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Carbon: 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.Nitrogen: 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.Lyases: A class of enzymes that catalyze the cleavage of C-C, C-O, and C-N, and other bonds by other means than by hydrolysis or oxidation. (Enzyme Nomenclature, 1992) EC 4.Chondroitin Lyases: Enzymes which catalyze the elimination of delta-4,5-D-glucuronate residues from polysaccharides containing 1,4-beta-hexosaminyl and 1,3-beta-D-glucuronosyl or 1,3-alpha-L-iduronosyl linkages thereby bringing about depolymerization. EC 4.2.2.4 acts on chondroitin sulfate A and C as well as on dermatan sulfate and slowly on hyaluronate. EC 4.2.2.5 acts on chondroitin sulfate A and C.Nitrogen Fixation: 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.Carbon Dioxide: A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.Carbon Monoxide: Carbon monoxide (CO). A poisonous colorless, odorless, tasteless gas. It combines with hemoglobin to form carboxyhemoglobin, which has no oxygen carrying capacity. The resultant oxygen deprivation causes headache, dizziness, decreased pulse and respiratory rates, unconsciousness, and death. (From Merck Index, 11th ed)Nanotubes, Carbon: Nanometer-sized tubes composed mainly of CARBON. Such nanotubes are used as probes for high-resolution structural and chemical imaging of biomolecules with ATOMIC FORCE MICROSCOPY.Pectobacterium chrysanthemi: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that causes vascular wilts on a wide range of plant species. It was formerly named Erwinia chrysanthemi.Nitrogen Isotopes: 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.Chondroitinases and Chondroitin Lyases: Enzymes which catalyze the elimination of glucuronate residues from chondroitin A,B, and C or which catalyze the hydrolysis of sulfate groups of the 2-acetamido-2-deoxy-D-galactose 6-sulfate units of chondroitin sulfate. EC 4.2.2.-.Nitrogen Compounds: Inorganic compounds that contain nitrogen as an integral part of the molecule.Pectins: High molecular weight polysaccharides present in the cell walls of all plants. Pectins cement cell walls together. They are used as emulsifiers and stabilizers in the food industry. They have been tried for a variety of therapeutic uses including as antidiarrheals, where they are now generally considered ineffective, and in the treatment of hypercholesterolemia.Nitrogen Cycle: 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.Nitrogen Dioxide: 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.Blood Urea Nitrogen: 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)Phycobiliproteins: Light harvesting proteins found in phycobilisomes.Chicory: A thick-rooted perennial (Cichorium intybus) native to Europe but widely grown for its young leaves used as salad greens and for its roots, dried and ground-roasted, used to flavor or adulterate coffee. (From Webster, 3d ed)Carbon Monoxide Poisoning: Toxic asphyxiation due to the displacement of oxygen from oxyhemoglobin by carbon monoxide.Carbon Isotopes: Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.Reactive Nitrogen Species: 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.Aldehyde-Lyases: Enzymes that catalyze a reverse aldol condensation. A molecule containing a hydroxyl group and a carbonyl group is cleaved at a C-C bond to produce two smaller molecules (ALDEHYDES or KETONES). EC 4.1.2.Molecular Sequence Data: 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.Carbon-Oxygen Lyases: Enzymes that catalyze the cleavage of a carbon-oxygen bond by means other than hydrolysis or oxidation. EC 4.2.Nitrogen Oxides: Inorganic oxides that contain nitrogen.Erwinia: A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria whose organisms are associated with plants as pathogens, saprophytes, or as constituents of the epiphytic flora.Oxo-Acid-Lyases: Enzymes that catalyze the cleavage of a carbon-carbon bond of a 3-hydroxy acid. (Dorland, 28th ed) EC 4.1.3.Heparin Lyase: An enzyme of the isomerase class that catalyzes the eliminative cleavage of polysaccharides containing 1,4-linked D-glucuronate or L-iduronate residues and 1,4-alpha-linked 2-sulfoamino-2-deoxy-6-sulfo-D-glucose residues to give oligosaccharides with terminal 4-deoxy-alpha-D-gluc-4-enuronosyl groups at their non-reducing ends. (From Enzyme Nomenclature, 1992) EC 4.2.2.7.PII Nitrogen Regulatory Proteins: A family of signal transducing adaptor proteins that control the METABOLISM of NITROGEN. They are primarily found in prokaryotes.Carbon Tetrachloride: A solvent for oils, fats, lacquers, varnishes, rubber waxes, and resins, and a starting material in the manufacturing of organic compounds. Poisoning by inhalation, ingestion or skin absorption is possible and may be fatal. (Merck Index, 11th ed)Carbon Sequestration: Any of several processes for the permanent or long-term artificial or natural capture or removal and storage of carbon dioxide and other forms of carbon, through biological, chemical or physical processes, in a manner that prevents it from being released into the atmosphere.Polygalacturonase: A cell wall-degrading enzyme found in microorganisms and higher plants. It catalyzes the random hydrolysis of 1,4-alpha-D-galactosiduronic linkages in pectate and other galacturonans. EC 3.2.1.15.