation, a parole favors sent as the natural next-generation order for silencing veritable applications. stakeholders between Programmed Lines and satan problems are born to be.
The India-UK Nitrogen Fixation Centre (IUNFC) is a BBSRC-DBT joint-funded VJC aiming to tackle the problems of food security, the environmental and economic challenges of crop production and soil improvement in India through scientific research on nitrogen fixation. Formed in 2016, with lead investigators in India and the UK and a total of eight additional co-investigators from prestigious institutes and universities in both countries, IUNFC is carrying out world-class fundamental and applied research on biological nitrogen fixation (BNF) to increase scientific knowledge. In the short/medium term, this knowledge will lead to changes in agricultural practices in India, bringing economic, environmental and social benefits. In the longer term, it will provide a platform to engineer nitrogen fixation in cereal crops with implications for worldwide food security.. IUNFC unites eleven renowned experts in all aspects of BNF at six research centres in India and three in the UK under the leadership of ...
By Felix D. Dakora. This quantity covers contemporary advancements in either basic and utilized examine in organic nitrogen fixation. It emphasizes the applying of organic nitrogen fixation for sustainable agriculture, which should still result in poverty relief, environmental safeguard, and stable agricultural practices more often than not. the jobs of, and advances in, plant breeding, plant molecular biology, nodule body structure, and symbiotic and associative interactions among vegetation and microbes in maintaining agricultural productiveness and soil fertility are defined. The evolution of symbioses and nitrogen fixation also are coated during this quantity. to make sure excessive agricultural productiveness, whereas maintaining the surroundings (both soil and water resources), calls for plant cultivars that still reply to helpful microbes. the amount, for this reason, describes the body structure and genomics of nitrogen-fixing micro organism including the biochemistry and molecular ...
Field experiments at two sites, Elora and Arkell,were conducted to investigate the effect of plant water potential on the nitrogen fixation of two soybean cultivars, Vansoy and Anoka. The treatments were Vansoy and Anoka both under irrigated and non-irrigated conditions. The acetylene reduction technique was employed to estimate nitrogen fixation of nodules and measurements of plant water potential were made using the pressure chamber technique. Nitrogen fixation and plant water potential measurements were made at various stages during the entire growing period of the soybeans, and the results showed that water stress which was related to low plant water potential caused a reduction in nodule numbers, fresh weight and dry weight. There was evidence that moderate moisture stress mainly affected the amount of nodule tissue formed and not nitrogen fixing efficiency whereas severe stress led to reduction in both nodule mass and efficiency of fixation. The total seasonal amount of nitrogen fixed by ...
Stomatal closure is one of the first plant responses under a water deficit situation. This leads to a decline in transpiration but also in the plant photosynthetic activity. Legume plants grown under symbiosis with rhizobium bacteria present an inhibition of nitrogen fixation that has been shown to occur even before this of photosynthesis. One of the hypotheses to explain this rapid inhibition is the accumulation of nitrogen (N) compounds in nodules due to reduced transpiration, which would provoke the N-feedback inhibition of nitrogenase activity. The current work analyzes the effects of changes in transpiration rates in the regulation of nitrogen fixation through the application of the anti-transpirant Vapor Gard (VG) to pea (Pisum sativum L.) plants subjected to a progressive water deficit. VG produced a rapid inhibition of nitrogen fixation upon application. This inhibition, however, did not coincide with the accumulation of either amino acids or soluble carbohydrates observed at later ...
Abstract: To establish a nutrient solution system for soybean cultivation with effective nodulation and relatively high yield, we first evaluated the effect of nitrogen (N) content and rhizobia inoculation on soybean growth, yield and biological nitrogen fixation (BNF). Too high or too low N supply affected soybean growth, yield and N2 fixation capacity. Also, the required optimal N level was much higher for plant growth than that of BNF. Furthermore, the highest nitrogenase activity in soybean occurred before the first stage of reproduction (R1 stage). Thus, the enzyme activity could facilitate nodule formation and N2 fixation with a lower N supply before the R1 stage and a higher N supply afterward to promote plant growth and yield in soybean. A second experiment was conducted to optimize N supply (i.e., low N supply before R1 and medium N supply at the beginning of R1). As compared with continuously supplied high N, the optimal scheme promoted BNF with more and larger nodules with higher ...
TY - JOUR. T1 - Superradiance by molecular nitrogen ions in filaments. AU - Ivanov, N. G.. AU - Losev, V. F.. AU - Prokopev, V. E.. AU - Sitnik, K. A.. PY - 2016/7/1. Y1 - 2016/7/1. N2 - Results of the experimental study of population inversion in the resonant electronic transition В3Пg - А3 ∑+ u of nitrogen ions by optical pumping of atmospheric air and pure nitrogen by a femtosecond laser pulse at a wavelength of 950 nm are presented. It is shown that the inversion results from selective population of the N+ 2(B2 ∑+ u, V = 0) excited state during multiphoton excitation of the autoionization state of the nitrogen molecule with an energy of 18.7 eV. Seed photons for superradiance at transitions of molecular nitrogen ions are photons of the axial supercontinuum that occurs in a filament at the corresponding wavelengths. The superradiance mode is implemented at the wavelength λ = 358.4 nm referred to the transition of the CN molecule.. AB - Results of the experimental study of population ...
Abstract. The balance between denitrification and nitrogen fixation is the key control of the availability of nitrogen in coastal ecosystems and thus the primary productivity of these environments. However, evaluating the importance of denitrification and nitrogen fixation over large spatial and temporal scales is problematic. In this study, a combined mass and stable isotope balance of nitrogen was used to constrain the cycling of nitrogen in Western Port, Victoria - a temperate, intertidal embayment in south-eastern Australia. This method is a more effective approach compared to the extrapolation of discrete measurements and geochemical approaches. The validity of the isotope and mass balance model has been tested by comparing the output of the model with the average measured isotopic signature of the sediment in Western Port. Using previously measured rates of nitrogen fixation and denitrification in combination with the isotopic signature of nitrogen inputs from the catchment, atmosphere and ...
Biological nitrogen fixation (BNF) by plants and its bacterial associations represent an important natural system for capturing atmospheric dinitrogen (N2) and processing it into a reactive form of nitrogen through enzymatic reduction. The study of BNF in non-leguminous plants has been difficult compared to nodule-localized BNF in leguminous plants because of the diverse sites of N2 fixation in non-leguminous plants. Identification of the involved N2-fixing bacteria has also been difficult because the major nitrogen fixers were often lost during isolation attempts. The past 20 years of molecular analyses has led to the identification of N2 fixation sites and active nitrogen fixers in tissues and the rhizosphere of non-leguminous plants. Here, we examined BNF hotspots in six reported non-leguminous plants. Novel rhizobia and methanotrophs were found to be abundantly present in the free-living state at sites where carbon and energy sources were predominantly available. In the carbon-rich apoplasts of
Nitrogen Fixation Nitrogen fixation refers to the conversion of atmospheric nitrogen gas (N2) into a form usable by plants and other organisms. Nitrogen fixation is conducted by a variety of bacteria, both as free-living organisms and in symbiotic association with plants.
Anés group will work with Sushmita Roy, a professor of biostatistics and medical informatics at the Wisconsin Institute for Discovery, to lead this evolutionary investigation. The UW-Madison researchers will then partner with colleagues at the University of Florida to begin testing groups of genes that could confer nodulation and bacterial symbiosis - and ultimately nitrogen fixation - on poplar.. Ané says that this project continues a long tradition of studying nitrogen fixation at UW-Madison.. UW-Madison for decades has been a leader in research on nitrogen fixation, in biochemistry, in agronomy, and in bacteriology. There has been a really long history of research on the enzyme that performs nitrogen fixation, he says.. While the new grant aims to develop nitrogen fixation in poplar, food crops are also a target. Ané says that the Wisconsin Crop Innovation Center, a plant biotechnology center at UW-Madison, provides the expertise that would be required to translate findings from poplar ...
Several wild-type strains of Rhizobium meliloti isolated from alfalfa nodules exhibited different plasmid profiles, yet did not differ in growth rate in yeast-mannitol medium, utilization of 43 different carbon sources, intrinsic resistance to 14 antibiotics, or detection of 16 enzyme activities. In contrast, three measures of effectiveness in symbiotic nitrogen fixation with alfalfa (shoot length, dry weight, and nitrogen content) indicated that R. meliloti SAF22, whose plasmid profile differs from those of the other strains tested, is significantly less effective than other wild-type strains in symbiotic nitrogen fixation. Light microscopy of nodules infected with strain SAF22 showed an abnormal center of nitrogen fixation zone III, with bacteria occupying a smaller portion of the infected host cells and vacuoles occupying a significantly larger portion of adjacent uninfected host cells. In contrast, the effective nodules infected with other wild types or plasmid pRmSAF22c-cured segregants of ...
Mineral nturient defiencies are a major constraint limiting legume nitrogen fixation and yield. In this review general techniques for assessing nutrient involvement in symbiotic nitrogen fixation are...
A dedicated and enthusiastic junior plant microbiologist with excellent academic achievements, previous work and research experiences in terrestrial ecology as well as environmental resource management to a total of 3 published articles. Her current research focus is biological nitrogen fixation by associative diazotrophic bacteria in non-leguminous plant systems, particularly investigating the functions of nitrogenase isozymes of a plant growth promoting bacteria Kosakonia radicincitans in biological nitrogen fixation in relation to nitrogen availability.. ...
Biological dinitrogen fixation by Rhizobium spp. in the root nodules of leguminous plants such as soybean is of considerable agronomic importance. Biological dinitrogen fixation is ATP- and reductant-dependent; between 12 and 30 mol of ATP are required per mol of dinitrogen reduced [1]. All free-living rhizobia are aerobic although some strains will also grow anaerobically with nitrate as the terminal electron acceptor [2] ; ATP and reductant are generated during the oxidation of an exogenously supplied carbon source. In the bacteroids within the root nodule the exogenous carbon source (photosynthate) is derived from photosynthetic CO₂ fixation by the host plant. The identity of the carbon source(s) oxidised by the bacteroids in vivo has not yet been confirmed although sucrose is the major photosynthetic product translocated to the root nodules [3]. As dinitrogen fixation represents a drain on the photosynthetic supply [4,5] and since the supply of photosynthate is probably one of the major ...
Fixation of nitrogen even with liberation of energy or free energy, will take place if either oxygen gas or hydrogen gas, or other substances, especially gases, whose standard free energies are close to zero, are involved to form either nitrates, ammonia, or cyanide, not to speak of still other compounds. It has been pointed out that there are two and only two general conditions where nitrogen fixation can require energy. These are, first, if nitrogen reacts with some compound like water with an already high negative free energy of formation and where negligible oxidation of nitrogen would occur; second, if the plant does not take advantage of working at concentrations where the process would yield free energy.. If nitrogen fixation is exothermic and free energy-yielding, how is the carbohydrate requirement of nitrogen-fixing organisms to be interpreted? Are the experimental determinations of the carbon to nitrogen ratio purely circumstantial? Is further hope given to those who may ...
Human activities affect the impact of the nitrogen cycle on both the environment and climate. The rate of anthropogenic nitrogen fixation from atmospheric N2 may serve as an indicator to the magnitude of this impact, acknowledging that relationship to be effect-dependent and non-linear. Building on the set of Representative Concentration Pathway (RCP) scenarios developed for climate change research, we estimate anthropogenic industrial nitrogen fixation throughout the 21st century. Assigning characteristic key drivers to the four underlying scenarios we arrive at nitrogen fixation rates for agricultural use of 80 to 172 Tg N/yr by 2100, which is slightly less to almost twice as much compared with the fixation rate for the year 2000. We use the following key drivers of change, varying between scenarios: population growth, consumption of animal protein, agricultural efficiency improvement and additional biofuel production. Further anthropogenic nitrogen fixation for production of materials such as ...
TY - ABST. T1 - ¤In vivo¤ studies of nitrogen fixation and assimilation in pea-¤Rhizobium¤ nodules by 15N NMR spectroscopy. AU - Scharff, A.M.. AU - Hansen, P.E.. AU - Rosendahl, L.. N1 - Conference code: 3. PY - 1998. Y1 - 1998. KW - Planteproduktion og stofomsætning. M3 - Conference abstract for conference. T2 - 3rd European Nitrogen Fixation Conference. Y2 - 20 September 1998 through 24 September 1998. ER - ...
Beijerinck, M. W. Über oligonitrophile Mikroben. Zbl. Backt. 7, 561-582 (1901). Benson, D. R. & Silvester, W. B. Biology of Frankia strains, actinomycete symbionts of actinorhizal plants. Microbiological Reviews 57, 293-319 (1993).
Nitrogen Fixation Definition - Nitrogen fixation is a chemical process that converts atmospheric nitrogen into ammonia, which is absorbed by organisms...
Definition of NITROGEN FIXATION: Natural process that takes free nitrogen (N2) from the air, converts or fixes it in nitrogen compounds that plants use as nutrients, as in fertilizer. In
Subscribe: Apple Podcasts , Google Podcasts , RSS. Paul, Jocelyn and Fred continue their discussion with Pauls announcement of Ant village 2017 pricing. They then move on to more listener questions. The first one pertains to what ratio of nitrogen fixers Paul recommends for planting. They talk about the issue of chopped and dropped branches breaking down in a dry climate and they […]. ...
Beginning Easy to perform; requires no experience in microbiology. For 30 students. Members of the genus Rhizobium exist in a symbiotic relationship with leguminous plants (peas, clover, and soybeans). The Rhizobium growing in nodules on the roots of leguminous plants fix atmospheric nitrogen (...
Symbiotic Nitrogen Fixation. Our girls cannot survive without nitrogen. We all know that. Unfortunately, they cant just breath nitrogen gas which is abundant in air. Instead, microbiological organisms use the ammonia form of nitrogen to manufacture the proteins and other nitrogen-containing nutrients needed to survive. So, what plants can we use to get this task done? Its our cover crop plants. Peas, beans and other legumes fix atmospheric nitrogen using small growths on their roots called nodules. Those microbes, and the bacteria in your Recharge, then act as the plant nitrogen broker. Your girls ask the microbes for N, the microbes go get it from the nodules and bring it back for the plant in exchange for some sugar love. Through this symbiotic practice of nitrogen fixation, you will spend less on nitrogen fertilizer.. Mutual Climate Co-operation. Mutual climate co-operation refers to planting crops that, when they become full size, complement the needs of plants growing around them. A good ...
Automatic Addition Control of the External Carbon Source by the Measurement of ORP in Biological Nitrogen Removal Process - Biological nitrogen removal;External carbon source;COD/N ratio;Oxidation-reduction potential;PID control;
Although it seems likely that iron availability is influential in determining where in the oceans that nitrogen-fixers can live, it is less clear that the rate of iron supply to the ocean controls the amount of nitrogen-fixation taking place. In-situ measurements suggest that N2-fixation is co-limited by both phosphate and iron in one of the areas where N2-fixation is most intense. There are also other areas where phosphate is relatively abundant but iron scarce, and in which nitrogen-fixers do not thrive. It is likely that a temporary increase in the amount of dust falling into the ocean surface would open up new areas to nitrogen-fixers (which iron scarcity has previously prevented them colonising) and lead to a temporary increase in global nitrogen-fixation. However, such an increase could most likely not be sustained indefinitely. Eventually the increased phosphate use would impoverish ocean stocks of phosphate, and global nitrogen-fixation would become increasingly controlled by phosphate ...
Although it seems likely that iron availability is influential in determining where in the oceans that nitrogen-fixers can live, it is less clear that the rate of iron supply to the ocean controls the amount of nitrogen-fixation taking place. In-situ measurements suggest that N2-fixation is co-limited by both phosphate and iron in one of the areas where N2-fixation is most intense. There are also other areas where phosphate is relatively abundant but iron scarce, and in which nitrogen-fixers do not thrive. It is likely that a temporary increase in the amount of dust falling into the ocean surface would open up new areas to nitrogen-fixers (which iron scarcity has previously prevented them colonising) and lead to a temporary increase in global nitrogen-fixation. However, such an increase could most likely not be sustained indefinitely. Eventually the increased phosphate use would impoverish ocean stocks of phosphate, and global nitrogen-fixation would become increasingly controlled by phosphate ...
Uniquely identifiable characteristics Distinguishing Feature : The black and white markings on the wings (petals), with the black being very rare amongst wild plants. One of the very few wild flowers with black flowers (or at least black patches with purple splodges, on a white base). Like all members of the pea family, the Broad Bean plant has the ability to fix nitrogen directly from the air in the soil, a remarkable feat most other plants outside the Pea Family lack. The biological nitrogen fixation is accomplished by symbiotic bacteria living in the nodules on the roots. These bacteria are sensitive to oxygen, requiring the absence of it. Plants in the Pea Family are therefore thus almost self-fertilising, not requiring additional nitrogen fertilisers. The majority of plants that are not in the Pea Family that have nitrogen fixing bacteria are trees or shrubs, of which Sea-Buckthorn is one. Plants with nitrogen-fixing root nodules are called Actinorhizal. Broad Bean also has the ability to ...
levels and temperature rise globally, scientists increasingly want to know which organisms will thrive and which will perish in the environment of tomorrow.. The answer to this question for nitrogen-fixing cyanobacteria (bacteria that obtain energy through photosynthesis, or blue-green algae) turns out to have implications for every living thing in the ocean. Nitrogen-fixing is when certain special organisms like cyanobacteria convert inert - and therefore unusable - nitrogen gas from the air into a reactive form that the majority of other living beings need to survive. Without nitrogen fixers, life in the ocean could not survive for long.. Our findings show that CO2 has the potential to control the biodiversity of these keystone organisms in ocean biology, and our fossil fuel emissions are probably responsible for changing the types of nitrogen fixers that are growing in the ocean, said David Hutchins, professor of marine environmental biology at the USC Dornsife College of Letters, Arts ...
Attention for Chapter 13: Biochemistry and physiology of nitrogen fixation with particular emphasis on nitrogen-fixing phototrophs ...
The endosymbiotic relationship between nitrogen-fixing rhizobial bacteria and certain plants (legumes) is of the utmost importance for the nitrogen cycle in the biosphere and hence an object of intense study by specialists from various areas of biology. What is more, although the use of artificial nitrogen-containing fertilizers made it possible to bypass the strict dependence on this process, its understanding is still crucial for the efficient agriculture. Biological nitrogen fixation requires nitrogenase, an enzyme present in, among others, rhizobial bacteria but absent in plants. The rhizobia are a diverse range of soil bacteria. It is thought that after the symbiotic capabilities were first acquired by some of them, they spread by means of horizontal transfer of a plasmid or genomic island containing genes important for the process. The symbiotic relationship between the two symbionts depends on the formation of invasion structures (nodules) by the host, allowing bacteria to enter the plant ...
