Sulfur
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.
Carbon
Lyases
Sulfur Compounds
Inorganic or organic compounds that contain sulfur as an integral part of the molecule.
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.
Sulfur Dioxide
Carbon Dioxide
A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.
Sulfur Isotopes
Stable sulfur atoms that have the same atomic number as the element sulfur, but differ in atomic weight. S-33, 34, and 36 are stable sulfur isotopes.
Amino Acids, Sulfur
'Sulfur-containing amino acids' are a category of amino acids, the building blocks of proteins, that include methionine and cysteine, which contain sulfur atoms as part of their side chains, playing crucial roles in protein structure, enzyme function, and antioxidant defense.
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
Chondroitinases and Chondroitin Lyases
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.
Mustard Gas
Severe irritant and vesicant of skin, eyes, and lungs. It may cause blindness and lethal lung edema and was formerly used as a war gas. The substance has been proposed as a cytostatic and for treatment of psoriasis. It has been listed as a known carcinogen in the Fourth Annual Report on Carcinogens (NTP-85-002, 1985) (Merck, 11th ed).
Sulfides
Carbon Monoxide Poisoning
Chicory
Sulfur Oxides
Inorganic oxides of sulfur.
Aldehyde-Lyases
Carbon Isotopes
Carbon-Oxygen Lyases
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.
Erwinia
Oxo-Acid-Lyases
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.
Chlorobi
A phylum of anoxygenic, phototrophic bacteria including the family Chlorobiaceae. They occur in aquatic sediments, sulfur springs, and hot springs and utilize reduced sulfur compounds instead of oxygen.
Carbon Tetrachloride
Substrate Specificity
Sulfonium Compounds
Sulfur compounds in which the sulfur atom is attached to three organic radicals and an electronegative element or radical.
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.
Carbon Disulfide
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.
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.
Oxidoreductases Acting on Sulfur Group Donors
Oxidoreductases with specificity for oxidation or reduction of SULFUR COMPOUNDS.
Alginates
Sulfur Hexafluoride
Sulfur hexafluoride. An inert gas used mainly as a test gas in respiratory physiology. Other uses include its injection in vitreoretinal surgery to restore the vitreous chamber and as a tracer in monitoring the dispersion and deposition of air pollutants.
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).
Chromatiaceae
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).
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.
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.
Chemical Warfare Agents
Isocitrate Lyase
Sulfurtransferases
Enzymes which transfer sulfur atoms to various acceptor molecules. EC 2.8.1.
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)
Hydrogen-Ion Concentration
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.
Sulfur Acids
Inorganic or organic acids that contain sulfur as an integral part of the molecule.
Cloning, Molecular
Cysteine
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
Pseudomonas
Sequence 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.
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 Poisoning
Carbon tetrachloride poisoning is a condition characterized by the systemic toxicity induced by exposure to carbon tetrachloride, a volatile chlorinated hydrocarbon solvent, causing central nervous system depression, cardiovascular collapse, and potentially fatal liver and kidney damage.
Chlorobium
Cytochromes c1
Sequence Analysis, DNA
Hydrogen Sulfide
Flavobacterium
Atmosphere
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.
Chromatium
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.
DNA, Bacterial
Deoxyribonucleic acid that makes up the genetic material of bacteria.
Adenylosuccinate Lyase
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.
Hevea
Gene Expression Regulation, Bacterial
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
Seawater
The salinated water of OCEANS AND SEAS that provides habitat for marine organisms.
Acidithiobacillus
A genus of gram-negative rod-shaped bacteria in the class GAMMAPROTEOBACTERIA. They are obligately acidophilic and aerobic, using reduced SULFUR COMPOUNDS to support AUTOTROPHIC GROWTH.
Air Pollutants
Any substance in the air which could, if present in high enough concentration, harm humans, animals, vegetation or material. Substances include GASES; PARTICULATE MATTER; and volatile ORGANIC CHEMICALS.
Genes, Bacterial
The functional hereditary units of BACTERIA.
Catalysis
Sulfur-Reducing Bacteria
A group of gram-negative, anaerobic bacteria that is able to oxidize acetate completely to carbon dioxide using elemental sulfur as the electron acceptor.
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.
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.
Base Sequence
Geologic Sediments
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)
Crystallography, X-Ray
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.