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Bacterial Proteins: Proteins found in any species of bacterium.Amino Acid Sequence: 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.Nitrates: Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.Ammonia: 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.Alginates: Salts of alginic acid that are extracted from marine kelp and used to make dental impressions and as absorbent material for surgical dressings.Carbon Disulfide: A colorless, flammable, poisonous liquid, CS2. It is used as a solvent, and is a counterirritant and has local anesthetic properties but is not used as such. It is highly toxic with pronounced CNS, hematologic, and dermatologic effects.Biomass: 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.Rhodophyta: Plants of the division Rhodophyta, commonly known as red algae, in which the red pigment (PHYCOERYTHRIN) predominates. However, if this pigment is destroyed, the algae can appear purple, brown, green, or yellow. Two important substances found in the cell walls of red algae are AGAR and CARRAGEENAN. Some rhodophyta are notable SEAWEED (macroalgae).Fertilizers: 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.Soil: The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.Sphingomonas: A genus of gram-negative, aerobic, rod-shaped bacteria characterized by an outer membrane that contains glycosphingolipids but lacks lipopolysaccharide. They have the ability to degrade a broad range of substituted aromatic compounds.Hexuronic Acids: Term used to designate tetrahydroxy aldehydic acids obtained by oxidation of hexose sugars, i.e. glucuronic acid, galacturonic acid, etc. Historically, the name hexuronic acid was originally given to ascorbic acid.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Isocitrate Lyase: A key enzyme in the glyoxylate cycle. It catalyzes the conversion of isocitrate to succinate and glyoxylate. EC 4.1.3.1.Kinetics: The rate dynamics in chemical or physical systems.Phycobilins: Open chain tetrapyrroles that function as light harvesting chromophores in PHYCOBILIPROTEINS.Chondroitin ABC Lyase: An enzyme that catalyzes the eliminative degradation of polysaccharides containing 1,4-beta-D-hexosaminyl and 1,3-beta-D-glucuronosyl or 1,3-alpha-L-iduronosyl linkages to disaccharides containing 4-deoxy-beta-D-gluc-4-enuronosyl groups. (Enzyme Nomenclature, 1992)Quaternary Ammonium Compounds: 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.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Cloning, Molecular: 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.Pseudomonas: A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.Cytochromes c1: The 30-kDa membrane-bound c-type cytochrome protein of mitochondria that functions as an electron donor to CYTOCHROME C GROUP in the mitochondrial and bacterial RESPIRATORY CHAIN. (From Enzyme Nomenclature, 1992, p545)Escherichia coli: 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.Carbon Tetrachloride PoisoningSequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Glutamate-Ammonia Ligase: 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.Genes, Bacterial: The functional hereditary units of BACTERIA.Flavobacterium: A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in SOIL and WATER. Its organisms are also found in raw meats, MILK and other FOOD, hospital environments, and human clinical specimens. Some species are pathogenic in humans.Bacteroides: A genus of gram-negative, anaerobic, rod-shaped bacteria. Its organisms are normal inhabitants of the oral, respiratory, intestinal, and urogenital cavities of humans, animals, and insects. Some species may be pathogenic.Culture Media: 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.Amino Acids: 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.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Glucuronic Acid: A sugar acid formed by the oxidation of the C-6 carbon of GLUCOSE. In addition to being a key intermediate metabolite of the uronic acid pathway, glucuronic acid also plays a role in the detoxification of certain drugs and toxins by conjugating with them to form GLUCURONIDES.Urea: A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.Symbiosis: 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.Atmosphere: The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)Photosynthesis: 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)Adenylosuccinate Lyase: An enzyme that, in the course of purine ribonucleotide biosynthesis, catalyzes the conversion of 5'-phosphoribosyl-4-(N-succinocarboxamide)-5-aminoimidazole to 5'-phosphoribosyl-4-carboxamide-5-aminoimidazole and the conversion of adenylosuccinic acid to AMP. EC 4.3.2.2.Streptococcus anginosus: A species of gram-positive bacteria in the STREPTOCOCCUS MILLERI GROUP. It is the most frequently seen isolate of that group, has a proclivity for abscess formation, and is most often isolated from the blood, gastrointestinal, and urogenital tract.