Loading...
NADPH Dehydrogenase: A flavoprotein that reversibly oxidizes NADPH to NADP and a reduced acceptor. EC 1.6.99.1.NAD(P)H Dehydrogenase (Quinone): A flavoprotein that reversibly catalyzes the oxidation of NADH or NADPH by various quinones and oxidation-reduction dyes. The enzyme is inhibited by dicoumarol, capsaicin, and caffeine.Lamin Type A: A subclass of developmentally regulated lamins having a neutral isoelectric point. They are found to disassociate from nuclear membranes during mitosis.NAD: A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)Quinones: Hydrocarbon rings which contain two ketone moieties in any position. They can be substituted in any position except at the ketone groups.Plastoquinone: Polyunsaturated side-chain quinone derivative which is an important link in the electron transport chain of green plants during the photosynthetic conversion of light energy by photophosphorylation into the potential energy of chemical bonds.Quinone Reductases: NAD(P)H:(quinone acceptor) oxidoreductases. A family that includes three enzymes which are distinguished by their sensitivity to various inhibitors. EC 1.6.99.2 (NAD(P)H DEHYDROGENASE (QUINONE);) is a flavoprotein which reduces various quinones in the presence of NADH or NADPH and is inhibited by dicoumarol. EC 1.6.99.5 (NADH dehydrogenase (quinone)) requires NADH, is inhibited by AMP and 2,4-dinitrophenol but not by dicoumarol or folic acid derivatives. EC 1.6.99.6 (NADPH dehydrogenase (quinone)) requires NADPH and is inhibited by dicoumarol and folic acid derivatives but not by 2,4-dinitrophenol.NADH Dehydrogenase: A flavoprotein and iron sulfur-containing oxidoreductase that catalyzes the oxidation of NADH to NAD. In eukaryotes the enzyme can be found as a component of mitochondrial electron transport complex I. Under experimental conditions the enzyme can use CYTOCHROME C GROUP as the reducing cofactor. The enzyme was formerly listed as EC 1.6.2.1.Thylakoids: Membranous cisternae of the CHLOROPLAST containing photosynthetic pigments, reaction centers, and the electron-transport chain. Each thylakoid consists of a flattened sac of membrane enclosing a narrow intra-thylakoid space (Lackie and Dow, Dictionary of Cell Biology, 2nd ed). Individual thylakoids are interconnected and tend to stack to form aggregates called grana. They are found in cyanobacteria and all plants.L-Lactate Dehydrogenase: A tetrameric enzyme that, along with the coenzyme NAD+, catalyzes the interconversion of LACTATE and PYRUVATE. In vertebrates, genes for three different subunits (LDH-A, LDH-B and LDH-C) exist.Electron Transport: The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)Chloroplasts: Plant cell inclusion bodies that contain the photosynthetic pigment CHLOROPHYLL, which is associated with the membrane of THYLAKOIDS. Chloroplasts occur in cells of leaves and young stems of plants. They are also found in some forms of PHYTOPLANKTON such as HAPTOPHYTA; DINOFLAGELLATES; DIATOMS; and CRYPTOPHYTA.NADP: Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5'-phosphate (NMN) coupled by pyrophosphate linkage to the 5'-phosphate adenosine 2',5'-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed)Alcohol Dehydrogenase: A zinc-containing enzyme which oxidizes primary and secondary alcohols or hemiacetals in the presence of NAD. In alcoholic fermentation, it catalyzes the final step of reducing an aldehyde to an alcohol in the presence of NADH and hydrogen.