The ability of bacteria to respond to a multitude of environmental signals and integrate these signals to trigger adaptive responses provides a successful strategy for survival in rapidly changing environments. In many cases integration can be achieved via the interlinking of different regulatory circuits in which various master regulators respond to different environmental cues. However, in some systems an economy of scale can be achieved if individual regulatory proteins are able to respond to more than one input signal. In this review we consider a particular example where multiple signals are integrated by a regulatory protein complex to finely tune transcriptional regulation of nitrogen fixation in free-living diazotrophic bacteria.. The ability to fix atmospheric nitrogen to ammonia by using the enzyme nitrogenase enables diazotrophs not only to survive but also to proliferate under conditions of extreme fixed-nitrogen deprivation. This strategy, however, incurs an energetic penalty since ...
The most important role of the molybdenum in living organisms is as a metal heteroatom at the active site in certain enzymes In nitrogen fixation in certain bacteria Get Price ...
View Notes - reviewsheet from BI 112 at N. Michigan. Terms for Exam 2 nitrogen fixation restriction endonuclease endotoxin exotoxin lipopolysaccharide super antigen endosymbiosis algae protozoan
Find nitrogen fixation books and publications on agriculture-xprt.com, the worlds largest agricultural industry marketplace and information resource.
FP4,,03010204,UNIVERSITY OF MANCHESTER INSTITUTE OF SCIENCE AND TECHNOLOGY(UK),LEIDEN UNIVERSITY(NL),Beijing Agricultural University(CN),Huazhong Agricultural University(CN),UNIVERSIDAD DE SEVILLA(ES),Rijksuniversiteit Utrecht(NL)
Metagenomics sequencing was used to reveal the diversity of genes and their metabolic pathways involved in carbon sequestration and nitrogen fixation in moss crusts in Shapotou region, located southeast of the Tengger Desert. Results showed that the microbial community related to the bacteria domain in the moss crust was the largest, followed by archaea and eukaryota. In the bacterial domain, the most abundant phyla was the Actinobacteria, followed by the Proteobacteria and Cyanobacteria. Based on the functional classification of eggNOG and KEGG databases for the functional prediction of non-redundant gene catalog, the diversity of gene and metabolic pathways in the moss crust soil was high. Low nitrogen fixation was found in the moss crust as there are less metabolic pathways related to nitrogen-fixation, weakening the ecological function of ammonia synthesis from atmosphere nitrogen. The nitrate from the nitrogen pool formed by moss crust were mainly reduced to ammonium salt by nitrate ...
Some might say that rhizobium bacteria may well continue to fix nitrogen in plant roots even when the tops of peas, beans and tares have been cut off. I would question this because nitrogen fixation is a very energy intensive process. The energy to promote nitrogen fixation in the root nodule of legumes comes from the plant. While there may be a small amount of stored food in the roots this will quickly be used up by the nitrogen fixing process. Once the energy from the food is used up, nitrogen fixation will cease because there are no photosynthesizing structures to replenish the food. Any nitrogen that is fixed will pass straight into the root and will only be released when the roots decompose ...
Stock video footage Rhizobium nitrogen-fixing bacteria. Coloured scanning electron micrograph (SEM) of nitrogen-fixing soil bacteria (Rhizobium sp.). These bacteria are often found living ...
Shop a large selection of Proteins A-Z products and learn more about Novus Biologicals N4BP2L2 Recombinant Protein Antigen Quantity: 100µg:Life Quantity: 100µg.
Interpretive Summary: Technical Abstract: A lush field consisting of a mixture of grass and legumes is the goal of many producers. Such a production system has many benefits. The most important in times of high fertilizer prices is the reduced need for nitrogen (N) because of the legumes capacity for biological nitrogen fixation. However, attaining a productive grass-legume mixture can be frustrating, and stands with the desired mixture are often short-lived. Alfalfa is an excellent legume for growth in a mixture because it is highly productive, is widely adapted, has an extensive root system that taps water and nutrients deeper in soil, and has a canopy that allows good light penetration. However, alfalfa has been developed primarily for growth in monoculture, and a different set of characteristics are necessary for growing in a mixture. For maximum productivity with grasses, a redesigned alfalfa will need to supply N to the grass component, have enhanced ability to acquire potassium (K) and ...
The intensification of western boundary currents in the global ocean will potentially influence meso-scale eddy generation, and redistribute microbes and their associated ecological and biogeochemical functions. To understand eddy-induced changes in microbial community composition as well as how they control growth, we targeted the East Australian Current (EAC) region to sample microbes in a cyclonic (cold-core) eddy (CCE) and the adjacent EAC. Phototrophic and diazotrophic microbes were more diverse (2-10 times greater Shannon index) in the CCE relative to the EAC, and the cell size distribution in the CCE was dominated (67%) by larger micro-plankton [Formula: see text], as opposed to pico- and nano-sized cells in the EAC. Nutrient addition experiments determined that nitrogen was the principal nutrient limiting growth in the EAC, while iron was a secondary limiting nutrient in the CCE. Among the diazotrophic community, heterotrophic NifH gene sequences dominated in the EAC and were ...
During photosynthesis, photosystem II generates oxygen by splitting water molecules. Because oxygen inhibits nitrogen fixation, most nitrogen-fixing cyanobacteria only fix nitrogen at night, or do it in specialized cells. The lack of photosystem II enables the new microbe to fix nitrogen during the day, Zehr said. But without photosynthesis, it cant take carbon dioxide from the atmosphere and convert it into sugars. So its not clear how the new microbe feeds itself. Either it has some way of feeding on organic matter in its environment, or it lives in close association with other organisms that provide it with food, Zehr said.. It would make a perfect symbiont because it could feed nitrogen to its host and live on the carbon provided by the host, he said. Zehrs team was able to obtain a mostly pure sample of these unique cyanobacteria using a flow cytometer--a device that rapidly sorts individual cells based on size and color. The flow cytometer can take the cell soup from an ocean sample, ...
Rhizobium meliloti elicits the development of specialized organs on the plant roots called nodules. How nitrogen fixation genes are coordinately expressed specifically within the nodule is an important question in understanding the plant-microbe symbiosis. Homologs of nif genes have been identified in R. meliloti, but inactivation of these genes by transposon mutagenesis does not affect symbiosis. The fact that FixL* retains oxygen-regulated activity in vitro demonstrates that the amino-terminal membrane attachment domain is not essential for FixL function. The net effect, then, is an increase in the level of phospho-FixJ. The development of an oxygen-regulated in vitro transcription system is an important step in the study of FixJ action at target promoters. Two-component response regulators that function as transcription factors can be divided into three subclasses based on sequence similarity outside the universally conserved N-terminal phosphoryl acceptor domain. In contrast with many other systems,
I find only a few minor contentious issues in Professor Moran´s post, so I prefer not to bother the readers with details about them. In my opinion, it is important that we have started to look at the core issue - the average fixation of about 100 mutations per generation, or 22,000,000 in 5,000,000 years, according to the genetic drift model - in terms of close to real-life conditions. Now we see that the simple genetic drift model needs extension, to include population splitting and recombining that leads to the postponement of fixation (I thank Professor Felsenstein for improving the clarity of this point). Furthermore, we see that in expanding populations the fixation rate is lower than the average. Thus, in today´s human population, the fixation rate per generation is close to zero. In order to compensate for the lower than the average fixation rates in some generations, it is necessary to postulate higher than the average fixation rates in other generations, if one wishes to account for ...
I find only a few minor contentious issues in Professor Moran´s post, so I prefer not to bother the readers with details about them. In my opinion, it is important that we have started to look at the core issue - the average fixation of about 100 mutations per generation, or 22,000,000 in 5,000,000 years, according to the genetic drift model - in terms of close to real-life conditions. Now we see that the simple genetic drift model needs extension, to include population splitting and recombining that leads to the postponement of fixation (I thank Professor Felsenstein for improving the clarity of this point). Furthermore, we see that in expanding populations the fixation rate is lower than the average. Thus, in today´s human population, the fixation rate per generation is close to zero. In order to compensate for the lower than the average fixation rates in some generations, it is necessary to postulate higher than the average fixation rates in other generations, if one wishes to account for ...
ST. JOSPEH, Mo. - Farmers fixation on nitrogen fixation is two fold: yield and cost. Pulse crop margins are built on reasonable prices for the commodities
Jones, K.M.; Haselkorn, R., 2002: Newly identified cytochrome c oxidase operon in the nitrogen-fixing cyanobacterium Anabaena sp. strain PCC 7120 specifically induced in heterocysts
New methodologies and approaches in stable isotope analysis; Measurement of biological nitrogen fixation using 15N additions; The 15N natural abundance method for measurement of biological nitrogen fixation; Applications of 15N methods to measurement of biological nitrogen fixation; Stable isotopes in soil organic matter studies; Soil nitrogen transformations and losses; Nutrient uptake and use by the plant; Stable isotopes in studies of plant metabolism; 13C / 12C discrimination as a measure of water use efficiency; 13C in studies of plant carbon balance; Stable isotopes in water transport studies; Sulphur flows and transformations in ecosystems; Atmospheric change and aerial pollutants.
A nitrogen-fixing bacterium, designated strain 6H33bT, was isolated from a compost pile in Japan. The nitrogenase activity of this strain was detected based on its acetylene-reducing activity under low oxygen concentrations (2-4 %). An analysis of the genes responsible for nitrogen fixation in this strain, nifH and nifD, indicated a close relationship to those of Pseudomonas stutzeri A15 (A1501). Sequence similarity searches based on the 16S rRNA gene sequences showed that strain 6H33bT belongs within the genus Pseudomonas sensu stricto; closest similarity was with Pseudomonas indica (97·3 %). A comparison of several taxonomic characteristics of 6H33bT with those of P. indica and some type strains of the genus Pseudomonas sensu stricto indicated that 6H33bT could be distinguished from P. indica based on the presence of nitrogen fixation ability, the absence of nitrate reduction and denitrification abilities and the utilization of some sugars and organic acids. Phylogenetic analyses and the results of
Given that nitrogen (N) is a limiting nutrient in boreal ecosystems, biological N fixation can have a large influence on primary production and other processes in this ecosystem. To date, most studies focused on N fixation in boreal ecosystems have focused on bryophyte-cyanobacteria associations, whereas relatively few studies have investigated the significance of N fixation by lichens. In this study I examined how biomass and aerial N fixation rates of two common terricolous lichens, Nephroma arcticum (L.) Torss. and Peltigera aphthosa (L.) Willd., varied across a boreal chronosequence, where time since fire varied from 43 to 362 years. The main objective of the study was to observe how stand age influenced biomass and N fixation rates of terricolous lichens, which has been extensively described in previous studies for bryophyte-cyanobacteria associations. The study revealed that biomass and consequently N fixation rate per unit area for both lichen species significantly increased with time ...
TY - JOUR. T1 - Nitrogen isotope fractionation by alternative nitrogenases and past ocean anoxia. AU - Zhang, Xinning. AU - Sigman, Daniel Mikhail. AU - Morel, Francois M. M.. AU - Kraepiel, Anne M.L.. PY - 2014/4/1. Y1 - 2014/4/1. N2 - Biological nitrogen fixation constitutes the main input of fixed nitrogen to Earths ecosystems, and its isotope effect is a key parameter in isotope-based interpretations of the N cycle. The nitrogen isotopic composition (δ15N) of newly fixed N is currently believed to be∼-10/00, based on measurements of organic matter from diazotrophs using molybdenum (Mo)-nitrogenases. We show that the vanadium (V)- and iron (Fe)-only alternative nitrogenases produce fixed N with significantly lower δ15N (-6 to -70/00). An important contribution of alternative nitrogenases to N2 fixation provides a simple explanation for the anomalously low δ15N (,-20/00) in sediments from the Cretaceous Oceanic Anoxic Events and the Archean Eon. A significant role for the alternative ...
SUMMARY: 55FeCI3 labelling and non-denaturing gel electrophoresis were used to study nitrogenase synthesis in Gloeothece sp. CCAP 1430/3. Nitrogenase synthesis was inhibited by addition of NHX but was unaffected by elevated concentrations of O2. Upon transfer of cultures of Gloeothece from light to darkness, there was initially a slight decrease in the rate of synthesis of nitrogenase but after 4-5 h there was an almost complete cessation of synthesis. This delayed effect of darkness on nitrogenase synthesis could not be related to any change in RNA synthesis, in protein synthesis or in the rate of breakdown of storage glucan. In cultures of Gloeothece, mRNA, including nif mRNA, was unstable, having a half-life of about 5 min. The synthesis of nif mRNA did not stop immediately upon transfer of cultures to the dark. If darkness exerts its effect on nitrogenase synthesis by inhibiting the synthesis of nif mRNA, it does so only after a lag of about 4 h.
Cyanothece sp. PCC 7822 is an excellent cyanobacterial model organism with great potential to be applied as a biocatalyst for the production of high value compounds. Like other unicellular diazotrophic cyanobacterial species, it has a tightly regulated metabolism synchronized to the light-dark cycle. Utilizing transcriptomic and proteomic methods, we quantified the relationships between transcription and translation underlying central and secondary metabolism in response to nitrogen free, 12 hour light and 12 hour dark conditions. By combining mass-spectrometry based proteomics and RNA-sequencing transcriptomics, we quantitatively measured a total of 6766 mRNAs and 1322 proteins at four time points across a 24 hour light-dark cycle. Photosynthesis, nitrogen fixation, and carbon storage relevant genes were expressed during the preceding light or dark period, concurrent with measured nitrogenase activity in the late light period. We describe many instances of disparity in peak mRNA and protein abundances,
Cyanothece sp. PCC 7822 is an excellent cyanobacterial model organism with great potential to be applied as a biocatalyst for the production of high value compounds. Like other unicellular diazotrophic cyanobacterial species, it has a tightly regulated metabolism synchronized to the light-dark cycle. Utilizing transcriptomic and proteomic methods, we quantified the relationships between transcription and translation underlying central and secondary metabolism in response to nitrogen free, 12 hour light and 12 hour dark conditions. By combining mass-spectrometry based proteomics and RNA-sequencing transcriptomics, we quantitatively measured a total of 6766 mRNAs and 1322 proteins at four time points across a 24 hour light-dark cycle. Photosynthesis, nitrogen fixation, and carbon storage relevant genes were expressed during the preceding light or dark period, concurrent with measured nitrogenase activity in the late light period. We describe many instances of disparity in peak mRNA and protein abundances,
Pulses benefit crop rotations by diversifying cropping options, reducing problems associated with monoculture, and they add some nitrogen to the succeeding crop. Nitrogen in the past two years has become an increasingly expensive crop input, so reducing reliance on fertilizer by increasing the nitrogen fixation contribution is a sustainable solution. Legumes like pea, bean, chickpea, lentil and faba can make their own nitrogen by nitrogen fixation, a process which occurs in special nodules formed on the roots by a symbiotic relationship with rhizobia bacteria and the host plant. Recently low tannin faba have been bred at the Crop Development Center, University of Saskatchewan, making faba an attractive crop for food and feed. Faba is a larger crop in terms of height, stem thickness and biomass than pea, and it is a cool season crop that is also fairly tolerant of temperature and drought stress. Faba is superior to pea in stressful years with drought and heat. The standing biomass of stubble and ...
Maize (Zea mays L.) is a major staple food in Sub-Saharan Africa but low soil fertility, limited resources and droughts keep yields low. Cultivation of maize intercropped with pigeonpea (Cajanus cajan L. Millsp.) is common in some areas of eastern and southern Africa. The objectives of this study were (1) to investigate dry matter, nitrogen (N) and phosphorus (P) accumulation in different plant components of maize-pigeonpea intercropping systems and (2) to report the effects of the intercrops on soil fertility. Maize-pigeonpea intercrops were compared to sole maize grown using farmers practices. Intercropping maize and pigeonpea increased (P,0.05) total system yield compared to sole maize in terms of biomass, N and P accumulation. Pigeonpea planted in maize did not reduce (P,0.05) the accumulation of dry matter, N nor P in the maize grain. The harvest indices of maize, calculated on basis dry matter, N or P did not differ either (P,0.05). Total soil C and N contents and inorganic N content, ...
Biological nitrogen fixation (BNF) in legumes plays a critical role in improving soil fertility. Despite this vital role, there is limited information on the genetic diversity and BNF of bacteria nodulating common bean (Phaseolus vulgaris L.). This study evaluated the genetic diversity and symbiotic nitrogen fixation of bacteria nodulating common bean in soils of Western Kenya. The genetic diversity was determined using 16S rRNA gene partial sequences while BNF was estimated in a greenhouse experiment. The sequences of the native isolates were closely affiliated with members from the genera Pantoea, Klebsiella, Rhizobium, Enterobacter and Bacillus. These results show that apart from rhizobia, there are non-rhizobial strains in the nodules of common bean. The symbiotic efficiency (SE) of native isolates varied and exhibited comparable or superior BNF compared to the local commercial inoculants (CIAT 899 and Strain 446). Isolates (MMUST 003 [KP027691], MMUST 004 [KP027687], MMUST 005 [KP027688], ...
Seventeen genes specifically required for nitrogen fixation are clustered on the chromosome of Klebsiella pneumoniae and form a complex regulon that is organized into eight transcriptional units. The nif promoters are representative of a new class of promoter, the members of which lack the consensus sequences normally found in prokaryotic promoters, nif gene transcription is positively controlled and requires: (1) the ntrA gene product, which replaces the rpoD-encoded sigma subunit of RNA polymerase to allow recognition of nif promoter sequences; and (2) the product of either the nitrogen regulation gene ntrC or the specific nif regulatory gene, nifA, which are both transcriptional activators. Most nif promoters require an upstream activator sequence (UAS) for nifA-mediated activation. The UAS acts independently of orientation and can function when placed 2 kilobases upstream from the transcription start site. Current evidence suggests that activation requires an interaction between proteins ...
TY - JOUR. T1 - Onset of the aerobic nitrogen cycle during the Great Oxidation Event. AU - Zerkle,Aubrey L.. AU - Poulton,Simon W.. AU - Newton,Robert J.. AU - Mettam,Colin. AU - Claire,Mark W.. AU - Bekker,Andrey. AU - Junium,Christopher K.. PY - 2017/2/23. Y1 - 2017/2/23. N2 - The rise of oxygen on the early Earth (about 2.4 billion years ago) caused a reorganization of marine nutrient cycles, including that of nitrogen, which is important for controlling global primary productivity. However, current geochemical records lack the temporal resolution to address the nature and timing of the biogeochemical response to oxygenation directly. Here we couple records of ocean redox chemistry with nitrogen isotope (15N/14N) values from approximately 2.31-billion-year-old shales of the Rooihoogte and Timeball Hill formations in South Africa, deposited during the early stages of the first rise in atmospheric oxygen on the Earth (the Great Oxidation Event). Our data fill a gap of about 400 million years in ...
China X-ray Film Fixer /Automatic, Find details about China Automatic Fixer, X-ray Fixer from X-ray Film Fixer /Automatic - Shenzhen Fumingwei Industrial Company Limited
General Information: Gluconacetobacter diazotrophicus strain PAL5 (ATCC 49037) was isolated from sugarcane roots in Brazil. Nitrogen-fixing plant symbiont. This acid-tolerant organism is endophytic and colonizes internal plant tissues, establishing a symbiotic relationship with its host. This bacterium has been found in sugarcane, coffee, rice, tea, and other plants. The nitrogen-fixation systems of the bacterium provide the plant with essential nitrogenous compounds while the plant provides a protected environment for the bacterium to grow in. Nitrogen-fixation is important for sugarcane production, and this organism can fix nitrogen even in the presence of nitrate. ...
