Aminopyrine
Aminopyrine N-Demethylase
Sterol 14-Demethylase
An NADPH-dependent P450 enzyme that plays an essential role in the sterol biosynthetic pathway by catalyzing the demethylation of 14-methyl sterols such as lanosterol. The enzyme acts via the repeated hydroxylation of the 14-methyl group, resulting in its stepwise conversion into an alcohol, an aldehyde and then a carboxylate, which is removed as formic acid. Sterol 14-demethylase is an unusual cytochrome P450 enzyme in that it is found in a broad variety of organisms including ANIMALS; PLANTS; FUNGI; and protozoa.
Histone Demethylases
Jumonji Domain-Containing Histone Demethylases
Oxidoreductases, N-Demethylating
Aniline Hydroxylase
Parietal Cells, Gastric
Microsomes, Liver
Retinoblastoma-Binding Protein 2
Cytochrome P-450 Enzyme System
A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.
Methylation
Histones
Oxidoreductases, O-Demethylating
Antipyrine
Dipyrone
Dealkylation
Phenobarbital
Peroxides
A group of compounds that contain a bivalent O-O group, i.e., the oxygen atoms are univalent. They can either be inorganic or organic in nature. Such compounds release atomic (nascent) oxygen readily. Thus they are strong oxidizing agents and fire hazards when in contact with combustible materials, especially under high-temperature conditions. The chief industrial uses of peroxides are as oxidizing agents, bleaching agents, and initiators of polymerization. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Pyrazolones
Lanosterol
Secobarbital
NADPH-Ferrihemoprotein Reductase
Seminal Vesicles
Microsomes
Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Histone-Lysine N-Methyltransferase
Mixed Function Oxygenases
Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.
Gastric Mucosa
Lining of the STOMACH, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. The surface cells produce MUCUS that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the LAMINA PROPRIA at various region of the stomach (CARDIA; GASTRIC FUNDUS; and PYLORUS), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, HYDROCHLORIC ACID, or hormones.
Epigenesis, Genetic
A genetic process by which the adult organism is realized via mechanisms that lead to the restriction in the possible fates of cells, eventually leading to their differentiated state. Mechanisms involved cause heritable changes to cells without changes to DNA sequence such as DNA METHYLATION; HISTONE modification; DNA REPLICATION TIMING; NUCLEOSOME positioning; and heterochromatization which result in selective gene expression or repression.
Liver
Histamine
Rats, Inbred Strains
Aniline Compounds
Semicarbazides
Vanillic Acid
F-Box Proteins
A family of proteins that share the F-BOX MOTIF and are involved in protein-protein interactions. They play an important role in process of protein ubiquition by associating with a variety of substrates and then associating into SCF UBIQUITIN LIGASE complexes. They are held in the ubiquitin-ligase complex via binding to SKP DOMAIN PROTEINS.
Benzphetamine
Cytochrome Reductases
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)
Enzyme Induction
Tranylcypromine
A propylamine formed from the cyclization of the side chain of amphetamine. This monoamine oxidase inhibitor is effective in the treatment of major depression, dysthymic disorder, and atypical depression. It also is useful in panic and phobic disorders. (From AMA Drug Evaluations Annual, 1994, p311)
Sulfonium Compounds
Anemia, Pernicious
A megaloblastic anemia occurring in children but more commonly in later life, characterized by histamine-fast achlorhydria, in which the laboratory and clinical manifestations are based on malabsorption of vitamin B 12 due to a failure of the gastric mucosa to secrete adequate and potent intrinsic factor. (Dorland, 27th ed)
Lipid Peroxides
Peroxides produced in the presence of a free radical by the oxidation of unsaturated fatty acids in the cell in the presence of molecular oxygen. The formation of lipid peroxides results in the destruction of the original lipid leading to the loss of integrity of the membranes. They therefore cause a variety of toxic effects in vivo and their formation is considered a pathological process in biological systems. Their formation can be inhibited by antioxidants, such as vitamin E, structural separation or low oxygen tension.