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).NADH, NADPH Oxidoreductases: A group of oxidoreductases that act on NADH or NADPH. In general, enzymes using NADH or NADPH to reduce a substrate are classified according to the reverse reaction, in which NAD+ or NADP+ is formally regarded as an acceptor. This subclass includes only those enzymes in which some other redox carrier is the acceptor. (Enzyme Nomenclature, 1992, p100) EC 1.6.Glyceraldehyde-3-Phosphate Dehydrogenases: Enzymes that catalyze the dehydrogenation of GLYCERALDEHYDE 3-PHOSPHATE. Several types of glyceraldehyde-3-phosphate-dehydrogenase exist including phosphorylating and non-phosphorylating varieties and ones that transfer hydrogen to NADP and ones that transfer hydrogen to NAD.Rotenone: A botanical insecticide that is an inhibitor of mitochondrial electron transport.Cyanobacteria: 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.Aldehyde Dehydrogenase: An enzyme that oxidizes an aldehyde in the presence of NAD+ and water to an acid and NADH. This enzyme was formerly classified as EC 1.1.1.70.Malate Dehydrogenase: An enzyme that catalyzes the conversion of (S)-malate and NAD+ to oxaloacetate and NADH. EC 1.1.1.37.Photosystem I Protein Complex: A large multisubunit protein complex that is found in the THYLAKOID MEMBRANE. It uses light energy derived from LIGHT-HARVESTING PROTEIN COMPLEXES to drive electron transfer reactions that result in either the reduction of NADP to NADPH or the transport of PROTONS across the membrane.Glucosephosphate DehydrogenaseGlutamate Dehydrogenase: An enzyme that catalyzes the conversion of L-glutamate and water to 2-oxoglutarate and NH3 in the presence of NAD+. (From Enzyme Nomenclature, 1992) EC 1.4.1.2.Isocitrate Dehydrogenase: An enzyme of the oxidoreductase class that catalyzes the conversion of isocitrate and NAD+ to yield 2-ketoglutarate, carbon dioxide, and NADH. It occurs in cell mitochondria. The enzyme requires Mg2+, Mn2+; it is activated by ADP, citrate, and Ca2+, and inhibited by NADH, NADPH, and ATP. The reaction is the key rate-limiting step of the citric acid (tricarboxylic) cycle. (From Dorland, 27th ed) (The NADP+ enzyme is EC 1.1.1.42.) EC 1.1.1.41.Alcohol Oxidoreductases: A subclass of enzymes which includes all dehydrogenases acting on primary and secondary alcohols as well as hemiacetals. They are further classified according to the acceptor which can be NAD+ or NADP+ (subclass 1.1.1), cytochrome (1.1.2), oxygen (1.1.3), quinone (1.1.5), or another acceptor (1.1.99).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)Dihydrolipoamide Dehydrogenase: A flavoprotein containing oxidoreductase that catalyzes the reduction of lipoamide by NADH to yield dihydrolipoamide and NAD+. The enzyme is a component of several MULTIENZYME COMPLEXES.Photosynthetic Reaction Center Complex Proteins: Protein complexes that take part in the process of PHOTOSYNTHESIS. They are located within the THYLAKOID MEMBRANES of plant CHLOROPLASTS and a variety of structures in more primitive organisms. There are two major complexes involved in the photosynthetic process called PHOTOSYSTEM I and PHOTOSYSTEM II.Succinate Dehydrogenase: A flavoprotein containing oxidoreductase that catalyzes the dehydrogenation of SUCCINATE to fumarate. In most eukaryotic organisms this enzyme is a component of mitochondrial electron transport complex II.Carbohydrate Dehydrogenases: Reversibly catalyze the oxidation of a hydroxyl group of carbohydrates to form a keto sugar, aldehyde or lactone. Any acceptor except molecular oxygen is permitted. Includes EC 1.1.1.; EC 1.1.2.; and 1.1.99.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.L-Iditol 2-Dehydrogenase: An alcohol oxidoreductase which catalyzes the oxidation of L-iditol to L-sorbose in the presence of NAD. It also acts on D-glucitol to form D-fructose. It also acts on other closely related sugar alcohols to form the corresponding sugar. EC 1.1.1.14Mitochondria: Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)Arabidopsis Proteins: Proteins that originate from plants species belonging to the genus ARABIDOPSIS. The most intensely studied species of Arabidopsis, Arabidopsis thaliana, is commonly used in laboratory experiments.Arabidopsis: A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.Glycerolphosphate DehydrogenaseGlucose Dehydrogenases: D-Glucose:1-oxidoreductases. Catalyzes the oxidation of D-glucose to D-glucono-gamma-lactone and reduced acceptor. Any acceptor except molecular oxygen is permitted. Includes EC 1.1.1.47; EC 1.1.1.118; EC 1.1.1.119 and EC 1.1.99.10.Aldehyde Oxidoreductases: Oxidoreductases that are specific for ALDEHYDES.Hydroxysteroid Dehydrogenases: Enzymes of the oxidoreductase class that catalyze the dehydrogenation of hydroxysteroids. (From Enzyme Nomenclature, 1992) EC 1.1.