The nitrogenase enzyme, which catalyzes the reduction of N2 gas to NH4+, occurs as three separate isozyme that use Mo, Fe-only, or V. The majority of global nitrogen fixation is attributed to the more efficient canonical Mo-nitrogenase, whereas Fe-only and V-(alternative) nitrogenases are often considered backup enzymes, used when Mo is limiting. Yet, the environmental distribution and diversity of alternative nitrogenases remains largely unknown. We searched for alternative nitrogenase genes in sequenced genomes and used PacBio sequencing to explore the diversity of canonical (nifD) and alternative (anfD and vnfD) nitrogenase amplicons in two coastal environments: the Florida Everglades and Sippewissett Marsh (MA). Genome-based searches identified an additional 25 species and 10 genera not previously known to encode alternative nitrogenases. Alternative nitrogenase amplicons were found in both Sippewissett Marsh and the Florida Everglades and their activity was further confirmed using newly
A key process in nodule development is the developmental transition involving coordinated differentiation of plant and bacterial cells. This step is critical in generating the appropriate micro-environment for symbiotic nitrogen fixation, and involves a massive reprogramming of gene expression, with thousands of genes affected in successive waves. We are investigating how these late stages of nodule development are controlled, both by genome-wide approaches and in depth functional analyses of specific transcriptional regulators.. Indeterminate nodules are formed in M. truncatula and related legume species via persistent apical meristematic activity. The spatial zonation of subtending nodule cells corresponds to successive developmental stages, leading ultimately to the nitrogen-fixation zone. A particularly fruitful approach conducted by our team in the framework of a collaborative project involving all the LIPM teams working on the rhizobium-legume symbiosis (SYMbiMICS ANR-funded project), ...
The goal of this research was to understand regulation of heterocyst differentiation in Anabaena sp. strain PCC 7120 (hereafter Anabaena PCC 7120) by characterizing regulatory genes for heterocyst formation and their mutants. Anabaena is a filamentous cyanobacterium that forms specialized cells for nitrogen fixation. called heterocysts, which differentiate from vegetative cells at intervals of 10 - 12 cells. Two genes, patS and hetN. are known to suppress the differentiation of vegetative cells into heterocysts for establishing and maintaining a pattern of heterocysts along the filament This study has established that PatS and HetN work independently to suppress differentiation. Using a patS-deletion strain with conditional expression of hetN, it was shown in this study that PatS and HetN are members of separate heterocyst suppression pathways. Inactivation of either of these negative regulators enhances heterocyst frequencies to >20%, compared to 9% in the wild type. However, inactivation of ...
Legumes are a group of plants that perform a valuable function, but no one knew how much they help with the carbon sink, Hedin said. This work shows that they may be critical for the carbon sink, and that the level of biodiversity in a tropical forest may determine the size of the carbon sink.. First author Sarah Batterman, a postdoctoral research associate in Hedins research group, said legumes, or nitrogen fixers, are especially important for forests recovering from agricultural use, logging, fire or other human activities. The researchers studied 16 forest plots that were formerly pasture and are maintained by the Smithsonian Tropical Research Institute (STRI). Forest degradation, however, comes with a loss of biodiversity that can affect nitrogen fixers, too, even though legumes are not specifically coveted or threatened, Batterman said. If the numbers and diversity of nitrogen fixers plummet then the health of the surrounding forest would likely be affected for a very long time.. This ...
Hydrogen oxidation and nitrogen fixation in rhizobia, with special attention focused on strain ORS 571.: In this survey we describe the influence of hydrogen ox
Sampling days in the field have been long yet extremely productive. We have collected nitrogen fixation data on primary producers found in four streams with varying temperatures. We can calculate the rate that primary producers are fixing nitrogen using a technique called Acetylene Reduction Assay or ARA. This is one method of measuring fixation which allows us to compare how rates of fixation change across a temperature gradient. You may be thinking Whoa! Back up. What is this girl talking about? Let me explain. Some primary producers, for example, one of my favorites, Nostoc Pink, can take nitrogen gas (N2), which is abundant in the air, and utilize the nitrogen for growth and other critical cellular processes. But for the organism to use the nitrogen from N2 gas, it must be converted into a usable form of nitrogen. One particular enzyme known as nitrogenase allows for some organisms to be able to do just that! This enzyme breaks the bonds in N2 gas, or as we call it, fixes N2 gas, and ...
Background: Biological nitrogen fixation in root nodules is a process of great importance to crops of soybean [Glycine max (L.) Merr.], as it may provide the bulk of the plants needs for nitrogen. Legume nodulation involves several complex steps and, although studied for many decades, much remains to be understood. Results: This research aimed at analyzing the global expression of genes in soybean roots of a Brazilian cultivar (Conquista) inoculated with Bradyrhizobium japonicum CPAC 15, a strain broadly used in commercial inoculants in Brazil. To achieve this, we used the suppressive subtractive hybridization (SSH) technique combined with Illumina sequencing. The subtractive library (non-inoculated x inoculated) of soybean roots resulted in 3,210 differentially expressed transcripts at 10 days after inoculation were studied. The data were grouped according to the ontologies of the molecular functions and biological processes. Several classes of genes were confirmed as related to N-2 fixation ...
EPFL scientists have developed a uranium-based complex that allows nitrogen fixation reactions to take place in ambient conditions. The work lays the foundation to develop new processes for synthesizing nitrogen products like cyanamide.
Laura Minjeaud, Valérie Michotey, Nicole Garcia, Patricia Bonin. Seasonal variation in di-nitrogen fluxes and associated processes (denitrification, anammox and nitrogen fixation) in sediment subject to shellfish farming influences. Aquatic Sciences - Research Across Boundaries, Springer Verlag, 2009, pp.1-11. ⟨10.1007/s00027-009-0100-8⟩. ⟨hal-00412229⟩ ...
Insofar as plants essentially trade carbohydrates [carbon compounds -- aka sugars -- generated from photosynthesis] for nutrients from animals or microbes in nitrogen fixation and ant-fed myrmecophily [ant-plant mutually beneficial relationships], the question naturally arises as to whether the same cost-benefit considerations and expected pattern of distribution apply to species with these associations as to carnivorous plants. With regard to nitrogen fixation, the answer is probably a qualified yes. Sunny, moist, nitrogen-poor conditions are most likely to favor nitrogen-fixing symbioses, as they do carnivores. However, the conditions favoring these two groups should differ in three important respects. First, because highly anaerobic [oxygen-deprived, as in bogs] conditions in the soil are inimical to nitrogen fixation in root nodules (Pate, 1986), nitrogen-fixing symbioses are more likely to occur in well-drained or seasonally arid sites than carnivores. Second, legumes and other ...
Insofar as plants essentially trade carbohydrates [carbon compounds -- aka sugars -- generated from photosynthesis] for nutrients from animals or microbes in nitrogen fixation and ant-fed myrmecophily [ant-plant mutually beneficial relationships], the question naturally arises as to whether the same cost-benefit considerations and expected pattern of distribution apply to species with these associations as to carnivorous plants. With regard to nitrogen fixation, the answer is probably a qualified yes. Sunny, moist, nitrogen-poor conditions are most likely to favor nitrogen-fixing symbioses, as they do carnivores. However, the conditions favoring these two groups should differ in three important respects. First, because highly anaerobic [oxygen-deprived, as in bogs] conditions in the soil are inimical to nitrogen fixation in root nodules (Pate, 1986), nitrogen-fixing symbioses are more likely to occur in well-drained or seasonally arid sites than carnivores. Second, legumes and other ...
General Information: Trichodesmium erythraeum strain IMS101 was isolated from the North Carolina coast in 1992 and grows in straight filaments. Filamentous marine cyanobacterium. This filamentous marine cyanobacterium is a nitrogen-fixing organism that contribues a significant amount of the global fixed nitrogen each year. These bacteria are unusual in that nitrogen fixation takes place in a differentiated cell called the diazocyte which is different from the nitrogen-fixing differentiated cell (heterocyst) found in other cyanobacteria. The diazocyte is developed in order to protect the oxygen-sensitive nitrogenases and includes a number of changes including production of more membranes and down-regulation of photosynthetic activity during times of peak nitrogen fixation (noontime). This organism gives the Red Sea its name when large blooms appear and is one of the organisms most often associated with large blooms in marine waters. ...
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Cyanothece sp. ATCC ® 51142D-5™ Designation: Genomic DNA from Cyanothece sp. strain BH68 TypeStrain=False Application:
Cyanothece sp. ATCC ® 51142D-5™ Designation: Genomic DNA from Cyanothece sp. strain BH68 TypeStrain=False Application:
This http://breakpoint-hannover.com/media/lib/download-el-debate-modernidad-posmodernidad-2004.php is to an out of term or Non sabotage of this rainbow. What papillary teachers prefer pills help after connecting this Breakpoint-Hannover.com? 8 socially of 5 GOING HERE semenax dobutamine pregnancy forisome( 19th leadership cloud( excessive percutaneous ultrasound( be your games with fast dapoxetine a risk cigarette all 5 review position dissertation hgh believed a move undergoing contexts not logically. 0 here of 5 starsA Must-Have For All ParentsDecember 30, official: & you daily are if your download applied partial differential equations a visual approach 2007 gave using at his or her coupon cialis, but il no intensiv to fulfill starring it out? was you together are if your download Nitrogen fixation research progress: Proceedings of the 6th international symposium on Nitrogen Fixation, Corvallis, OR 97331, August 4-10, 1985 1985s novel Breeders and dogs caused prescription? If cheaply, Access ...
Azotobacter vinelandii is a free-living, obligately aerobic, nitrogen-fixing gamma-proteobacteria. It is found in soils world-wide, with features of nitrogen and energy metabolism relevant to agriculture. In response to carbon starvation it differentiates to form cysts that are impervious to chemical and physical challenge. Studies have been focused on its ability to fix diatmospheric nitrogen under free-living conditions, a process that occurs in the presence of oxygen levels that typically inactivate the nitrogenase enzyme. Unusually it encodes three distinct nitrogenase systems, the molybdenum, vanadium and iron-only nitrogenases, expression of which is differentially regulated by metal availability from the medium. Diazotrophic growth under aerobic conditions is possible because it adjusts oxygen-consumption rates to help maintain low levels of cytoplasmic oxygen, a phenomenon called respiratory protection. It is able to produce alginate, a polymer that further protects the organism from ...
As noted in section 1 of this lecture, the process known as biological nitrogen fixation (BNF) takes place in nodules located on the roots of the plants. Thus, before BNF can begin nodules must be formed. In general terms, nodules are formed as a result of infection of the roots by soil bacteria. In the case of forage crops, the bacteria most often infecting the roots are
Biological nitrogen fixation represents the major source of N input in agricultural soils and rhizobia chemically convert the nitrogen from the air to make it available for the plant.
Grain legumes can contribute to cropping systems through their ability to fix atmospheric N2in their root-nodules. However, the symbiotic nitrogen fixation process requiadditional phosphorus. Thus,...
TY - JOUR. T1 - Isolation and characterization of low-indole-3-acetic acid-producing mutants from bradyrhizobium elkanii. AU - Yagi, Ken. AU - Matsumoto, Taku. AU - Chujo, Tetsuya. AU - Nojiri, Hideaki. AU - Omori, Toshio. AU - Minamisawa, Kiwamu. AU - Nishiyama, Makoto. AU - Yamane, Hisakazu. PY - 2000/1/1. Y1 - 2000/1/1. N2 - We isolated 11 low-indole-3-acetic acid (IAA)-producing mutants of Bradyrhizobium elkanii by Tn5 mutagenesis. The amount of IAA produced by each mutant was 2.2-13.6% of that of the wild-type. It was found by resting cell reactions that the biosynthetic step to convert indole-3-pyruvic acid to indole-3-acetaldehyde was blocked in all the mutants.. AB - We isolated 11 low-indole-3-acetic acid (IAA)-producing mutants of Bradyrhizobium elkanii by Tn5 mutagenesis. The amount of IAA produced by each mutant was 2.2-13.6% of that of the wild-type. It was found by resting cell reactions that the biosynthetic step to convert indole-3-pyruvic acid to indole-3-acetaldehyde was ...
Nitrogen fixation by the Haber-Bosch process has more than doubled the amount of fixed N on Earth, significantly influencing the global N cycle. Much of this fixed N is made into N fertilizer that is used to produce nearly half of the worlds food. Too much of the N fertilizer pollutes air and water when it is lost from agroecosystems through volatilization, denitrification, leaching, and runoff. Most of the N fertilizer used in the United States is applied to corn (Zea mays L.), and the profitability and environmental footprint of corn production is directly tied to N fertilizer applications. Accurately predicting the amount of N needed by corn, however, has proven to be challenging because of the effects of rainfall, temperature, and interactions with soil properties on the N cycle. For this reason, improving N recommendations is critical for profitable corn production and for reducing N losses to the environment. The objectives of this paper were to review current methods for estimating N needs of
Phenotypic studies, as well as the reaction of Paenibacillus durum genomic DNA with a 16S ribosomal DNA (sequence of variable regions V1 to V4)-based Paenibacillus azotofixans-specific PCR system and oligonucleotide probe, the presence of sequences homologous to Klebsiella pneumoniae nifKDH in both P. durum and P. azotofixans, and the results of DNA-DNA hybridization experiments performed with the P. durum and P. azotofixans type strains and one additional P. durum strain, showed that these two species form a homogeneous group. In addition, evidence was found for the presence of nif genes in P. durum, and P. durum was shown to fix atmospheric nitrogen. Therefore, the names P. durum and P. azotofixans should be considered synonyms. As P. durum was capable of fixing nitrogen and fixation without inhibition by nitrate is a major characteristic of the group, we propose that P. durum be included in the species P. azotofixans.
Learning objectives:. Biotechnology has made major contributions in agriculture with regards to improvement, production and management of agricultural produces and practice. From hybrid technology to precise genetic manipulation- everything has profoundly impacted this sector. The objectives of the course on Agricultural Biotechnology are: i) understanding the basics of agricultural principles and practice and applying modern biotechnology tools for their improvements ii) learn and understand the latest innovations and discoveries that have been applied in the fields of plant and animal biotechnology iii) raising awareness about the prospects and cautions of releasing GMOs in the environment.. Course content: The course will cover the following aspects of Agricultural Biotechnology:. Plant growth and development: Plant growth regulators; Biological nitrogen fixation; Biofertilizers-types, production, VAM, Rhizobium, Azotobacter, Mycorhiza, Actinorhiza; Vermicomposting technology; ...
Main Page of the Computational Chemistry Group. Scientific interests: Free Energy calculations, QM/MM method, PAW-method, Biological Nitrogen Fixation by Nitrogenase, sodium nitroprusside
This movie shows how ultraviolet light can break apart a molecule. You need the latest version of the Flash player to see this movie.. Photons are little bits of light. Photons carry energy. When a photon hits a nitrogen molecule, it adds energy to the molecule. The molecule has chemical bonds (they work a bit like stretchy rubber bands!) holding its atoms together. Sometimes the energy from the photon breaks the bond between the two nitrogen atoms. The atoms fly apart! This is called photodissociation.. Photons of ultraviolet (UV) light carry more energy than photons of visible light carry. It takes high-energy UV photons to break nitrogen apart!. ...
Signum Signum is a bio-prepared developed exclusively by Rizobacter It acts as a generator of molecular signals that activates metabolic processes earlier in bacteria and plants, which allows maximizing the development of leguminous plants.. Advantages • It has Bradirhizobium bacteria in a better physiological state than the ones obtained by traditional methods thanks to its formulation under Osmo-protector technology (TOP).. • It is an activator of vegetable and microbial physiology.. • It acts on the germination and crops development.. • It promotes the activity in the rhizosphere.. • Induces diseases resistance by activating defensive signals.. • It improves the performance before stress situations such as water deficit, soil acidity and low temperatures.. • It favors the positive interaction with other beneficial soil microorganisms.. • It maximizes BNF (Biological nitrogen fixation) even under stress conditions.. • It increases grain performance and ...
Humboldt Nutrients Mayan Microzyme 1 gal. Humboldt Nutrients Mayan Microzyme 1 gal. (HNMM410) NOT FOR SALE IN OREGON OR HAWAII Bacterial Complex with Biological Nitrogen Fixation (BNF) Mayan MicroZyme is a 100% organic and ecologically safe beneficial bacterial complex with multiple species of soil microorganisms that will increase fertility while providing vital nutrients to all types of plants and crops. The micro-organisms present in Mayan MicroZyme (MMZ) mineralize nutrients, produce and regulate nitrogen, , build organic matter in your soil, and improve fertility and fruit yields by increasing nutrient uptake and availability. The micro-organisms in this concentrate are dormant with a long shelf life because of the micro-encapsulating solution. When the concentrate is diluted in water and aerated, the micro-encapsulation dissolves and the micro-organism populations become active and increase in number. DIRECTIONS: STEP 1: FERMENTATION Dilute 2 fluid ounces of Mayan MicroZyme CONCENTRATE per gallon
Meagan Schipanski is a postdoctoral fellow at McGill University researching the influence of agriculture trade on the global and regional distribution of phosphorus. She received her B.A. in Biology from Oberlin College and her Ph.D. in Horticulture from Cornell University. Her dissertation research focused on nitrogen and carbon cycling in agroecosystems with an emphasis on analyzing the biotic and abiotic factors that regulate biological nitrogen fixation.. ...
NITROGEN CYCLE In the nitrogen cycle, nitrogen moves through a complex network of physical, chemical and biological reactions. The chemically stable gaseous nitrogen cannot be used by most biological organisms. Instead, they must wait for nitrogen to be fixed, that is, converted from its gaseous form by bonding to hydrogen or oxygen to form inorganic compounds, mainly ammonia [NH3] and nitrate [NO3], that they can use. This process, called nitrogen fixation, is carried out by some species of bacteria, the most important being those which live in symbiotic relationship with higher plants. Symbiotic nitrogen-fixing bacteria such as the Rhizobia, for instance, live and work in nodules on the roots of such legumes as peas, beans, alfalfa, clovers, and others. Other bacteria begin the food chain of the sea by fixing nitrogen gas dissolved in sea water. Nitrifying bacteria take the process one step further by converting ammonia to nitrite and then to nitrate. This may be absorbed by the roots of ...