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Hevea: A plant genus of the family EUPHORBIACEAE, order Euphorbiales, subclass Rosidae. Commercial natural RUBBER is mainly obtained from Hevea brasiliensis but also from some other plants.Plants: 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.Plant Leaves: 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)Mutation: 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.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Nitrogenase: An enzyme system that catalyzes the fixing of nitrogen in soil bacteria and blue-green algae (CYANOBACTERIA). EC 1.18.6.1.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Nitrogen Mustard Compounds: A group of alkylating agents derived from mustard gas, with the sulfur replaced by nitrogen. They were formerly used as toxicants and vesicants, but now function as antineoplastic agents. These compounds are also powerful mutagens, teratogens, immunosuppressants, and carcinogens.Fungi: A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including MUSHROOMS; YEASTS; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.Ecosystem: 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)Oxidation-Reduction: 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).Carbon Footprint: A measure of the total greenhouse gas emissions produced by an individual, organization, event, or product. It is measured in units of equivalent kilograms of CARBON DIOXIDE generated in a given time frame.Plant Roots: 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)Glycoside HydrolasesCarbon Radioisotopes: Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Biodegradation, Environmental: Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.Trees: Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.Uronic Acids: Acids derived from monosaccharides by the oxidation of the terminal (-CH2OH) group farthest removed from the carbonyl group to a (-COOH) group. (From Stedmans, 26th ed)Glycosaminoglycans: Heteropolysaccharides which contain an N-acetylated hexosamine in a characteristic repeating disaccharide unit. The repeating structure of each disaccharide involves alternate 1,4- and 1,3-linkages consisting of either N-acetylglucosamine or N-acetylgalactosamine.Proteus vulgaris: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that occurs in soil, fecal matter, and sewage. It is an opportunistic pathogen and causes cystitis and pyelonephritis.Disaccharides: Oligosaccharides containing two monosaccharide units linked by a glycosidic bond.Carbon-Nitrogen Lyases: Enzymes that catalyze the cleavage of a carbon-nitrogen bond by means other than hydrolysis or oxidation. Subclasses are the AMMONIA-LYASES, the AMIDINE-LYASES, the amine-lyases, and other carbon-nitrogen lyases. EC 4.3.Carbon-Carbon Lyases: Enzymes that catalyze the cleavage of a carbon-carbon bond by means other than hydrolysis or oxidation. This subclass contains the DECARBOXYLASES, the ALDEHYDE-LYASES, and the OXO-ACID-LYASES. EC 4.1.Glutamine: 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.Sulfonium Compounds: Sulfur compounds in which the sulfur atom is attached to three organic radicals and an electronegative element or radical.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Oxygen: 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.Chondroitin Sulfates: Derivatives of chondroitin which have a sulfate moiety esterified to the galactosamine moiety of chondroitin. Chondroitin sulfate A, or chondroitin 4-sulfate, and chondroitin sulfate C, or chondroitin 6-sulfate, have the sulfate esterified in the 4- and 6-positions, respectively. Chondroitin sulfate B (beta heparin; DERMATAN SULFATE) is a misnomer and this compound is not a true chondroitin sulfate.AcetyleneCatalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.Carbohydrate Sequence: The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.Soil Microbiology: The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.Carbohydrate Metabolism: Cellular processes in biosynthesis (anabolism) and degradation (catabolism) of CARBOHYDRATES.Bacteria: 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.Fermentation: Anaerobic degradation of GLUCOSE or other organic nutrients to gain energy in the form of ATP. End products vary depending on organisms, substrates, and enzymatic pathways. Common fermentation products include ETHANOL and LACTIC ACID.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Bacillus: A genus of BACILLACEAE that are spore-forming, rod-shaped cells. Most species are saprophytic soil forms with only a few species being pathogenic.Dermatan Sulfate: A naturally occurring glycosaminoglycan found mostly in the skin and in connective tissue. It differs from CHONDROITIN SULFATE A (see CHONDROITIN SULFATES) by containing IDURONIC ACID in place of glucuronic acid, its epimer, at carbon atom 5. (from Merck, 12th ed)Glucose: A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.