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
Cysteine Synthase
An enzyme that catalyzes the biosynthesis of cysteine in microorganisms and plants from O-acetyl-L-serine and hydrogen sulfide. This enzyme was formerly listed as EC 4.2.99.8.
Anaerobiosis
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)
Models, Molecular
Iron-Sulfur Proteins
A group of proteins possessing only the iron-sulfur complex as the prosthetic group. These proteins participate in all major pathways of electron transport: photosynthesis, respiration, hydroxylation and bacterial hydrogen and nitrogen fixation.
Autotrophic Processes
The processes by which organisms use simple inorganic substances such as gaseous or dissolved carbon dioxide and inorganic nitrogen as nutrient sources. Contrasts with heterotrophic processes which make use of organic materials as the nutrient supply source. Autotrophs can be either chemoautotrophs (or chemolithotrophs), largely ARCHAEA and BACTERIA, which also use simple inorganic substances for their metabolic energy reguirements; or photoautotrophs (or photolithotrophs), such as PLANTS and CYANOBACTERIA, which derive their energy from light. Depending on environmental conditions some organisms can switch between different nutritional modes (autotrophy; HETEROTROPHY; chemotrophy; or PHOTOTROPHY) to utilize different sources to meet their nutrient and energy requirements.
Uronic Acids
Glycoside Hydrolases
Glycoside Hydrolases are a class of enzymes that catalyze the hydrolysis of glycosidic bonds, resulting in the breakdown of complex carbohydrates and oligosaccharides into simpler sugars.
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.
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.
Glycosaminoglycans
Proteus vulgaris
Biomass
Carbon 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.
RNA, Ribosomal, 16S
Carbon Compounds, Inorganic
Inorganic compounds that contain carbon as an integral part of the molecule but are not derived from hydrocarbons.
Thiobacillus
A genus of gram-negative, rod-shaped bacteria that derives energy from the oxidation of one or more reduced sulfur compounds. Many former species have been reclassified to other classes of PROTEOBACTERIA.
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.
Hydrogensulfite Reductase
An enzyme found primarily in SULFUR-REDUCING BACTERIA where it plays an important role in the anaerobic carbon oxidation pathway.
Epsilonproteobacteria
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)
Phototrophic Processes
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.
Mutation
Gammaproteobacteria
A group of the proteobacteria comprised of facultatively anaerobic and fermentative gram-negative bacteria.
Thiosulfate Sulfurtransferase
An enzyme that catalyzes the transfer of the planetary sulfur atom of thiosulfate ion to cyanide ion to form thiocyanate ion. EC 2.8.1.1.
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.
Carbohydrate Sequence
Biocatalysis
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.
Binding Sites
Oxidoreductases
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)
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.
Air Pollution
The presence of contaminants or pollutant substances in the air (AIR POLLUTANTS) that interfere with human health or welfare, or produce other harmful environmental effects. The substances may include GASES; PARTICULATE MATTER; or volatile ORGANIC CHEMICALS.
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)
Sulfur Group Transferases
Thiotrichaceae
Catalytic Domain
Electrophoresis, Polyacrylamide Gel
Hydrogen
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.
DNA-(Apurinic or Apyrimidinic Site) Lyase
A DNA repair enzyme that catalyses the excision of ribose residues at apurinic and apyrimidinic DNA sites that can result from the action of DNA GLYCOSYLASES. The enzyme catalyzes a beta-elimination reaction in which the C-O-P bond 3' to the apurinic or apyrimidinic site in DNA is broken, leaving a 3'-terminal unsaturated sugar and a product with a terminal 5'-phosphate. This enzyme was previously listed under EC 3.1.25.2.
Acetates
Cystathionine gamma-Lyase
A multifunctional pyridoxal phosphate enzyme. In the final step in the biosynthesis of cysteine it catalyzes the cleavage of cystathionine to yield cysteine, ammonia, and 2-ketobutyrate. EC 4.4.1.1.
Water Microbiology
Oxygen
Cystine
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.
Protein Conformation
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Iron
A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.
N-Glycosyl Hydrolases
DNA, Ribosomal
Soot
A dark powdery deposit of unburned fuel residues, composed mainly of amorphous CARBON and some HYDROCARBONS, that accumulates in chimneys, automobile mufflers and other surfaces exposed to smoke. It is the product of incomplete combustion of carbon-rich organic fuels in low oxygen conditions. It is sometimes called lampblack or carbon black and is used in INK, in rubber tires, and to prepare CARBON NANOTUBES.