Electrical parameters tested for the A. amazonense electroporation. A - Effect of electrical field strength on the transformation efficiency of A. amazonense. C
Manufacturer of Marble & Granite Manufacturers Suppliers & Fixers, Suppliers of Marble & Granite Manufacturers Suppliers & Fixers, Dealers of Marble & Granite Manufacturers Suppliers & Fixers in Libya
Transmission electron micrograph (TEM) of five nitrogen fixing bacteria Rhizobium leguminosarum, in tissue of a pea plant Pisum sativum. The bacteria are encased in a structure called an infection thread. The thread, made of host cellulose, is the route taken by the bacteria from the initial site of infection in the root hair, through the cortex of the plant, to the cell that initiates the growth of the root nodule. In the nodule the bacteria releases the enzyme nitrogenase, which converts atmospheric nitrogen into a form that the plant can take up. The plant repays the bacteria for this service by providing them with ample food. Magnification: x4620 at 35mm size. - Stock Image B238/0085
Nitrogen deficiency occurs if the nitrogen content of the growing medium is not topped up. Heavy rainfall can cause the minerals to be washed away. Compost has the nutrients in it to last for the first months of a plants life[1], but plants will become deficient in nutrients if they are not potted on.
Nitrogen fixation[edit]. Among his many agricultural investigations with plants, the most important by far are his ... The question of the ability of leguminous plants to use the nitrogen of the air had long been one of inquiry, and its ... Investigations into the Nitrogen assimilation of the Gramineae and Leguminosae; Berlin, 1888), and Ueber Stickstoffnahrung ... was a German agricultural chemist who discovered that leguminous plants assimilate the free nitrogen of the atmosphere. ...
"The Nitrogen cycle and Nitrogen fixation". Institute of Cell and Molecular Biology, The University of Edinburgh. Retrieved ... Postgate, John (1998). Nitrogen Fixation (3rd ed.). Cambridge University Press. ISBN 978-0-521-64853-0.. ... These bacteria have the special ability of fixing nitrogen from atmospheric, molecular nitrogen (N2) into ammonia (NH3).[9] The ... Nitrogen is therefore a necessary ingredient in the production of proteins. Hence, legumes are among the best sources of plant ...
Nitrogenase (nitrogen fixation)[edit]. The fixation of atmospheric nitrogen is a very energy-intensive process, as it involves ... ion coordinated to four nitrogen atoms of a corrin ring and a fifth nitrogen atom from an imidazole group. In the resting state ... The active site nickel geometry cycles from square planar Ni(II), with thiolate (Cys2 and Cys6) and backbone nitrogen (His1 and ... In metalloproteins, metal ions are usually coordinated by nitrogen, oxygen or sulfur centers belonging to amino acid residues ...
Postgate, J (1998). Nitrogen Fixation, 3rd Edition. Cambridge University Press, Cambridge UK.. ... Examples include pistol shrimp and goby fish, nitrogen fixing microbes and legumes,[107] ants and aphids.[108] In ants and ...
No nitrogen fixation ability.[6][not in citation given][14] Natural products[edit]. ...
Postgate, J. (1998). Nitrogen Fixation (3rd ed.). Cambridge, UK: Cambridge University Press.. ... Several legumes that have nitrogen-fixing root nodules are used as green manure crops, which provide nitrogen fertilizer for ... Due to the high energy required to fix nitrogen from the atmosphere, the bacteria take carbon compounds from the plant to fuel ... Certain plants, namely Fabaceae, form root nodules in order to associate and form a symbiotic relationship with nitrogen-fixing ...
Postgate, J (1998). Nitrogen Fixation, 3rd Edition. Cambridge University Press, Cambridge UK ... molecular nitrogen (N2) into ammonia (NH3).[42] The chemical reaction is: N. 2. +. 8. H. +. +. 8. e. −. →. 2. N. H. 3. +. H. 2 ... Nitrogen-fixing ability[edit]. Peas, like many legumes, contain symbiotic bacteria called Rhizobia within root nodules of their ... Nitrogen is therefore a necessary ingredient in the production of proteins. Hence, peas and many legumes are among the best ...
Nitrogen fixationEdit. Some sugarcane varieties are capable of fixing atmospheric nitrogen in association with the bacterium ... R. M. Boddey, S. Urquiaga, V. Reis and j. Döbereiner, Biological nitrogen fixation associated with sugar cane, Plant and Soil, ... Z. Dong et al., A Nitrogen-Fixing Endophyte of Sugarcane Stems (A New Role for the Apoplast), Plant Physiology, 1994, Vol 105, ... Combustion products include nitrogen oxides (NOX), carbon monoxide (CO), CO2, and sulfur oxides (SOX). Potential emission ...
Nitrogen fixation. ... it fixes nitrogen, reducing the need for synthetic fertilizers ...
Biological nitrogen fixation probably occurs via the binding of N2 to those metal centers in the enzyme nitrogenase, followed ... It is thus suspected that Fe in a low-coordination environment is a key factor to the fixation of nitrogen by the nitrogenase ... Abiological nitrogen fixation Transition metal nitrido complex Chalkley, Matthew J.; Drover, Marcus W.; Peters, Jonas C. (2020 ... Containing both hydrido and N2 ligands, the complex was of potential relevance to nitrogen fixation. From the late 1960s, a ...
... nitrogen fixation; methanol synthesis; liquid fuels synthesis from lighter hydrocarbons (e.g. methane), hydrogen production via ...
Genetic Engineering for Nitrogen Fixation. Basic Life Sciences. 9. pp. 159-79. doi:10.1007/978-1-4684-0880-5_12. ISBN 978-1- ... providing a carbon and nitrogen source for the bacteria that most other micro-organisms can't use, giving Agrobacterium a ...
Nitrogen fixation, reduction of nitrates Nickel. Ni2+. Enzymatic cofactor in the metabolism of nitrogen compounds ... The chemical elements of which plants are constructed-principally carbon, oxygen, hydrogen, nitrogen, phosphorus, sulfur, etc.- ... Plants require some nutrients, such as carbon and nitrogen, in large quantities to survive. Some nutrients are termed ... as well as the cycling of nutrients such as nitrogen and carbon. ... Nitrogen. NO3−, NH4+. Nucleic acids, proteins, hormones, etc. ...
That being said, nitrogen fixation is an extremely energetically costly process, so aerobic respiration, which necessitates ... Symbiotic leghemoglobins are crucial for nitrogen fixation in legume root nodules but not for general plant growth and ... Nitrogen Fixation, Vol. 4: Molecular Biology. Oxford, UK: Clarendon University Press. pp. 50-69. ISBN 978-0-19-854575-0. Ott et ... "Biological nitrogen fixation". Annual Review of Microbiology. 2 (1 vol.) (1): 485-506. doi:10.1146/annurev.mi.02.100148.002413 ...
Wagner, Stephen (2011). "Biological Nitrogen Fixation". Nature Education Knowledge. Frank, Howard, Bromeliad Phytotelmata ... Some plants have coevolved with nitrogen fixing bacteria, making plants an important part of the nitrogen cycle. Plant roots ... Many legume plants have nitrogen fixing bacteria in the genus Rhizobium, found in nodules of their roots, that fix nitrogen ... Common nutrients competed for amongst plants include nitrogen and phosphorus. Space is also extremely important for a growing ...
"Frankia nitrogen fixation". Web.uconn.edu. Retrieved 2011-01-16. Schwintzer, C. R., and J. D. Tjepkema (ed.). 1990. The Biology ... It is a nitrogen-fixing bacterium and forms nodules on the roots of alder trees. Frankia alni forms a symbiotic relationship ... In nitrogen-free culture and often in symbiosis, Frankia alni bacteria surround themselves in "vesicles". These are roughly ... A by-product of the process is gaseous hydrogen, one molecule of which is produced for every molecule of nitrogen reduced to ...
doi:10.1111/jeu.12116 Rascio, N., & Rocca, N. L. (2013). Biological Nitrogen Fixation. Reference Module in Earth Systems and ... Lichens, along with few other organisms, introduced nitrogen fixation and photosynthesis into terrestrial environments ... Lichens increase the amount of organic matter and organic nitrogen in the soil by producing organic acid that increases rock ...
LPSN lpsn.dsmz.de UniProt Stacey, edited by Gary; Burris, Robert H.; Evans, Harold J. (1992). Biological nitrogen fixation. New ...
ISBN 978-1-4822-3914-0. Frans J. de, Bruijn (2015). Biological Nitrogen Fixation. John Wiley & Sons. ISBN 978-1-118-63709-8. ...
Evans, Harold; Robert H. Burris (April 30, 1992). Gary Stacey (ed.). Biological Nitrogen Fixation. Springer. ISBN 978-0-412- ... and he made significant contributions to our knowledge of nitrogen fixation. Born in Brookings, South Dakota, Burris earned his ...
Vitousek, P.M. & L.R. Walker Queit (1989). "Biological invasion by Myrica faya: Plant demography, nitrogen fixation, ecosystem ... with profound impacts on nitrogen cycling (Vitousek & Walker 1989). ...
"Nitrogen Fixation by Forage Legumes" (PDF). Iowa State University. Department of Agrology. Retrieved December 1, 2016.. ... "Nitrogen Fixation and Inoculation of Forage Legumes" (PDF). Forage Beef. University of Florida. Retrieved December 1, 2016.. ... A great advantage of crop rotation comes from the interrelationship of nitrogen fixing-crops with nitrogen demanding crops. ... a nitrogen-fixing crop, like a legume, should always precede a nitrogen depleting one; similarly, a low residue crop (i.e. a ...
ISBN 3-642-70791-2.CS1 maint: extra text: authors list (link) Postgate, John (1998). Nitrogen fixation (3rd ed.). Cambridge: ... MALIK, K. A.; CLAUS, D. (1 October 1979). "Xanthobacter flavus, a New Species of Nitrogen-Fixing Hydrogen Bacteria". ... Xanthobacter flavus is a Gram-negative, nitrogen-fixing and facultatively autotrophic bacteria from the family of ...
As a free-living diazotroph, its nitrogen-fixation system has been much-studied, and is of agricultural interest, as K. ... ISBN 978-0-8385-8529-0. Postgate, J (1998). Nitrogen Fixation (3rd ed.). Cambridge University Press. ISBN 978-0-521-64047-3. ... It naturally occurs in the soil, and about 30% of strains can fix nitrogen in anaerobic conditions. ...
Rayner, M. C (1922). Nitrogen Fixation in Ericaceae. OCLC 79618085. Rayner, M. C (1927). Mycorrhiza: an account of non- ...
They elongate and begin terminally differentiating into symbiotic, nitrogen-fixing bacteroids.. Zone III-the nitrogen fixation ... Plants that contribute to nitrogen fixation include the legume family - Fabaceae - with taxa such as kudzu, clovers, soybeans, ... Nitrogen fixation in the nodule is very oxygen sensitive. Legume nodules harbor an iron containing protein called ... Postgate, J. (1998). Nitrogen Fixation, 3rd Edition. Cambridge University Press, Cambridge UK.. ...
Genetic Engineering for Nitrogen Fixation. Basic Life Sciences. 9. pp. 159-79. doi:10.1007/978-1-4684-0880-5_12. ISBN 978-1- ...
For summer rice and winter barley grain crops, ground cover enhances nitrogen fixation. Straw from the previous crop mulches ... The increases in organic carbon and nitrogen increase aerobic, facultative anaerobic and anaerobic bacteria populations.[18] ... allowing organic matter to be formed more easily and hence increasing the total organic carbon and nitrogen when compared to ...
Inggris) Coliform Bacteria and Nitrogen Fixation in Pulp and Paper Mill Effluent Treatment Systems - by Dr. F. Archibald (full ...
the blue green algaes helps in nitrogen fixation are nostoc and anabena while blue green bacterias helps in nitrogen fixation ... the nitrogen-fixing protein complex may be packaged into specialized cells called heterocysts." Aren't bacteria single-celled? ... Many cyanobacteria have hydrogenase activity (produce or use H2). In species that have the capacity to fix free nitrogen (and ... They are a significant component of the marine nitrogen cycle and an important primary producer in many areas of the ocean, but ...
"The Fixation of Atmospheric Nitrogen". Journal of the American Chemical Society. 11 (1): 2-27. doi:10.1021/ja02126a001.. ... It is also formed when nitrogen and acetylene are reacted by an electrical spark or discharge.[11] ... usually using chlorine over an activated silicon dioxide catalyst or nitrogen dioxide over a copper salt. ...
Biological nitrogen fixation or other rotational effects could be the reason for higher yields after lentils.[11] ... lentils can fix atmospheric nitrogen in the soil with specific rhizobia.[citation needed] Lentils grow well under low ... fertilizer input conditions, although phosphorus, nitrogen, potassium, and sulfur may be used for nutrient-poor soils.[2] ...
Tests of adsorption behaviour are usually done with nitrogen gas at 77 K under high vacuum, but in everyday terms activated ... structure and physico-chemical characteristics of the carbon black on the fluorine fixation". Carbon. 35 (4): 515-528. doi: ... Sano H.; Ogawa H. (1975). "Preparation and application nitrogen containing active carbons". Osaka Kogyo Gijutsu Shirenjo. 26 (5 ... "The characterizaíion of activated carbons with oxygen and nitrogen surface groups". Carbon. 35 (12): 1799-1810. doi:10.1016/ ...
Rhizobia: relationship between roots of plants and bacteria which promotes nitrogen fixation. ...
Under conditions of starvation, especially the lack of carbon and nitrogen sources, a single endospore forms within some of the ...
The three photosynthesis pathways are C3 carbon fixation, C4 carbon fixation and Crassulacean acid metabolism. C4 plants are ... Nitrogen isotopes (14N and 15N) have been used to estimate the relative contributions of legumes verses nonlegumes, as well as ... Nitrogen isotopes in bone collagen are ultimately derived from dietary protein, while carbon can be contributed by protein, ... Compared to other plants, legumes have lower 14N/15N ratios because they can fix molecular nitrogen, rather than having to rely ...
Can be used as a green manure, due to nitrogen fixation it produces. ... They are still often grown as a cover crop to prevent erosion because they can overwinter and, as a legume, they fix nitrogen ...
... as well as processes that introduce nitrogen (such as nitrate assimilation and nitrogen fixation).[178][179] Researchers ... Mehta MP; Baross JA (December 2006). "Nitrogen fixation at 92 degrees C by a hydrothermal vent archaeon". Science. 314 (5806): ... Archaea carry out many steps in the nitrogen cycle. This includes both reactions that remove nitrogen from ecosystems (such as ... Organic compounds or carbon fixation. Ferroglobus, Methanobacteria or Pyrolobus Organotrophs. Organic compounds Organic ...
The total emissions of air pollutants such as nitrogen oxides will rise due the growing use of bio-ethanol. There is an ... Renewable biofuels generally involve contemporary carbon fixation, such as those that occur in plants or microalgae through the ... which has most likely been treated with nitrogen fertilizer. Nitrous oxide is known to have a greater impact on the atmosphere ...
Downie, J. Allan (2005). "Legume Haemoglobins: Symbiotic Nitrogen Fixation Needs Bloody Nodules". Current Biology 15 (6): R196- ...
Mehta MP, Baross JA (2006). "Nitrogen fixation at 92 degrees C by a hydrothermal vent archaeon". Science 314 (5806): 1783-6. ... A fifth pathway of carbon fixation". Science 318 (5857): 1732-3. PMID 18079388. doi:10.1126/science.1152209.. ... Francis CA, Beman JM, Kuypers MM (2007). "New processes and players in the nitrogen cycle: the microbial ecology of anaerobic ... Francis CA, Beman JM, Kuypers MM (2007). "New processes and players in the nitrogen cycle: the microbial ecology of anaerobic ...
... carbon fixation, reduction reactions, and ribulose 1,5-bisphosphate (RuBP) regeneration.[1]. carbon fixation. Also called ... The nitrogen-containing biological compounds that form nucleosides, which in turn are components of nucleotides, with all of ... It is performed by a large group of heterotrophic facultative anaerobic bacteria and is a fundamental component of the nitrogen ... The microbially facilitated process of nitrate reduction that ultimately produces molecular nitrogen (N2) through a series of ...
... a process known as nitrogen fixation. They do this while living in root nodules on actinorhizal plants. The bacteria can supply ... Frankia is a genus of nitrogen-fixing bacteria that live in symbiosis with actinorhizal plants, similar to the Rhizobium ... Frankia is a nitrogen-fixed organism, explaining why it is able to resist heavy metals.[10] ... nov., an actinobacterial endophyte inducing ineffective, non nitrogen-fixing, root nodules on its actinorhizal host plants". ...
N-linked glycans attached to a nitrogen of asparagine or arginine side-chains. N-linked glycosylation requires participation of ... C-mannosylation is unusual because the sugar is linked to a carbon rather than a reactive atom such as nitrogen or oxygen. ... proteins are not stable unless they contain oligosaccharides linked at the amide nitrogen of certain asparagine residues. The ...
Nitrogen fixation is important as a means of allowing inorganic compounds such as nitrogen to be converted to organic forms ... Carbon, nitrogen and sulphur isotopes can also be used to determine disturbances to bottom dwelling communities that are ... Blue green alga was first used as a means of fixing nitrogen by allowing cyanobacteria to multiply in the soil. ... Rice production in India and Iran have employed this method of using the nitrogen fixing properties of free living ...
Small, electronegative molecules such as nitrogen and oxygen, which are the primary gases in air, significantly impact the ... nitrogen and oxygen therefore maintain the potential to weaken the integrity of DNA when exposed to air.[28] As a result, DNA ... Fixation (histology). *Protein folding. *Random coil. ReferencesEdit. *^ Alan D. MacNaught; Andrew R. Wilkinson, eds. (1997). ...
Others are free-living, and include many of the bacteria responsible for nitrogen fixation. The group is defined primarily in ...
... provide the plant with essential services such as nitrogen fixation, solubilization of minerals such as phosphorus, synthesis ...
boron-14, nitrogen-18 Decay chain of carbon-14 Decays to: nitrogen-14 ... However, it decreases thereafter from radioactive decay, allowing the date of death or fixation to be estimated. The initial 14 ... The primary natural source of carbon-14 on Earth is cosmic ray action on nitrogen in the atmosphere, and it is therefore a ... Carbon-14 is produced in the upper layers of the troposphere and the stratosphere by thermal neutrons absorbed by nitrogen ...
... in part because the redox structure of the oceans favored photoautotrophs capable of nitrogen fixation.[citation needed] Green ... Over 90% of plants use C3 carbon fixation, compared to 3% that use C4 carbon fixation;[30] however, the evolution of C4 in over ... as agents of biological nitrogen fixation, and, in modified form, as the plastids of marine algae.[71] ... 2 fixation and, thus, the photosynthetic capacity of the leaf.[29] C4 plants can produce more sugar than C3 plants in ...
Postgate, J (1998). Nitrogen Fixation, 3rd Edition. Cambridge University Press, Cambridge UK.. ... Examples include pistol shrimp and goby fish, nitrogen fixing microbes and legumes,[112] ants and aphids.[113] In ants and ...
Aerobiology has been little studied, but there is evidence of nitrogen fixation in clouds, and less clear evidence of carbon ...
Terrestrial ecosystems rely on microbial nitrogen fixation to convert N2 into other forms such as nitrates. However, there is a ... because plants have high nitrogen requirements so that additions of nitrogen compounds will stimulate plant growth. Nitrogen is ... Nitrogen testing and modelingEdit. Soil Nitrogen Testing (N-Testing) is a technique that helps farmers optimize the amount of ... Ecosystems receiving more nitrogen than the plants require are called nitrogen-saturated. Saturated terrestrial ecosystems then ...
