A flammable, poisonous gas with a characteristic odor of rotten eggs. It is used in the manufacture of chemicals, in metallurgy, and as an analytical reagent. (From Merck Index, 11th ed)
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.
Chemical groups containing the covalent sulfur bonds -S-. The sulfur atom can be bound to inorganic or organic moieties.
A multifunctional pyridoxal phosphate enzyme. In the second stage of cysteine biosynthesis it catalyzes the reaction of homocysteine with serine to form cystathionine with the elimination of water. Deficiency of this enzyme leads to HYPERHOMOCYSTEINEMIA and HOMOCYSTINURIA. EC 4.2.1.22.
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 low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.
A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.
Hydrocarbons with at least one triple bond in the linear portion, of the general formula Cn-H2n-2.
Inorganic salts of thiosulfuric acid possessing the general formula R2S2O3.
Compounds containing carbon-phosphorus bonds in which the phosphorus component is also bonded to one or more sulfur atoms. Many of these compounds function as CHOLINERGIC AGENTS and as INSECTICIDES.
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.
Enzymes which transfer sulfur atoms to various acceptor molecules. EC 2.8.1.
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
Organic compounds containing the radical -CSNH2.
Inorganic or organic compounds that contain sulfur as an integral part of the molecule.
A compound that inhibits aminobutyrate aminotransferase activity in vivo, thereby raising the level of gamma-aminobutyric acid in tissues.
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.
Heteromultimers of Kir6 channels (the pore portion) and sulfonylurea receptor (the regulatory portion) which affect function of the HEART; PANCREATIC BETA CELLS; and KIDNEY COLLECTING DUCTS. KATP channel blockers include GLIBENCLAMIDE and mitiglinide whereas openers include CROMAKALIM and minoxidil sulfate.
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.
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).
Inorganic salts of sulfurous acid.
Softening or loss of brain tissue following CEREBRAL INFARCTION; cerebral ischemia (see BRAIN ISCHEMIA), infection, CRANIOCEREBRAL TRAUMA, or other injury. The term is often used during gross pathologic inspection to describe blurred cortical margins and decreased consistency of brain tissue following infarction. Multicystic encephalomalacia refers to the formation of multiple cystic cavities of various sizes in the cerebral cortex of neonates and infants following injury, most notably perinatal hypoxia-ischemic events. (From Davis et al., Textbook of Neuropathology, 2nd ed, p665; J Neuropathol Exp Neurol, 1995 Mar;54(2):268-75)
Inorganic salts of sulfuric acid.
A NADPH-dependent oxidase that reduces hydrogen sulfite to HYDROGEN SULFIDE. It is found in many microoganisms.
An offensive, foul breath odor resulting from a variety of causes such as poor oral hygiene, dental or oral infections, or the ingestion of certain foods.