Sulfate Adenylyltransferase
Chromatography
Techniques used to separate mixtures of substances based on differences in the relative affinities of the substances for mobile and stationary phases. A mobile phase (fluid or gas) passes through a column containing a stationary phase of porous solid or liquid coated on a solid support. Usage is both analytical for small amounts and preparative for bulk amounts.
Carboxyhemoglobin
Carboxyhemoglobin is a form of hemoglobin in which the heme group is chemically bonded to carbon monoxide, reducing its ability to transport oxygen and leading to toxic effects when present in high concentrations.
Chromatography, High Pressure Liquid
Methane
Molybdenum
Chromatography, Gel
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.
Volcanic Eruptions
The ash, dust, gases, and lava released by volcanic explosion. The gases are volatile matter composed principally of about 90% water vapor, and carbon dioxide, sulfur dioxide, hydrogen, carbon monoxide, and nitrogen. The ash or dust is pyroclastic ejecta and lava is molten extrusive material consisting mainly of magnesium silicate. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Acidianus
A genus of facultatively anaerobic coccoid ARCHAEA, in the family SULFOLOBACEAE. Cells are highly irregular in shape and thermoacidophilic. Lithotrophic growth occurs aerobically via sulfur oxidation in some species. Distribution includes solfataric springs and fields, mudholes, and geothermically heated acidic marine environments.
Isoenzymes
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.
Carbohydrate Metabolism
Gases
The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)
Chromatography, Ion Exchange
Oceans and Seas
Ecosystem
Sulfuric Acids
Inorganic and organic derivatives of sulfuric acid (H2SO4). The salts and esters of sulfuric acid are known as SULFATES and SULFURIC ACID ESTERS respectively.
Multigene Family
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)
Arylsulfatases
Enzymes that catalyze the hydrolysis of a phenol sulfate to yield a phenol and sulfate. Arylsulfatase A, B, and C have been separated. A deficiency of arylsulfatases is one of the causes of metachromatic leukodystrophy (LEUKODYSTROPHY, METACHROMATIC). EC 3.1.6.1.
DNA Glycosylases
A family of DNA repair enzymes that recognize damaged nucleotide bases and remove them by hydrolyzing the N-glycosidic bond that attaches them to the sugar backbone of the DNA molecule. The process called BASE EXCISION REPAIR can be completed by a DNA-(APURINIC OR APYRIMIDINIC SITE) LYASE which excises the remaining RIBOSE sugar from the DNA.
Intramolecular Lyases
Metabolic Networks and Pathways
Environmental Monitoring
The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.
Enzyme Stability
Spectrum Analysis
Protein Binding
Soil Microbiology
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.
Aerobiosis
Life or metabolic reactions occurring in an environment containing oxygen.
Acidithiobacillus thiooxidans
A strictly autotrophic species of bacteria that oxidizes sulfur and thiosulfate to sulfuric acid. It was formerly called Thiobacillus thiooxidans.
Magnetic Resonance Spectroscopy
Glutathione
Bacteriochlorophylls
Pyrrole containing pigments found in photosynthetic bacteria.
Heterotrophic Processes
The processes by which organisms utilize organic substances as their nutrient sources. Contrasts with AUTOTROPHIC PROCESSES which make use of simple inorganic substances as the nutrient supply source. Heterotrophs can be either chemoheterotrophs (or chemoorganotrophs) which also require organic substances such as glucose for their primary metabolic energy requirements, or photoheterotrophs (or photoorganotrophs) which derive their primary energy requirements from light. 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.
Chemoautotrophic Growth
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.
Cystathionine
Cystathionine is an intermediate sulfur-containing amino acid in the transsulfuration pathway, formed from homocysteine and serine by the enzyme cystathionine beta-synthase, which is involved in the biosynthesis of cysteine and glutathione.
Heparitin Sulfate
Trees
Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.
Sulfur Radioisotopes
Unstable isotopes of sulfur that decay or disintegrate spontaneously emitting radiation. S 29-31, 35, 37, and 38 are radioactive sulfur isotopes.
Crystallization
Amino Acids
Metalloproteins
Cell Wall
Tetrathionic Acid
Oligosaccharides
Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.
Graphite
An allotropic form of carbon that is used in pencils, as a lubricant, and in matches and explosives. It is obtained by mining and its dust can cause lung irritation.
Geological Phenomena
Spectrophotometry
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.