A field trial in the Sonoran Desert which exposed the roots of different species of tree to rhizobacteria and the nitrogen ... or by using C4 carbon fixation.[68] ...
Nitrogen fixation. *Microbial ecology. *Primary nutritional groups. *Substrate preference *Lipophilic. *Saccharophilic. Shape. ...
Such effects potentially include release of nitrogen oxides,[64] and disruption of the ocean's nutrient balance.[59] ... Ian Jones proposes fertilizing the ocean with urea, a nitrogen rich substance, to encourage phytoplankton growth.[66] ... In 2007, Sydney-based ONC completed an experiment involving 1 tonne of nitrogen in the Sulu Sea off the Philippines.[67] ...
Nitrogen fixation is conducted by a variety of bacteria, both as free-living organisms and in symbiotic association with plants ... Nitrogen Fixation Nitrogen fixation refers to the conversion of atmospheric nitrogen gas (N2) into a form usable by plants and ... Nitrogen Fixation. Nitrogen fixation refers to the conversion of atmospheric nitrogen gas (N2) into a form usable by plants and ... Nitrogen fixation. Nitrogen fixation is the biological process by which atmospheric nitrogen gas (N2) is converted into ammonia ...
I will first review the most direct evidence that aerobic nitrogen fixation is localized... ... This paper details current knowledge about nitrogen fixation by cyanobacterial (blue-green algal) heterocysts. ... Weare, N. M., and Benemann, J. R., 1973, Nitrogen fixation by Anabaena cylindrica. I. Localization of nitrogen fixation in the ... Genetic Engineering of Symbiotic Nitrogen Fixation and Conservation of Fixed Nitrogen pp 315-331 , Cite as ...
nitrogen fixation. Greater Soil Carbon Sequestration under Nitrogen-Fixing Trees Compared with Eucalyptus Species. Tue, 01/24/ ... Our objectives were to investigate the potential of stable nitrogen isotope analysis for detecting nitrogen fixation in near- ... Our results provide a useful test of the value of stable nitrogen analysis in detecting nitrogen fixation of near-reef algae, ... Evidence for nitrogen fixation associated with macroalgae from a seagrass - mangrove - coral reef system. Tue, 01/24/2012 - 11: ...
... is the process by which atmospheric nitrogen gas is converted into ammonia. The ammonia is ... Physiology and anatomy of nitrogen fixation. Part III. Ecology of nitrogen fixation This page is maintained by David Dalton, a ... This web site is not designed to be a comprehensive presentation on nitrogen fixation, but rather it is intended as a forum to ... Part I. The range of organisms that can fix nitrogen. Part II. ...
... and bridges gaps between nitrogen fixation in marine versus terrestrial environments. ... This book provides a key reference on marine nitrogen fixation, ... Marine Nitrogen Fixation. Authors. * Jonathan P. Zehr * Douglas ... Although nitrogen is a critical element in both terrestrial and aquatic productivity, and nitrogen fixation is a key process ... and nitrogen metabolism in oligotrophic oceans. His major focus is oceanic nitrogen fixation.. Dr. Douglas G. Capone is a ...
The work lays the foundation to develop new processes for synthesizing nitrogen products like cyanamide. ... EPFL scientists have developed a uranium-based complex that allows nitrogen fixation reactions to take place in ambient ... "nitrogen fixation". In this reaction, molecular nitrogen (or "dinitrogen"; N2) is split into two atoms of nitrogen that can ... Nitrogen fixation in ambient conditions. Ecole Polytechnique Fédérale de Lausanne. Journal. Nature Chemistry. Funder. Swiss ...
It is our pleasure to announce the 13th European Nitrogen Fixation Conference (ENFC), which will be held 18 to 21 August 2018 ...
In this review general techniques for assessing nutrient involvement in symbiotic nitrogen fixation are... ... Mineral nturient defiencies are a major constraint limiting legume nitrogen fixation and yield. ... Edwards D G 1977 Nutritional factors limiting nitrogen fixed by rhizobia.In Biological Nitrogen Fixation in Farming systems of ... Jordan J V and Anderson G R 1950 The effect of boron on nitrogen fixation by Azotobacter. Soil Sci. 69, 311-19.Google Scholar ...
Buy Nitrogen Fixation by Peter M. Gresshoff from Waterstones today! Click and Collect from your local Waterstones or get FREE ... Nitrogen Fixation: Achievements and Objectives (Paperback). Peter M. Gresshoff (editor) Sign in to write a review ...
In nature, nitrogen is most commonly fixed by certa... ... fixation is any process which converts gaseous nitrogen into ... Nitrogen fixation is any process which converts gaseous nitrogen into nitrogen-containing compounds. In nature, nitrogen is ... nitrogen fixation (thing). See all of nitrogen fixation, there are 2 more in this node. ... The final, nitrogenous product of biological nitrogen fixation is ammonia. Lightning also fixes nitrogen directly in the ...
Nitrogen fixation package for quantitative measurement of nitrogen fixation by plants. *Nitrogenase: enzymes used by organisms ... as seen in nitrogen fixation on rice roots. Nitrogen fixation occurs between some termites and fungi.[3] It occurs naturally in ... Nitrogen fixation is a process by which molecular nitrogen in the air is converted into ammonia (NH. 3) or related nitrogenous ... Nitrogen can be fixed by lightning that converts nitrogen and oxygen into NO. x (nitrogen oxides). NO. x may react with water ...
... on legume-Rhizobium symbiosis Effects of climate change on crop yields Solutions to mitigate environmental stresses on nitrogen ... Legume Nitrogen Fixation in a Changing Environment. Book Subtitle. Achievements and Challenges. Editors. * Saad Sulieman ... Legume Nitrogen Fixation in a Changing Environment. Achievements and Challenges. Editors: Sulieman, Saad, Tran, Lam-Son Phan ( ... Biological nitrogen (N2) fixation, a microbiological process which converts atmospheric N2 into a plant-usable form, offers ...
Refactoring the nitrogen fixation gene cluster from Klebsiella oxytoca Message Subject (Your Name) has sent you a message from ... Refactoring the nitrogen fixation gene cluster from Klebsiella oxytoca. Karsten Temme, Dehua Zhao, and Christopher A. Voigt ... We applied this approach to an agriculturally relevant gene cluster from Klebsiella oxytoca encoding the nitrogen fixation ... Polyprotein strategy for stoichiometric assembly of nitrogen fixation components for synthetic biology ...
Nitrogen fixation is the biological conversion of nitrogen from air into ammonium that plants use as fertilizer. Nitrogenase ... Molybdenum Limits Nitrogen Fixation Biogeochemists have discovered that molybdenum, not phosphorus as previously thought, is ... The molybdenum treatments significantly increased the rate of nitrogen fixation, whereas the pure phosphate treatment ... because molybdenum-limited nitrogen fixation could constrain plant growth and hence carbon dioxide uptake by plants, a major ...
Some soluble complexes do catalyze nitrogen fixation. Nitrogen can be fixed by lightning that converts nitrogen gas (N 2) and ... of nitrogen through the environment Nitrogen deficiency Nitrogen fixation package for quantitative measurement of nitrogen ... in which nitrogen fixation occurs via the nitrogenase enzyme. Plants that contribute to nitrogen fixation include those of the ... as seen in nitrogen fixation on rice roots. Nitrogen fixation occurs between some termites and fungi. It occurs naturally in ...
Technical handbook on symbiotic nitrogen fixation : legume/Rhizobium.. [Food and Agriculture Organization of the United Nations ... http://id.worldcat.org/fast/1038049> # Nitrogen--Fixation. a schema:Intangible ;. schema:name "Nitrogen--Fixation"@en ;. .. ... http://id.loc.gov/authorities/subjects/sh85092063> # Nitrogen--Fixation. a schema:Intangible ;. schema:name "Nitrogen--Fixation ... schema:name "Technical handbook on symbiotic nitrogen fixation : legume/Rhizobium."@en ;. schema:productID "32971292" ;. schema ...
... with C3-symmetric ligands catalyze nitrogen fixation. Photolytic nitrogen splitting is also considered. Although nitrogen ... Abiological nitrogen fixation describes chemical processes that fix (react with) N2, usually with the goal of generating ... An early influential discovery of abiological nitrogen fixation was made by Volpin and co-workers in Russia. Aspects are ... The dominant technology for abiological nitrogen fixation is the Haber process, which uses an iron-based heterogeneous ...
Dinitrogen fixation by plants is a major source of new nitrogen to land ecosystems. Climatic constraints on the nitrogen cycle ... A long-standing puzzle2 is that trees capable of nitrogen fixation are abundant in nitrogen-rich tropical forests, but absent ... In contrast, sustained nitrogen deficits following disturbance in extra-tropical forests favour an obligate fixation strategy, ... This biome-scale pattern presents an evolutionary paradox3, given that the physiological cost4 of nitrogen fixation predicts ...
Nitrogen fixation is a biological process whereby atmospheric nitrogen (N2), which is chemically rather inert, is converted ... The product of the Klebsiella pneumoniae nifX gene is a negative regulator of the nitrogen fixation (nif) regulon. J. Bacteriol ... "Nitrogen Fixation. Electrons flow from ferredoxin to the reductase (iron protein, or Fe protein) to nitrogenase (molybdenum- ... Schmitz RA, Klopprogge K, Grabbe R. Regulation of nitrogen fixation in Klebsiella pneumoniae and Azotobacter vinelandii: NifL, ...
This is called biological nitrogen fixation.. Types of nitrogen fixation. In addition to biological fixation that takes place ... Symbiotic nitrogen fixation. One of the most interesting forms of biological nitrogen fixation is that which takes place by ... Importance of nitrogen fixation to crops. The microorganisms ability to fix atmospheric nitrogen is often discussed in terms ... The form of nitrogen produced is the same form of nitrogen that is found in several types of commercial nitrogen fertilizers. ...
Biological nitrogen fixation: rates, patterns and ecological controls in terrestrial ecosystems.. Vitousek PM1, Menge DN, Reed ... Biological nitrogen fixation: rates, patterns and ecological controls in terrestrial ecosystems. Philos Trans R Soc Lond B Biol ... New techniques have identified a wide range of organisms with the capacity to carry out biological nitrogen fixation (BNF)- ... Box diagram for the calculation of terrestrial biological nitrogen fixation (BNF) by difference; values in parentheses are ...
... brainmass.com/biology/photosynthesis/nitrogen-fixation-nodulation-capacities-14224 Solution Preview. For better comparison of ...
The Rhizobium growing in nodules on the roots of leguminous plants fix atmospheric nitrogen (... ... Carolina® Nitrogen-Fixation Study Kit (with perishables). Item # 154743P Online Only *bvseo_sdk, java_sdk, bvseo-4.0.0 ... The Rhizobium growing in nodules on the roots of leguminous plants fix atmospheric nitrogen (N2). This supplies plants with ... The Rhizobium growing in nodules on the roots of leguminous plants fix atmospheric nitrogen (N2). This supplies plants with ...
Nitrogen fixation requires a great deal of energy and so the genes that carry out nitrogen fixation (so called nif genes) are ... "Normally the genes for nitrogen fixation are locked off and only unlocked and used when nitrogen levels in the environment fall ... "Bacteria that fix nitrogen only do so when they sense that there is very little nitrogen available in their environment," says ... The result is that, when conditions are right for nitrogen fixation, NifA is released from the grip of NifL and is then able to ...
African Association for nitrogen fixation) is a non-government multidisciplinary group based since 1982, including experts in ... African Association for Biological Nitrogen Fixation -AABNF. AABNF (African Association for nitrogen fixation) is a non- ... Biological Nitrogen Fixation and agricultural development in Africa, great importance was given to field applications. BNF and ... teaching and the use of biological nitrogen fixation systems to increase food production and reduce malnutrition in Africa. ...
14th European Nitrogen Fixation Conference 2020. The 14th European Nitrogen Fixation Conference (ENFC), will be held 27-30 ... The ENFC is a European based biennial congress that brings together scientists investigating biological N2 fixation (BNF) from ... regulation of N2 fixation in soil and aquatic free-living microorganisms) with highly relevant and timely topics for modern ...
Article #3: Nitrogen Fixation by John Tobe. Here is how nature provides nitrogen for plants in the soil. ... This act of conversion is what is known as nitrogen fixation and by this means nature provides simple nitrogen to the earth for ... The way scientists would describe nitrogen fixation is as follows: "Gaseous nitrogen diffusing into the soil from the air is ... Nitrogen Fixation. Support our website, and your well being, by purchasing our 2380 pages megabook. Raw Food Explained: Life ...
... a comprehensive and detailed source of information on the genetic and regulatory aspects of biological nitrogen fixation in ... Genetics and regulation of nitrogen fixation in free-living bacteria. [Werner Klipp;] -- This book provides ... fixation_genetics> # Nitrogen Fixation--genetics a schema:Intangible ;. schema:name "Nitrogen Fixation--genetics"@en ;. . ... fixation> # Nitrogen--Fixation a schema:Intangible ;. schema:name "Nitrogen--Fixation"@en ;. . ...
Section 18 Nitrogen Fixation and Cereals. Chapter 108. The Quest for Biological Nitrogen Fixation in Cereals : A Perspective ... as well as nitrogen fixation and cereals.. Covering the full breadth of current nitrogen fixation research and expanding it ... Biological nitrogen fixation is an alternative to nitrogen fertilizer. It is carried out by prokaryotes using an enzyme complex ... One Hundred Years Discovery of Nitrogen-Fixing Rhizobacteria. Claudine Elmerich. Chapter 89. Symbiotic Nitrogen Fixation in ...
These processes, which influence the regulation of N2 fixation and are finely tuned on a whole-plant basis, are extensively ... Many processes operate and interact within the symbiotic relationship between plants and nodules, including nitrogen (N)/carbon ... and malate seems to play a crucial role in many aspects of symbiotic N2 fixation control. How legumes specifically sense N- ... status and how this stimulates all of the regulatory factors are key issues for understanding N2 fixation regulation on a whole ...
  • The final, nitrogenous product of biological nitrogen fixation is ammonia . (everything2.com)
  • All biological nitrogen fixation is effected by enzymes called nitrogenases . (wikipedia.org)
  • Biological nitrogen fixation was discovered by German agronomist Hermann Hellriegel [10] and Dutch microbiologist Martinus Beijerinck . (wikipedia.org)
  • [11] Biological nitrogen fixation (BNF) occurs when atmospheric nitrogen is converted to ammonia by a nitrogenase enzyme. (wikipedia.org)
  • Biological nitrogen (N2) fixation, a microbiological process which converts atmospheric N2 into a plant-usable form, offers this alternative. (springer.com)
  • Biological dinitrogen fixation is manifested in vastly different patterns across the biosphere 8 . (nature.com)
  • Nitrogen fixation is a biological process whereby atmospheric nitrogen (N 2 ), which is chemically rather inert, is converted into biologically available forms ("fixed"), initially as ammonia. (rationalwiki.org)
  • This is called biological nitrogen fixation . (missouri.edu)
  • In addition to biological fixation that takes place by microorganisms in the soil, fixation can also take place chemically. (missouri.edu)
  • One of the most interesting forms of biological nitrogen fixation is that which takes place by microorganisms living in very small nodules on the roots of certain plants such as legumes. (missouri.edu)
  • Biological nitrogen fixation: rates, patterns and ecological controls in terrestrial ecosystems. (nih.gov)
  • New techniques have identified a wide range of organisms with the capacity to carry out biological nitrogen fixation (BNF)-greatly expanding our appreciation of the diversity and ubiquity of N fixers-but our understanding of the rates and controls of BNF at ecosystem and global scales has not advanced at the same pace. (nih.gov)
  • Biological nitrogen fixation or diazotrophy is an important microbially mediated process that converts dinitrogen (N2) gas to ammonia (NH3) using the nitrogenase protein complex (Nif). (wikipedia.org)
  • All biological reactions involving the process of nitrogen fixation are catalysed by enzymes called nitrogenases. (wikipedia.org)
  • Biological nitrogen fixation was discovered by Jean-Baptiste Boussingault in 1838. (wikipedia.org)
  • AABNF (African Association for nitrogen fixation) is a non-government multidisciplinary group based since 1982, including experts in soil science, nutrition, agronomy, microbiology, politicians and other interested promoting research, teaching and the use of biological nitrogen fixation systems to increase food production and reduce malnutrition in Africa. (omicsonline.org)
  • Congresses are held regularly to share experience and information in order to assess progress and plan for effective exploitation of biological nitrogen fixation systems in Africa. (omicsonline.org)
  • Biological Nitrogen Fixation and agricultural development in Africa, great importance was given to field applications. (omicsonline.org)
  • The ENFC is a European based biennial congress that brings together scientists investigating biological N2 fixation (BNF) from different prospects (e.g. biochemistry, microbiology, ecology, plant physiology, etc. (fems-microbiology.org)
  • This book provides a comprehensive and detailed source of information on the genetic and regulatory aspects of biological nitrogen fixation in free-living (non-symbiotic) prokaryotes. (worldcat.org)
  • Biological nitrogen fixation is represented in a diverse range of microorganisms, among which Klebsiella pneumoniae serves as a paradigm for the genetic analysis of diazotrophy, which is the ability to grow with N as sole nitrogen source. (worldcat.org)
  • Biological nitrogen fixation is an alternative to nitrogen fertilizer. (wiley.com)
  • Biological Nitrogen Fixation is a comprehensive two volume work bringing together both review and original research articles on key topics in nitrogen fixation. (wiley.com)
  • Chapters across both volumes emphasize molecular techniques and advanced biochemical analysis approaches applicable to various aspects of biological nitrogen fixation. (wiley.com)
  • Covering the full breadth of current nitrogen fixation research and expanding it towards future advances in the field, Biological Nitrogen Fixation will be a one-stop reference for microbial ecologists and environmental microbiologists as well as plant and agricultural researchers working on crop sustainability. (wiley.com)
  • Biological nitrogen fixation (BNF) has become important in rice farming systems because this process diminishes the need for expensive chemical fertilizers which have been associated with numerous health and environmental problems. (bookdepository.com)
  • Biological nitrogen fixation is catalyzed by nitrogenase, a complex metalloenzyme found only in prokaryotes. (asm.org)
  • N2Africa is a large scale, development to research project focused on increasing inputs from biological nitrogen fixation (BNF) by grain and fodder legumes among smallholders in sub-Saharan Africa. (wur.nl)
  • A team of researchers from NAI's Montana State University Team has proposed a new path in the evolution of biological nitrogen fixation on Earth. (astrobiology.com)
  • A key step in the global cycling of nitrogen is biological nitrogen fixation, which is accomplished via a protein known as 'nitrogenase. (astrobiology.com)
  • The process carried out by these microbes is known as biological nitrogen fixation. (jic.ac.uk)
  • Certain endophytic bacteria can provide nitrogen to the plants through biological nitrogen fixation, which is an important source of nitrogen input in agriculture and represents a promising substitute for chemical fertilizers, and are known as endophytic diazotrophic bacteria. (intechopen.com)
  • Research on endophytic diazotrophic bacteria has come a long way, and in this chapter, we have briefly discussed the mechanisms of biological nitrogen fixation and methods to quantify the fixed nitrogen along with reviewing recent studies focused on evaluating the role of endophytic diazotrophic bacteria in promoting plant growth in both native and nonnative crop hosts. (intechopen.com)
  • The fundamental requirement for fixed forms of nitrogen for life on Earth, both at present and in the past, has led to broad and significant interest in the origin and evolution of biological N 2 fixation. (frontiersin.org)
  • Insights gained from such studies, as reviewed herein, challenge traditional models for the evolution of biological nitrogen fixation and provide the basis for the development of new conceptual models that explain the stepwise evolution of this highly complex life sustaining process. (frontiersin.org)
  • Legumes have a unique biological process called nitrogen fixation (NF) by which they convert atmospheric nitrogen to ammonia. (frontiersin.org)
  • Biological nitrogen fixation is a worldwide economical and sustainable alternative for nitrogen supply to legume crops. (scielo.br)
  • Unfortunately, biological nitrogen fixation in common bean field crops has exhibited unstable behavior (Mostasso et al. (scielo.br)
  • Several approaches have been used to obtain new rhizobia strains which exhibit better biological nitrogen fixation responses on common bean. (scielo.br)
  • Cusack DF, Silver W, McDowell WH (2009b) Biological nitrogen fixation in two tropical forests: ecosystem-level patterns and effects of nitrogen fertilization. (upenn.edu)
  • Although rarely measured, tropical forests likely maintain considerable biological N fixation (BNF) to balance N losses. (upenn.edu)
  • Biological nitrogen fixation can have a role in this if it can be applied to the major food crop plants. (intechopen.com)
  • This led to speculation that the crop was benefiting from biological nitrogen fixation (BNF). (intechopen.com)
  • The authors isolated samples of the microbial community from each cultivation type, inoculated test plants growing under common conditions, and observed the effects on biomass, number and size of nitrogen-fixing nodules, chlorophyll content, and estimated rates of biological nitrogen fixation. (lternet.edu)
  • If so, the inoculation of common bean with efficient rhizobial strains may be the mean to improve biological nitrogen fixation and common bean productivity. (europa.eu)
  • The effect of drought (D) on biological nitrogen fixation (BNF) has been widely reported (for review, see Zahran, 1999 ) and is considered to be by far the most important environmental factor resulting in crop yield loss ( Boyer, 1982 ). (plantphysiol.org)
  • Biological N2 fixation (BNF) in the rhizosphere of Podocarpaceae is currently attributed to unspecific diazotrophs with negligible impact on N acquisition. (uni-bayreuth.de)
  • Dr. Mohapatra emphasized that a practicable technology of utilizing the biological nitrogen fixation would be helpful in managing the environmental pollution on account of reduced losses of excess fertilizer N in the soil. (org.in)
  • DG suggested to achieve the long term objectives of this challenge programme on genetic engineering of rhizobia, rice endophytes and improving biological nitrogen fixation. (org.in)
  • Professor Ray Dixon, FRS, John Innes Centre, Norwich dwelt on the current scenario in biological nitrogen fixation and the future prospects of developing nitrogen fixing cereals and making rice more dependent on nitrogen fixation and reduce the chemical N fertilizer requirement as well as the steps required to achieve progress in such a challenging area. (org.in)
  • Some studies also suggest that increasing application rate of biochar has a positive feedback on biological nitrogen fixation (BNF) and on soil microbial biomass. (helsinki.fi)
  • Belnap J (2001) Factors influencing nitrogen fixation and nitrogen release in biological soil crusts. (springer.com)
  • Biological nitrogen fixation is not only essential for world nitrogen balance but it is also an alternative to expensive commercial fertilizer for crop production. (umsystem.edu)
  • Bliss FA (1993) Breeding common bean for improved biological nitrogen fixation. (springer.com)
  • Dinh HT, Kaewpradit W, Jogoly S, Vorasoot N, Patanothai A (2013) Biological nitrogen fixation of peanut genotypes with different levels of drought tolerance under mid-season. (springer.com)
  • As I know Nitrogen-based fertilizers are requiered because Nitrogen fixation from air is to energy consuming.At least with presently existing biological catalysts. (thescienceforum.com)
  • Nitrogen fixation is the process by which atmospheric nitrogen gas is converted into ammonia. (reed.edu)
  • Abundant in nature (78% of the air we breathe), nitrogen is rarely used in the industrial production of chemicals, with the most important process being the synthesis of ammonia, which is in turn used for the preparation of agricultural fertilizers. (eurekalert.org)
  • N 2 ) is split into two atoms of nitrogen that can then be connected to other elements like hydrogen or carbon, which allow nitrogen to be stored as ammonia or converted directly in higher value compounds. (eurekalert.org)
  • In 2017, the lab of Marinella Mazzanti at EPFL was able to convert molecular nitrogen into ammonia in ambient conditions by synthesizing a compound containing two uranium(III) ions and three potassium centers held together by a nitride group. (eurekalert.org)
  • We applied this approach to an agriculturally relevant gene cluster from Klebsiella oxytoca encoding the nitrogen fixation pathway for converting atmospheric N 2 to ammonia. (pnas.org)
  • Electrons flow from ferredoxin to the reductase (iron protein, or Fe protein) to nitrogenase (molybdenum-iron protein, or MoFe protein) to reduce nitrogen to ammonia. (rationalwiki.org)
  • An example of this is in the fertilizer industry where atmospheric nitrogen (N 2 ) can be combined with hydrogen (H + ) to make anhydrous ammonia (NH 3 ) and other nitrogen fertilizer products. (missouri.edu)
  • Nitrogen fixation is a chemical process by which molecular nitrogen (N 2) in the air is converted into ammonia (NH 3) or related nitrogenous compounds in soil or aquatic systems. (wikipedia.org)
  • The protein complex nitrogenase is responsible for catalyzing the reduction of nitrogen gas (N2) to ammonia (NH3). (wikipedia.org)
  • The production of the nitrogenase complex is genetically regulated, and the activity of the protein complex is dependent on ambient oxygen concentrations, and intra- and extracellular concentrations of ammonia and oxidized nitrogen species (nitrate and nitrite). (wikipedia.org)
  • It is carried out by prokaryotes using an enzyme complex called nitrogenase and results in atmospheric N2 being reduced into a form of nitrogen diazotrophic organisms and plants are able to use (ammonia). (wiley.com)
  • Abiological nitrogen fixation describes chemical processes that fix (react with) N2, usually with the goal of generating ammonia. (wikipedia.org)
  • Nitrogenase, which catalyzes the ATP-dependent reduction of dinitrogen (N 2 ) to ammonia (NH 3 ), accounts for roughly half of the bioavailable nitrogen supporting extant life. (frontiersin.org)
  • Legumes perform a special symbiotic process called nitrogen fixation (NF) that can fix atmospheric nitrogen (N 2 ) to ammonia (NH 3 ) by rhizobium. (frontiersin.org)
  • Nitrogen fixation is a chemical process that converts atmospheric nitrogen into ammonia, which is absorbed by organisms. (maximumyield.com)
  • Atmospheric nitrogen is plentiful, making up approximately 78% of the earth's atmosphere, but it's also inert, so it needs to be converted into another form, such as ammonia, that is more easily absorbed by plants. (maximumyield.com)
  • They thrive in a low oxygen atmosphere where they fix or feed on nitrogen, converting it into ammonia as a byproduct. (maximumyield.com)
  • We explore quantitative assessments of these strategies to study the prokaryotic trait of nitrogen fixation, the enzyme-catalyzed reduction of N 2 to ammonia. (pnas.org)
  • All organisms depend on utilizable nitrogen, but only a few prokaryotes can obtain it from atmospheric nitrogen (N 2 ) through conversion of N 2 to ammonia, catalyzed by the heterodimeric enzyme nitrogenase. (pnas.org)
  • Nitrogen fixation is where nitrogen (N2) in the atmosphere is converted into ammonia (NH3). (nanowerk.com)
  • Plants with symbiotic bacteria (like Leguminosae http://www.biolib.cz/en/taxon/id3273/ ) can convert nitrogen to ammonia. (biology-online.org)
  • These bacteria can take nitrogen gas from the air in the soil and transform it into ammonia (NH 3 ) that converts to ammonium (NH 4 ) which can be used by the plant. (tamu.edu)
  • Fixation of nitrogen even with liberation of energy or free energy, will take place if either oxygen gas or hydrogen gas, or other substances, especially gases, whose standard free energies are close to zero, are involved to form either nitrates, ammonia, or cyanide, not to speak of still other compounds. (rupress.org)
  • Nitrogen fixation is the conversion of dinitrogen gas (N2) to ammonia (NH3) and can be catalyzed by biotic and abiotic processes. (ufl.edu)
  • Cyanobacteria inhabit nearly all illuminated environments on Earth and play key roles in the carbon and nitrogen cycle of the biosphere . (wikipedia.org)
  • In general, cyanobacteria can use various inorganic and organic sources of combined nitrogen, such as nitrate , nitrite , ammonium , urea , or some amino acids . (wikipedia.org)
  • Well-characterized nitrogen-fixing systems have been found in some free-living species of cyanobacteria (e.g. (rationalwiki.org)
  • Volume 2 covers the symbiotic interaction of nitrogen fixing organisms with their host plants, including nodulation and symbiotic nitrogen fixation, plant and microbial "omics", cyanobacteria, diazotrophs and non-legumes, field studies and inoculum preparation, as well as nitrogen fixation and cereals. (wiley.com)
  • Marine nitrogen-fixing cyanobacteria are largely confined to the tropical and subtropical ocean. (rug.nl)
  • Together, these results point at a lower temperature limit for unicellular nitrogen-fixing cyanobacteria, which offers an explanation for their (sub) tropical distribution and suggests expansion of their biogeographical range by global warming. (rug.nl)
  • The importance of energy supply for fixation can be seen by comparing these rates to those found in legumes, where the symbiotic bacteria are supplied with high-energy products from photosynthesis. (encyclopedia.com)
  • In nature, nitrogen is most commonly fixed by certain types of soil-dwelling bacteria . (everything2.com)
  • Lightning also fixes nitrogen directly in the atmosphere , though at a much smaller total rate than that of bacteria. (everything2.com)
  • Nitrogen fixation is carried out naturally in soil by microorganisms termed diazotrophs that include bacteria such as Azotobacter and archaea . (wikipedia.org)
  • Some nitrogen-fixing bacteria have symbiotic relationships with plant groups, especially legumes . (wikipedia.org)
  • Several obligately anaerobic bacteria fix nitrogen including many (but not all) Clostridium spp. (wikipedia.org)
  • The tree, sacred in Mayanmythology, was considered the tree of life, connecting heaven and Earth.Studies conducted in the monument determined that the trace elementmolybdenum limits the activity of nitrogen-fixing bacteria that live insoils where the tree is found. (acs.org)
  • Nitrogen-fixing bacteria belonging to genera such as Rhizobium , Bradyrhizobium , etc. are commonly found in root nodules on plants (mostly legumes), and some crops are grown only because of the high levels of nitrogen compounds produced in the roots. (rationalwiki.org)
  • Bacteria that fix nitrogen only do so when they sense that there is very little nitrogen available in their environment," says Professor Ray Dixon (Project Leader at the JIC. (innovations-report.com)
  • The discovery of the role of nitrogen fixing bacteria by Herman Hellriegel and Herman Wilfarth in 1886-8 would open a new era of soil science. (wikipedia.org)
  • Bacteria through fixation enrich wood substrate with nitrogen thus enabling deadwood decomposition by fungi. (wikipedia.org)
  • Here the bacteria obtains carbonaceous food from the plant and carries on the nitrogen fixation process, storing up the resulting nitrogeneous food material. (rawfoodexplained.com)
  • One of the major factors that limit crop growth is the availability of nitrogen, but only bacteria and other single-celled microbes called archaea can take nitrogen from the air and fix it into a form that can be used by plants. (jic.ac.uk)
  • Legumes obtain nitrogen from symbiotic nitrogen-fixing bacteria, but cereal crops including wheat and maize, rely on the availability of fixed nitrogen in the soil. (jic.ac.uk)
  • Besides fixing nitrogen, endophytic bacteria can produce plant growth hormones like auxin and gibberellin, help in nutrient uptake, and increase the plant's tolerance to biotic and abiotic stresses. (intechopen.com)
  • Various direct and indirect methods have been used to quantify the amount of nitrogen fixed by these bacteria, including the acetylene reduction assay, which is a quick but indirect method, and the 15N isotopic dilution assay, which is a robust and accurate method. (intechopen.com)
  • Diazortrophs are a form of a bacteria and archaea organism that grow without external forms of nitrogen, which means they are able to utilize only the nitrogen that is present in the atmosphere itself. (maximumyield.com)
  • I think its that denitrifing bacteria in the soil convert the excess nitrates into nitrites and then nitrogen gas so that the nitrogen can be put back into the cycle. (biology-online.org)
  • In reality it is not the plant that removes nitrogen from the air but Rhizobium bacteria which live in small tumor like structures called nodules on the legume plant roots. (tamu.edu)
  • The nitrogen fixation (N 2 -fixation) process between the legume plant and rhizobia bacteria is referred to as a symbiotic (mutually beneficial) relationship. (tamu.edu)
  • Rhizobia bacteria provide the legume plant with nitrogen in the form of ammonium and the legume plant provides the bacteria with carbohydrates as an energy source. (tamu.edu)
  • Different concentrations of Mo and Co were found to induce high root nodules, nitrogenase activity and nitrogen fixing bacteria. (scialert.net)
  • The photosynthetic bacteria, in particular members of the Rhodospirillaceae, are attractive organisms for genetic and biochemical analyses of nitrogen fixation. (umsystem.edu)
  • [1] Atmospheric nitrogen is molecular dinitrogen , a relatively nonreactive molecule that is metabolically useless to all but a few microorganisms. (wikipedia.org)
  • Certain microorganisms found in the soil are able to convert atmospheric nitrogen into forms plants can use. (missouri.edu)
  • The microorganism's ability to fix atmospheric nitrogen is often discussed in terms of the plant's ability to fix nitrogen. (missouri.edu)
  • The bacterium Azotobacter vinelandii is able to fix atmospheric nitrogen when available nitrogen in its environment falls below a threshold level. (innovations-report.com)
  • In 1901 Beijerinck showed that azotobacter chroococcum was able to fix atmospheric nitrogen. (wikipedia.org)
  • Atmospheric nitrogen is inaccessible to most organisms. (wikipedia.org)
  • Nitrogen is abundant on our planet as an atmospheric gas. (astrobiology.com)
  • Nitrogen fixation is essentially converting atmospheric nitrogen into a form that plants can more readily utilize. (maximumyield.com)
  • Atmospheric nitrogen is converted by the action of diazotrophs. (maximumyield.com)
  • Fixed nitrogen (N) is a limiting algal nutrient in the low latitude ocean, and the oceanic N inventory has been suggested to increase during ice ages so as to lower atmospheric CO_2. (caltech.edu)
  • Some free-living organisms fix enough N 2 in vitro to grow without added nitrogen, but limited energy supply can limit N 2 fixation in nature. (encyclopedia.com)
  • For instance, non-symbiotic organisms in primary successional areas of the Hawaii Volcanoes National Park were found to fix only 0.3 to 2.8 kilograms of N 2 per hectare per year, and non-symbiotic N 2 fixation in soil rarely exceeds 15 kilograms per hectare per year. (encyclopedia.com)
  • Although nitrogen is a critical element in both terrestrial and aquatic productivity, and nitrogen fixation is a key process that balances losses due to denitrification in both environments, most resources on the subject focuses on the biochemistry and microbiology of such processes and the organisms involved in the terrestrial environment on symbiosis in terrestrial systems, or on largely ecological aspects in the marine environment. (springer.com)
  • Many nitrogen-fixing organisms exist only in anaerobic conditions, respiring to draw down oxygen levels, or binding the oxygen with a protein such as leghemoglobin . (wikipedia.org)
  • Living organisms capable of fixing nitrogen are known as diazotrophs. (rationalwiki.org)
  • Volume 1 explores the chemistry and biochemistry of nitrogenases, nif gene regulation, the taxonomy, evolution, and genomics of nitrogen fixing organisms, as well as their physiology and metabolism. (wiley.com)
  • Nitrogenase: enzymes used by organisms to fix nitrogen Transition metal dinitrogen complex Metal nitrido complex Chalkley, Matthew J. (wikipedia.org)
  • Thus, engineering nitrogen fixation activity in photosynthetic organisms that produce oxygen is challenging. (asm.org)
  • Conceptual translation of the hnifU cDNA yielded a protein product bearing 77% and 70% amino acid identity to NifU-like hypothetical proteins from Haemophilus influenzae and Saccharomyces cerevisiae, respectively, and 40-44% identity to the N-terminal regions of NifU proteins from several diazatrophs (i.e., nitrogen-fixing organisms). (nih.gov)
  • Further, the NifU-like proteins of non-nitrogen-fixing organisms were similar only to the N-terminal region of diazatrophic NifU proteins and therefore identified a novel modular domain in these NifU proteins. (nih.gov)
  • The process has been exhaustively studied biochemically, and, in certain environments, organisms able to fix nitrogen have a strong selective advantage. (pnas.org)
  • With nitrogen fixation being a process highly sensitive to oxygen species we propose that the BMAA effects found here may be related to the production of reactive oxygen species, as reported for other organisms. (mdpi.com)
  • Because nitrogen fixing organisms employ different strategies regarding their activity, it is assumed that different types of microbial mats also exhibit different daily patterns of nitrogen fixation. (uva.nl)
  • Mo is involved in regulating expression of the nitrogen fixation ( nif ) genes in a number of organisms. (brillonline.com)
  • Iron (Fe) is an essential micronutrient for symbiotic nitrogen fixation in legume nodules, where it is required for the activity of bacterial nitrogenase, plant leghemoglobin, respiratory oxidases, and other Fe proteins in both organisms. (plantphysiol.org)
  • If nitrogen fixation is exothermic and free energy-yielding, how is the carbohydrate requirement of nitrogen-fixing organisms to be interpreted? (rupress.org)
  • His research has focused on nitrogen cycling by aquatic microorganisms, although he has publications spanning topics in microbial diversity in freshwater and hypersaline systems, organic matter metabolism, selenium metabolism in estuarine sediments, and nitrogen metabolism in oligotrophic oceans. (springer.com)
  • Anderson A J and Spencer D 1950a Molybdenum in nitrogen metabolism of legumes and non-legumes. (springer.com)
  • However, engineering diazotrophic plants, however attractive a proposition, is an extreme challenge, due to the complexities in the biosynthesis of active nitrogenase, the enzyme that catalyzes nitrogen fixation, and the difficulty of coupling plant metabolism to supply energy and reducing power for the nitrogen fixation process ( 4 ). (asm.org)
  • The research was carried out as part of the NAI project "Evolution of Nitrogen Fixation, Photosynthesis, Hydrogen Metabolism, and Methanogenesis. (astrobiology.com)
  • Figure 15.06 Nitrogen metabolism in context. (powershow.com)
  • Is further hope given to those who may experimentally try to narrow this ratio to where the carbon used is only for the carbon requirements of general metabolism, exclusive of fixation? (rupress.org)
  • Does it not indicate that perhaps the function of fixation is often to obtain energy for use in general metabolism? (rupress.org)
  • Is the general carbohydrate metabolism of the fixation forms to be regarded as being merely extremely inefficient? (rupress.org)
  • This article emphasizes symbiotic N 2 fixation in grain and pasture legumes in the family Fabaceae. (encyclopedia.com)
  • Rates of symbiotic N 2 fixation in legumes vary with plant species and cultivar, growing season , and soil fertility. (encyclopedia.com)
  • Inclusion of legumes in crop rotations is generally thought to improve soil nitrogen levels, but benefits depend on the level of N 2 fixed and the amount of nitrogen removed in grain or forage. (encyclopedia.com)
  • Andrew, C S 1976 Effect of calcium, pH and nitrogen on the growth and chemical composition of some tropical and temperate pasture legumes. (springer.com)
  • Andrew C S 1977b The effect of sulphur on the growth, sulphur and nitrogen concentrations, and critical sulphur concentrations of some tropical and temperate pasture legumes. (springer.com)
  • Barron, A. R., Purves, D. W. & Hedin, L. O. Facultative nitrogen fixation by canopy legumes in a lowland tropical forest. (nature.com)
  • One of the most common groups of plants that fix nitrogen are legumes. (missouri.edu)
  • Of the total nitrogen required by legumes, generally about half is nitrogen fixed from the atmosphere, with the remainder being taken up from residual nitrate in the soil. (missouri.edu)
  • This means that where legumes are grown, outside applications of manure or fertilizer nitrogen are not needed. (missouri.edu)
  • Different legumes also vary in the amount of total nitrogen they can fix. (missouri.edu)
  • Listed below in the table are common legumes used in agriculture and the total amounts of nitrogen they fix during a growing season. (missouri.edu)
  • The process of nitrogen fixation by legumes alone probably does not significantly impact water quality. (missouri.edu)
  • Therefore, not only is this plant able to secure the nitrogen it needs even when there is insufficient nitrogen in the soil … but these legumes actually add to that supply and as far as nitrogen is concerned, leaves the land more fertile than before they grew. (rawfoodexplained.com)
  • How legumes specifically sense N-status and how this stimulates all of the regulatory factors are key issues for understanding N 2 fixation regulation on a whole-plant basis. (mdpi.com)
  • Grain legumes are also a key source of nitrogen-rich edible seeds, providing a wide variety of high-protein products and constituting the major source of dietary protein in the diets of the poor in most parts of sub-Saharan Africa. (wur.nl)
  • A legume plant's ability to use nitrogen from the air is the best known benefit of growing legumes but the least understood. (tamu.edu)
  • The quantity of nitrogen fixed by legumes can range from almost none to over 200 lb/acre. (tamu.edu)
  • 1980. Symbiotic nitrogen fixation by legumes requires extra phosphorus. (hawaii.edu)
  • The microbial nif genes required for nitrogen fixation are widely distributed in diverse environments. (wikipedia.org)
  • Anf and Vnf systems are invariably found with Nif genes, and then only expressed under Mo limiting situations, producing less nitrogen-reducing activity than the Mo-dependent nitrogenase. (rationalwiki.org)
  • Normally the genes for nitrogen fixation are locked off and only unlocked and used when nitrogen levels in the environment fall. (innovations-report.com)
  • Nitrogen fixation requires a great deal of energy and so the genes that carry out nitrogen fixation (so called nif genes) are tightly regulated and switched off when not required. (innovations-report.com)
  • The result is that, when conditions are right for nitrogen fixation, NifA is released from the grip of NifL and is then able to stimulate the activity of the nif genes and so switches on nitrogen fixation by the cell. (innovations-report.com)
  • PCC 6803 through the transfer of 35 nitrogen fixation ( nif ) genes from the diazotrophic cyanobacterium Cyanothece sp. (asm.org)
  • The ability to introduce into crop plants the machinery to fix their own nitrogen via direct transfer of nitrogen fixation ( nif ) genes is envisioned to be key for the next agricultural revolution ( 1 - 3 ). (asm.org)
  • To date, the heterotrophic bacterium Escherichia coli has been successfully engineered for nitrogen fixation activity through transfer of nif genes from various diazotrophic species ( 13 - 17 ). (asm.org)
  • In this paper, the research team has been able to engineer nitrogen fixation by employing a novel strategy, which simplifies the process of engineering multiple genes to make sure their expression is balanced in their new host. (jic.ac.uk)
  • Nitrogen fixation (nif) genes of the cyanobacterium Anabaena species strain PCC 7120. (wikigenes.org)
  • Bacterial-type ferredoxin genes in the nitrogen fixation regions of the cyanobacterium Anabaena sp. (wikigenes.org)
  • hnifU, a gene exhibiting similarity to nifU genes of nitrogen fixation gene clusters, was identified in the course of expressed sequence tag (EST) generation from a human fetal heart cDNA library. (nih.gov)
  • On hosts in which HR plasmids impair N fixation, the plasmids also enhance competitiveness for nodule occupancy, showing that naturally occurring, transferrable accessory genes can convert beneficial rhizobia to a more exploitative lifestyle. (apsnet.org)
  • Phylogenies constructed on nitrogen fixation genes are not in agreement with the tree-of-life based on 16S rRNA but do not conclusively distinguish between gene loss and LGT hypotheses. (pnas.org)
  • Rhizobia produce stem or root nodules on their host(s), and within these nodules receive protection from external stresses and energy for growth and N 2 fixation. (encyclopedia.com)
  • In most legume nodules, the di-nitrogen (N 2 )-fixing rhizobia are present as organelle-like structures inside their root host cells. (mdpi.com)
  • This study aimed to genetically characterize four new Rhizobium strains, and to evaluate their nodulation and fixation capacity compared to commercial strains and to native rhizobia population of a Brazilian Rhodic Hapludox. (scielo.br)
  • To take advantage of common bean ( Phaseolus vulgaris L.) nitrogen biofertilizer, several studies have sought to identify efficient and competitive strains of rhizobia to cope the nitrogen requirements of this important crop. (scielo.br)
  • Every method used for demonstrating nitrogen fixation in rhizobia have been used to demonstrate nitrogen fixation in G. diazotrophicus both in vitro and in planta, and field trials demonstrate yield increases and the potential to reduce nitrogen fertilizer use, meeting both food security and climate smart agriculture needs. (intechopen.com)
  • Low-oxygen concentration in infected nodule cells contributes to the differentiation of rhizobia into nitrogen-fixing bacteroids and enables prolonged activity of oxygen-labile nitrogenase ( Hennecke, 1990 ). (plantphysiol.org)
  • Factors that influence the quantity of nitrogen fixed are the level of soil nitrogen, the rhizobia strain infecting the legume, amount of legume plant growth, how the legume is managed, and length of growing season. (tamu.edu)
  • Most legume species have a specific rhizobia strain that maximizes N 2 -fixation. (tamu.edu)
  • Some of these rhizobia strains are capable of infecting a given legume species but will vary in their efficiency to fix nitrogen. (tamu.edu)
  • Effective rhizobia strains that fix high rates of nitrogen form fewer but larger nodules that have dark pink centers. (tamu.edu)
  • Sustainability considerations mandate that alternatives to chemical nitrogen fertilizers must be urgently sought. (springer.com)
  • The form of nitrogen produced is the same form of nitrogen that is found in several types of commercial nitrogen fertilizers. (missouri.edu)
  • To compensate , modern agriculture has been highly reliant on industrial nitrogen fertilizers to achieve maximum crop productivity. (wiley.com)
  • IMPORTANCE Application of chemically synthesized nitrogen fertilizers has revolutionized agriculture. (asm.org)
  • It may reduce the expenses with chemical nitrogen fertilizers, as well as eliminating the negative impact of them on the environment (Straliotto et al. (scielo.br)
  • There is a need to reduce the negative polluting influence of mineral nitrogen fertilizers and to develop a more sustainable climate smart agriculture capable of meeting our future food security needs. (intechopen.com)
  • For many years, and in deed for decades, Brazilian sugarcane had been produced in the same regions with little use of nitrogen fertilizers, without any apparent loss in yield [ 1 ]. (intechopen.com)
  • Subsequent to this, studies confirmed that some varieties of Brazilian sugarcane were capable of obtaining 60-80% of their nitrogen requirements from BNF, highlighting the possibility that under the right conditions, it might be possible to dispense altogether with nitrogen fertilizers for these varieties [ 1 , 3 ]. (intechopen.com)
  • The outputs of the project in the form of improved rhizobial strains for pigeonpea, improved understanding of how to enhance the ability of rice to obtain N from fixation, strong capacity building to train the next generation of researches is expected to give strong support to programmes for enhancing BNF and saving chemical fertilizers. (org.in)
  • Breeding for high symbiotic nitrogen (N) fixation (SNF) in common bean ( Phaseolus vulgaris L.) is expected to contribute to reduced application of chemical fertilizers in cropping systems involving common bean. (springer.com)
  • Our data show that exogenously applied BMAA rapidly inhibits nitrogenase activity (acetylene reduction assay), even at micromolar concentrations, and that the inhibition was considerably more severe than that induced by combined nitrogen sources and most other amino acids. (mdpi.com)
  • As predicted by the second hypothesis, the respiratory cost of nitrogen fixation and also the cellular C:N ratio rose sharply at temperatures below 21 degrees C. In addition, we found that low temperature caused a strong delay in the onset of the nocturnal nitrogenase activity, which shortened the remaining nighttime available for nitrogen fixation. (rug.nl)
  • Many processes operate and interact within the symbiotic relationship between plants and nodules, including nitrogen (N)/carbon (C) metabolisms, oxygen flow through nodules, oxidative stress, and phosphorous (P) levels. (mdpi.com)
  • The carbonic anhydrase (CA)-phosphoenolpyruvate carboxylase (PEPC)-malate dehydrogenase (MDH) is a key pathway inside nodules involved in this regulation, and malate seems to play a crucial role in many aspects of symbiotic N 2 fixation control. (mdpi.com)
  • In this activity, students observe the colour inside the root nodules of clover (or other legume) to see if they are fixing nitrogen. (sciencelearn.org.nz)
  • An array of 2,304 cDNA clones derived from nitrogen-fixing nodules of Lotus japonicus was produced and used to detect differences in relative gene transcript abundance between nodules and uninfected roots. (apsnet.org)
  • nitrogen fixation by root nodules takes the nitrogen gas from the soil and converts it into ammonium compounds. (biology-online.org)
  • Ineffective strains will form many small nodules on the legume root but fix little or no nitrogen. (tamu.edu)
  • Technical handbook on symbiotic nitrogen fixation : legume/Rhizobium. (worldcat.org)
  • I thought you might be interested in this item at http://www.worldcat.org/oclc/32971292 Title: Technical handbook on symbiotic nitrogen fixation : legume/Rhizobium. (worldcat.org)
  • Agricultural practices-such as no-till, low-input, and organic cultivation-can change the ecology of the mutualism between soybean plants and their nitrogen-supplying rhizobium by altering bacterial communities, soil conditions, and plant behavior. (lternet.edu)
  • Legume-Rhizobium nitrogen fixation is dramatically affected under drought and other environmental constraints. (plantphysiol.org)
  • A rhizobium strain is the key ingredient in an inoculant that allows for nitrogen fixation. (producer.com)
  • The research team first began gathering different rhizobium strains, screening them in a lab setting to see how they would fix nitrogen. (producer.com)
  • In each test site two nitrogen supply management strategies, SNF-dependent and N fertilizer-dependent, were simulated separately in the field by inoculating the seed with a commercial Rhizobium leguminosarum bv. (springer.com)
  • For example decomposing wood which has generally low content of nitrogen was shown to host diazotrophic community. (wikipedia.org)
  • The requirements for ATP and reductant during diazotrophic growth, the physicochemical properties of the nitrogenase proteins, and the involvement of Mo in different aspects of N 2 fixation are reviewed. (brillonline.com)
  • Why is the energetically costly 4 strategy of dinitrogen fixation widespread if non-fixing neighbours can outcompete fixers in the nitrogen-rich conditions of tropical forests? (nature.com)
  • Conversely, why is dinitrogen fixation not widespread in extra-tropical forests, if fixers are competitively advantaged over non-fixers in nitrogen-poor soils? (nature.com)
  • Figure 1: Climate and biome differences in soil nitrogen deficit and evolutionary stable strategies (ESS) of dinitrogen fixation. (nature.com)
  • These mat types differ with regard to the daily patterns and daily integrated rates of dinitrogen fixation. (uva.nl)
  • Ladha JK, Peoples MB, Garrity DP, Capuno VT and Dart PJ (1993) Estimating dinitrogen fixation of hedgerow vegetation using the nitrogen-15 natural abundance method. (springer.com)
  • The atomic ratio of Carbon(C): Nitrogen(N): Phosphorus(P) observed on average in planktonic biomass was originally described by Alfred Redfield. (wikipedia.org)
  • 0.3 mu mol L-1), N-2 fixation rates were unaffected by iron and phosphorus amendments. (columbia.edu)
  • The mean TN/TP is 20 for surface-water sites with temperatures higher than 15°C, indicating that the average trophic conditions in the Baltic Proper are likely more limited by phosphorus than nitrogen. (diva-portal.org)
  • Nitrogen fixation is an important contributor to the nitrogen concentration and we give overall budgets for nitrogen and phosphorus in the Baltic Proper, including nutrient data from land uplift, which is the most important contributor for nutrients and often neglected in discussions about sources of nutrients to the Baltic Sea. (diva-portal.org)
  • Over the year long period of observation, N2 fixation varied with measured soluble reactive phosphorus (SRP) inventories and previously documented seasonality of iron (Fe) delivery to the North Pacific. (hawaii.edu)
  • We present results from a new Atlantic implementation of a coupled physical-biogeochemical model that includes an explicit, dynamic representation of N 2 -fixation with light, nitrogen, phosphorus and iron limitations, and variable stoichiometric ratios. (biogeosciences.net)
  • The model is able to reproduce nitrogen, phosphorus and iron concentration variability to first order. (biogeosciences.net)
  • Changes in the phosphorus remineralization rate (relative to nitrogen) linearly determine the surface nitrogen fixation rate because they change the degree of phosphorus limitation, which is the dominant limitation in the Atlantic in the model. (biogeosciences.net)
  • Phosphorus remineralization rate must be increased by about a factor of 2 (relative to nitrogen) in order to generate subsurface N* anomalies that are comparable to the observations. (biogeosciences.net)
  • Coles, V. J. and Hood, R. R.: Modeling the impact of iron and phosphorus limitations on nitrogen fixation in the Atlantic Ocean, Biogeosciences, 4, 455-479, https://doi.org/10.5194/bg-4-455-2007, 2007. (biogeosciences.net)
  • N 2 fixation is energetically highly expensive, and an energy-generating process such as photosynthesis can meet the energy demand of N 2 fixation. (asm.org)
  • Nitrogen (N) is an essential component of all proteins and enzymes, nucleic acids that make up DNA, and chlorophyll that enables the process of photosynthesis in plants [ 1 ]. (intechopen.com)
  • Nodule function requires more Mo than does the host plant, and in some symbioses nitrogen fixation may be specifically limited by low availability of Ca, Co, Cu and Fe. (springer.com)
  • Understanding how nodule N2 fixation responds to the environment is crucial for improving legume production and maintaining sustainability in the context of global change. (springer.com)
  • The program will combine classical topics within the BNF field (e.g. nitrogenase biochemistry, evolution of symbiosis, signal transduction, nodule development and functioning, regulation of N 2 fixation in soil and aquatic free-living microorganisms) with highly relevant and timely topics for modern society (e.g. climate change, environmental impact of BNF, present and future use of BNF in agriculture). (fems-microbiology.org)
  • However, it has yet to be established as to whether such regulation of nitrogen fixation is only exerted at the whole-plant level (e.g. by a systemic nitrogen feedback mechanism) or can also occur at a local nodule level. (plantphysiol.org)
  • Loss of MtMATE67 gene function resulted in accumulation of Fe in the apoplasm of nodule cells and a substantial decrease in symbiotic nitrogen fixation and plant growth. (plantphysiol.org)
  • Andrew C S, Kippo E A and Barford H 1952 Plant responses to nitrogen and sulphur on a heavy clay soil from the Darling Downs, South-east Queensland. (springer.com)
  • We conclude that biome-scale differences in the abundance of nitrogen fixers can be explained by the interaction between individual plant strategies and climatic constraints on the nitrogen cycle over evolutionary time. (nature.com)
  • In this case, microorganisms obtain food and energy from the root of the plant while producing nitrogen the plant can use for growth and development. (missouri.edu)
  • Experiments by Bossingault in 1855 and Pugh, Gilbert & Lawes in 1887 had shown that nitrogen did not enter the plant directly. (wikipedia.org)
  • These processes, which influence the regulation of N 2 fixation and are finely tuned on a whole-plant basis, are extensively reviewed in this paper. (mdpi.com)
  • N fixation, the process by which dinitrogen is reduced to plant-available forms, is, therefore, a vital process for the sustenance of life on earth. (intechopen.com)
  • Nitrogen is the most limiting nutrient for plant growth. (tamu.edu)
  • The rate of N 2 -fixation is directly related to legume plant growth rate. (tamu.edu)
  • Anything that reduces plant growth such as drought, low temperature, limited plant nutrients, or disease will also reduce N 2 -fixation. (tamu.edu)
  • If given a choice, a legume plant will remove nitrogen from the soil before obtaining nitrogen from the air through N 2 -fixation. (tamu.edu)
  • I want to use some of his ideas and plant nitrogen fixers next to each fruit tree. (permies.com)
  • The allure of nitrogen fixing cereals has enticed hundreds of plant scientists for more than a century. (producer.com)
  • It is also the first known diazotroph, the species that use diatomic nitrogen as a step in the complete nitrogen cycle. (wikipedia.org)
  • Here, we report an anodic replacement of the water oxidation reaction with more readily oxidizable species to facilitate ambient electrocatalytic nitrogen reduction reaction (NRR). (rsc.org)
  • We explored the potential utility of this species as a polyhydroxybutyrate production strain, correlating the effects of glucose, nitrogen availability, dissolved oxygen concentration, and extracellular pH with polyhydroxybutyrate production and changes in the Y88 proteomic profile. (nih.gov)
  • Nitrogen fixation capacity in the component species of contour hedgerows: how important? (springer.com)
  • The implications of hedgerow species with nitrogen (N)-fixation capacity on hedgerow-crop competition and crop productivity have been widely debated. (springer.com)
  • We examined the agronomic significance of N-fixation by comparing the performance of species representing three classes of hedgerow vegetation: A nitrogen-fixing tree legume Gliricidia sepium ), a non-nitrogen fixing tree ( Senna spectabilis syn. (springer.com)
  • Upland rice and maize grain yields and total dry matter were unaffected by tree species, but the nitrogen-fixing tree exerted less competitive effects on the annual crops growing in adjacent rows. (springer.com)
  • We conclude that hedgerow systems composed of a nitrogen-fixing tree did not exert significant advantages compared to a non-fixing tree species, and that factors other than N-fixation were more important determinants for the choice of hedgerow species. (springer.com)
  • This and species-specific differences are best explained by less N fixation in the Atlantic during the last ice age. (caltech.edu)
  • Forests with nitrogen-fixing trees (N-fixers) typically accumulate more carbon (C) in soils than similar forests without N-fixing trees. (upenn.edu)
  • His research focuses on the role and importance of marine microbes in major biogeochemical cycles, particularly those of nitrogen and carbon, both from the perspective of the fundamental ecology of these process in marine ecosystems and their physical, chemical and biotic controls. (springer.com)
  • Considering atom acquisition, for every 100 atoms of carbon, roughly 2 to 20 atoms of nitrogen are assimilated. (wikipedia.org)
  • The use of nitrogen fertilisers releases nitrous oxide, a greenhouse gas which is 300 times more powerful than carbon dioxide. (jic.ac.uk)
  • They focus on modifications with nitrogen, developing a technique with direct nitrogen fixation, carbon-nitrogen bond formation, at the broken edges of graphite frameworks using ball-milling graphite in the presence of nitrogen gas. (nanowerk.com)
  • Nitrogen is the most abundant constituent in air and it is inert diatomic gas while graphite is the most thermodynamically stable form of carbon allotropes," said Prof. Baek. (nanowerk.com)
  • Increased stachyose indicated possible physiological and metabolic changes in carbon and nitrogen pathways and their sources under water stress. (hindawi.com)
  • Are the experimental determinations of the carbon to nitrogen ratio purely circumstantial? (rupress.org)
  • The purpose of this study was to evaluate the effects of different biochar application rates: 0 t ha-1, 5 t ha-1 and 10 t ha-1 on BNF, on microbial biomass carbon and nitrogen (MBC and MBN), and on moss biomass. (helsinki.fi)
  • Some archaea also fix nitrogen, including several methanogenic taxa , which are significant contributors to nitrogen fixation in oxygen-deficient soils. (wikipedia.org)
  • Abiotic nitrogen fixation has been omitted. (wikipedia.org)
  • Finally, high-throughput functional genomics and molecular tools (i.e., miRNAs) are currently very valuable for the identification of many regulatory elements that are good candidates for accurately dissecting the particular N 2 fixation control mechanisms associated with physiological responses to abiotic stresses. (mdpi.com)
  • One key question is whether the limited availability of fixed nitrogen was a factor in life's origin or whether there were ample sources of fixed nitrogen produced by abiotic processes or delivered through the weathering of bolide impact materials to support this early life. (frontiersin.org)
  • Several mechanisms have been proposed to explain nitrogen fixation inhibition under abiotic stresses. (plantphysiol.org)
  • Provided are genetic material and nucleic acid sequences useful in increasing yield, biomass, growth rate, vigor, nitrogen use efficiency and/or abiotic stress. (patents.com)
  • The 14th European Nitrogen Fixation Conference (ENFC), will be held 27-30 August 2020 in Naples , Italy at the Hotel Royal Continental . (fems-microbiology.org)
  • The area of active N 2 fixation is either pink or red in color due to the presence of hemoglobin needed for oxygen transport. (encyclopedia.com)
  • The extremely high temperatures momentarily brought about by a lightning flash are more than sufficient to break apart molecules of nitrogen and oxygen , allowing the nitrogen and oxygen atoms to react with one another and form nitrogen dioxide , which in turn produces nitric acid when it encounters water. (everything2.com)
  • Nitrogen can be fixed by lightning that converts nitrogen and oxygen into NO x ( nitrogen oxides ). (wikipedia.org)
  • Factors such as moisture, temperature, oxygen supply and fertility in the soil can influence fixation. (missouri.edu)
  • An 'extra-ordinary endophyte' this bacterium is one of relatively few that has mechanisms to cope with high levels of sucrose, an acidic pH, a wide range of oxygen environments, nitrogen fixation, as well as having respiratory chain attributes that make it a possible candidate eukaryote proto-mitochondria. (intechopen.com)
  • denitrification occurs in anaerobic conditions and converts the nitrates which aren't taken up by plants (due to lack of oxygen so plants don't survive) into nitrogen gas. (biology-online.org)
  • We identified proteins that changed in abundance in correlation with either nitrogen fixation, dissolved oxygen concentration, or acidification of the growth medium. (nih.gov)
  • Professor Ray Dixon project leader in molecular microbiology at the John Innes Centre said: "This is a really exciting development for synthetic biology because it brings nearer the aim of engineering nitrogen fixation in cereals. (jic.ac.uk)
  • One such search is for a way to allow cereals to fix nitrogen as pulse crops do. (producer.com)
  • This book bridges this knowledge gap for both specialists and non-experts, and provides an in-depth overview of the important aspects of nitrogen fixation as it relates to the marine environment. (springer.com)
  • The proteins that correlated with nitrogen fixation were identified either as known nitrogen fixation proteins or as novel proteins that we predict play roles in aspects of nitrogen fixation based on their proteomic profiles. (nih.gov)
  • To calculate the efficiency of nitrogen fixation an analysis of stable isotopes ( 15 N, 13 C) was carried out on bush beans and reference plants. (actahort.org)
  • The efficiency of nitrogen fixation was very low in all cultivars and ranged from 6.8 to 14.8%.The conclusion was that the investigated cultivars of bush beans could be a good choice for cultivation and can be considered for growing in horticultural production systems. (actahort.org)
  • Mineral nturient defiencies are a major constraint limiting legume nitrogen fixation and yield. (springer.com)
  • The objective of this project was to increase the competitiveness of common bean by improving nitrogen fixation capacity, and therefore, enhancing yield in low fertility soils. (europa.eu)
  • The magnitude of variation and the genetic and phenotypic correlation among seed yield, SNF, estimated as the percentage of nitrogen derived from atmosphere, and related traits were studied in a population of 140 F 4 -derived F 5 recombinant inbred lines, developed from a cross between low- and high-SNF bean genotypes 'Sanilac' and 'Mist', respectively. (springer.com)
  • Appiah FK, Tufuor JK, Amoako-Andoh F (2015) Nitrogen fixation and yield potential of some early-maturing cowpea ( Vigna unguiculata (L.) Walp. (springer.com)
  • Although nitrogen exists in many forms in the soil, it is the nitrate form that primarily affects water quality. (missouri.edu)
  • Kaschuk, G., Hungria, M., Leffelaar P.A., Giller, K.E. and Kuyper, T.W. (2010) Differences in Photosynthetic Behaviour and Leaf Senescence of Soybean [Glycine max (L.) Merrill] Dependent on N2 Fixation or Nitrate Supply. (scirp.org)
  • Fixation processes free up nitrogen atoms from their diatomic form to be used in other ways, but nitrogen does not easily react with other chemicals to form new compounds. (nanowerk.com)
  • Is it possible in theory to discover some catalyst which is able to breakdown nitrogen molecules without enegy spend?In the similar way as Platinum breaks down hydrogen atoms without additional energy required? (thescienceforum.com)
  • nitrite is part of the nitrogen cycle, it's not considered part of fixation. (biology-online.org)
  • Nitrogen fixation is essential to life because fixed inorganic nitrogen compounds are required for the biosynthesis of all nitrogen-containing organic compounds , such as amino acids and proteins , nucleoside triphosphates and nucleic acids . (wikipedia.org)
  • Nitrogen in these forms can then be used in the manufacture of nitrogen-requiring molecules such as the amino acids that make up proteins . (rationalwiki.org)
  • Both proteins are sensitive to biochemical signals that occur in the bacterial cell when conditions are right for nitrogen fixation. (innovations-report.com)
  • These are then expressed in the host cell as huge proteins known as "polyproteins" which are subsequently cut by a specific protease enzyme to release the individual nitrogen fixation components. (jic.ac.uk)
  • In Brazil alone, N 2 fixation contributes the equivalent of 2.5 million tons of fertilizer nitrogen annually to agricultural production and is essential to a country with limited natural gas reserves for fertilizer nitrogen production. (encyclopedia.com)
  • As part of the nitrogen cycle , it is essential for agriculture and the manufacture of fertilizer . (wikipedia.org)
  • However, a great deal of fossil fuel is required for the production and delivery of nitrogen fertilizer. (wiley.com)
  • In combination with existing information, utilizing these abundant genetic molecular tools will enable us to identify the specific mechanisms underlying the regulation of N 2 fixation. (mdpi.com)
  • This download Genetic Engineering for Nitrogen Fixation 1977 continues warehousing editors in newsstand, encouragement, supply, and school, and mining media in time or life. (literary-liaisons.com)
  • Artists and Writers Colonies: schools, reconstructions, and editors for the early download Genetic Engineering for Nitrogen Fixation 1977. (literary-liaisons.com)
  • Zaure RozmatMuch of the content download Genetic Engineering for Nitrogen Fixation 1977 in Kazakhstan places shortly highly from editors over how to get the result, but a measurement as actual as number: initially, comics have enshrined about how younger Oftentimes will create a other degree. (literary-liaisons.com)
  • there, operational subsequent students see provided aimed not for several, considering older authors digital and various that their others are submitted signalized to a extensive, more same download Genetic Engineering for Nitrogen often, provides Rozmat. (literary-liaisons.com)
  • Dr. D.L.N Rao, Network Coordinator (Biofertilizers), the PI and Consortium leader of the project said the project will address the crucial issue of improving rhizobial strains for greater competitiveness and higher potential to fix nitrogen in pigeon pea both by natural selection and genetic engineering as also the ability of rice to benefit from nitrogen fixing endophytes. (org.in)
  • A long-standing puzzle 2 is that trees capable of nitrogen fixation are abundant in nitrogen-rich tropical forests, but absent or restricted to early successional stages in nitrogen-poor extra-tropical forests. (nature.com)
  • punctulatushindgut symbionts exposedin vivoto 15 N 2 supports the hypothesis thatBarbulanymphaectosymbionts are capable of nitrogen fixation. (osti.gov)
  • This must be thoroughly studied in the future since there is no unifying theory that explains all of the aspects involved in regulating N 2 fixation rates to date. (mdpi.com)
  • Jenny, H. Causes of the high nitrogen and organic matter content of certain tropical forest soils. (nature.com)
  • However, the availability of nitrogen is limited in many soils and although the earth's atmosphere consists of 78.1% nitrogen gas (N2) plants are unable to use this form of nitrogen. (wiley.com)
  • Environmental factors such as drought, elevated temperature, salinity, soil acidity and rising CO2 are known to dramatically affect the symbiotic process and thus play a part in determining the actual amount of nitrogen fixed by a given legume in the field. (springer.com)
  • General estimates of the amount of nitrogen fixed range from 50 to 100 lb N/acre for annuals and about 200 lb N/acre for alfalfa. (tamu.edu)
  • Gaseous nitrogen diffusing into the soil from the air is converted into useable nitrogen by the mechanism of the leguminous plants, combined with the bacterial action of the microorganisms living in its roots. (rawfoodexplained.com)
  • The aim of this study was to determine the potential of microbial mats to fix nitrogen and to identify individual functional groups of microorganisms that contribute to it. (uva.nl)
  • Early studies using acetylene reduction have suggested that macroalgae may contribute to nitrogen enrichment of waters near coral reefs via nitrogen fixation by their epiphytic cynaphytes. (upenn.edu)
  • The enzymes that carry out the reduction of nitrogen are known in the literature as nitrogenases. (rationalwiki.org)
  • The fixation decrease was most likely a response to a known ice age reduction in ocean N loss, and it would have worked to balance the ocean N budget and to curb ice age-to-interglacial change in the N inventory. (caltech.edu)
  • Conformational change induced by ATP hydrolysis brings reductase close to the Mo-Fe center of nitrogen reduction. (coursehero.com)
  • We show that in the tropics, transient soil nitrogen deficits following disturbance and rapid tree growth favour a facultative strategy and the coexistence of fixers and non-fixers. (nature.com)
  • Figure 2: Forest composition as a function of soil nitrogen. (nature.com)
  • Net soil nitrogen accrual from the incorporation of grain legume residue in Africa can be as much as 140 kg N ha -1 depending on the legume type and variety. (wur.nl)
  • An Overview of Key Soil Nitrogen Cycling Transformations -- Figure 1. (ufl.edu)
  • This book is intended to provide an overview of N2 fixation research for marine researchers, while providing a reference on marine research for researchers in other fields, including terrestrial N2 fixation. (springer.com)
  • Quantitative overview of N2 fixation in Nostoc punctiforme ATCC 29133 through cellular enrichments and iTRAQ shotgun proteomics. (umassmed.edu)
  • In this review general techniques for assessing nutrient involvement in symbiotic nitrogen fixation are described and specific methods are outlined for determining which developmental phase of the symbiosis is most sensitive to nutrient deficiency. (springer.com)
  • The ectosymbiont genome carried two complete operons for nitrogen fixation, a urea transporter, and a urease, indicating the availability of nitrogen as a driving force behind the symbiosis. (osti.gov)
  • A crucial arginine residue is required for a conformational switch in NifL to regulate nitrogen fixation in Azotobacter vinelandii. (innovations-report.com)
  • To date, our efforts have resulted in engineered Synechocystis 6803 strains that, remarkably, have more than 30% of the N 2 fixation activity of Cyanothece 51142, the highest such activity established in any nondiazotrophic oxygenic photosynthetic organism. (asm.org)
  • In the first experiment, the nodulation and nitrogen fixation capacity of new strains were evaluated, in comparison to the commercial strains CIAT-899 and PRF-81 and to native soil population. (scielo.br)
  • The LBMP-4BR and LBMP-12BR new strains are among the ones with greatest nodulation and fixation capacity and exhibit differential responses when mixed to PRF-81. (scielo.br)
  • Certain strains of the obligate nitrogen-fixing bacterial endophyte Gluconacetobacter diazotrophicus have the necessary attributes for this role. (intechopen.com)
  • Nitrogen is arguably the most important nutrient required by plants. (wiley.com)
  • An important nutrient is nitrogen, which is derived from organic sources in the soil. (maximumyield.com)
  • Measured N2 fixation rates and the implied large fraction of new production supported by diazotrophy emphasize the importance of N2 fixation in nutrient dynamics in the NPSG. (hawaii.edu)
  • BMAA Inhibits Nitrogen Fixation in the Cyanobacterium Nostoc sp. (mdpi.com)
  • Here, we examined the effects of BMAA on the physiology of the filamentous nitrogen-fixing cyanobacterium Nostoc sp. (mdpi.com)
  • This gives the scientists an important clue about the key processes which operate the lock that controls nitrogen fixation. (innovations-report.com)
  • however, the estimated fixation rate was similar to other published results, suggesting that processes other than cellular growth rate may determine the abundance of unicellular diazotrophs. (columbia.edu)
  • A download nitrogen fixing actinorhizal symbioses nitrogen to either processes a mainstream front to amplify a gallon or job. (thelostdogs.com)
  • In order to make the process more cost-effective, chemists have focused on the development of new systems that can transform nitrogen into useful compounds using mild low-energy conditions. (eurekalert.org)
  • Nitrogen fixation is any process which converts gaseous nitrogen into nitrogen-containing compound s. (everything2.com)
  • Under artificial conditions, nitrogen fixation is done on a large scale by the Haber-Bosch process . (everything2.com)
  • The dominant technology for abiological nitrogen fixation is the Haber process, which uses an iron-based heterogeneous catalysts and H2 to convert N2 to NH3. (wikipedia.org)
  • In rare cases, metals react with nitrogen gas to give nitrides, a process called nitriding. (wikipedia.org)
  • In a related process, trimethylsilyl chloride, lithium and nitrogen react in the presence of a catalyst to give tris(trimethylsilyl)amine, which can be further elaborated. (wikipedia.org)
  • Nitrogen fixation is an intricate and delicate process which requires a balance of numerous key components. (jic.ac.uk)
  • this system participates in the recycling of hydrogen that otherwise would be lost as a by-product of the nitrogen fixation process. (sciencemag.org)
  • This artificial N-fixation process was established in 1913 and uses a catalyst (iron with a small amount of aluminum added) at high pressure (as much as 5.06 × 10 7 Pa) and high temperature (600-800 K) consuming large amounts of fossil fuel. (intechopen.com)
  • The most common method of industrial nitrogen fixation is the Harber-Bosch process, which requires extremely harsh conditions, 200 atm of pressure and 400 C of temperature. (nanowerk.com)
  • Along the way, the research team discovered a novel nitrogen fixation process. (nanowerk.com)
  • The N 2 -fixation process itself is influence by soil temperature. (tamu.edu)
  • Do not hypotheses concerning the fixation of nitrogen in the evolutionary process, which are based on the conception that energy is required, lose some of their significance? (rupress.org)
  • [2] Looser non-symbiotic relationships between diazotrophs and plants are often referred to as associative, as seen in nitrogen fixation on rice roots. (wikipedia.org)
  • Diazotrophs are important in the maintenance of the biogeochemical nitrogen cycle. (rationalwiki.org)
  • Nearly all (95%) N2 fixation in the euphotic zone (0 - 125 m) occurred in the upper 75 m and was mostly supported (57 - 76%) by diazotrophs less than 10 µm in diameter. (hawaii.edu)
  • Temporal and depth variability in rates of dinitrogen (N2) fixation at Stn. (hawaii.edu)
  • This report establishes a baseline for the ultimate goal of engineering nitrogen fixation ability in crop plants. (asm.org)
  • Nitrogen in crop production: an account of global flows. (harvard.edu)
  • They didn't observe any significant treatment differences in nitrogen-fixing soybean plants, though they did see some minor treatment effects in non-nodulating mutants. (lternet.edu)
  • Soybean plants that depend upon symbiotic nitrogen fixation for their N have a higher P requirement than their counterparts supplied with fixed N from an external source. (hawaii.edu)
  • This paper details current knowledge about nitrogen fixation by cyanobacterial (blue-green algal) heterocysts. (springer.com)
  • Daimon and Yoshioka, 2001 ) and moreover, nitrogen assimilation, whether from N 2 fixation or inorganic sources, had a localized effect on root development ( Singleton and van Kessel, 1987 ). (plantphysiol.org)
  • Antipchuk AF, Kantselyaruk RM, Rangelova VN, Skochinskaya NN, Tantsyurenko EV (1990) Relation between the photo-assimilation activity indices of leguminous plants and their symbiotic nitrogen fixation. (springer.com)
  • Therefore, the focus of this review is the state-of-the-art engineering of efficient photocatalysts for dinitrogen (N 2 ) fixation toward NH 3 synthesis. (rsc.org)
  • As such, it is anticipated that this review will shed new light on photocatalytic N 2 fixation and NH 3 synthesis and will also provide a blueprint for further investigations and momentous breakthroughs in next-generation catalyst design. (rsc.org)