-.Glucose 1-Dehydrogenase: A glucose dehydrogenase that catalyzes the oxidation of beta-D-glucose to form D-glucono-1,5-lactone, using NAD as well as NADP as a coenzyme.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Ketoglutarate Dehydrogenase ComplexPQQ Cofactor: A pyrrolo-quinoline having two adjacent keto-groups at the 4 and 5 positions and three acidic carboxyl groups. It is a coenzyme of some DEHYDROGENASES.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.3-Hydroxysteroid Dehydrogenases: Catalyze the oxidation of 3-hydroxysteroids to 3-ketosteroids.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)Phosphogluconate Dehydrogenase: An enzyme of the oxidoreductase class that catalyzes the reaction 6-phospho-D-gluconate and NADP+ to yield D-ribulose 5-phosphate, carbon dioxide, and NADPH. The reaction is a step in the pentose phosphate pathway of glucose metabolism. (From Dorland, 27th ed) EC 1.1.1.43.Sugar Alcohol Dehydrogenases: Reversibly catalyzes the oxidation of a hydroxyl group of sugar alcohols to form a keto sugar, aldehyde or lactone. Any acceptor except molecular oxygen is permitted. Includes EC 1.1.1.; EC 1.1.2. and EC 1.1.99.IMP Dehydrogenase: An enzyme that catalyzes the dehydrogenation of inosine 5'-phosphate to xanthosine 5'-phosphate in the presence of NAD. EC 1.1.1.205.Kinetics: The rate dynamics in chemical or physical systems.Acyl-CoA Dehydrogenases: Enzymes that catalyze the first step in the beta-oxidation of FATTY ACIDS.Formate Dehydrogenases: Flavoproteins that catalyze reversibly the reduction of carbon dioxide to formate. Many compounds can act as acceptors, but the only physiologically active acceptor is NAD. The enzymes are active in the fermentation of sugars and other compounds to carbon dioxide and are the key enzymes in obtaining energy when bacteria are grown on formate as the main carbon source. They have been purified from bovine blood. EC 1.2.1.2.Lactate Dehydrogenases: Alcohol oxidoreductases with substrate specificity for LACTIC ACID.Xanthine Dehydrogenase: An enzyme that catalyzes the oxidation of XANTHINE in the presence of NAD+ to form URIC ACID and NADH. It acts also on a variety of other purines and aldehydes.17-Hydroxysteroid Dehydrogenases: A class of enzymes that catalyzes the oxidation of 17-hydroxysteroids to 17-ketosteroids. EC 1.1.-.Acyl-CoA Dehydrogenase: A flavoprotein oxidoreductase that has specificity for medium-chain fatty acids. It forms a complex with ELECTRON TRANSFERRING FLAVOPROTEINS and conveys reducing equivalents to UBIQUINONE.NAD+ NucleosidaseHydroxybutyrate Dehydrogenase3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide): A ketone oxidoreductase that catalyzes the overall conversion of alpha-keto acids to ACYL-CoA and CO2. The enzyme requires THIAMINE DIPHOSPHATE as a cofactor. Defects in genes that code for subunits of the enzyme are a cause of MAPLE SYRUP URINE DISEASE. The enzyme was formerly classified as EC 1.2.4.3.3-Hydroxyacyl CoA Dehydrogenases: Enzymes that reversibly catalyze the oxidation of a 3-hydroxyacyl CoA to 3-ketoacyl CoA in the presence of NAD. They are key enzymes in the oxidation of fatty acids and in mitochondrial fatty acid synthesis.Ketone Oxidoreductases: Oxidoreductases that are specific for KETONES.Dicumarol: An oral anticoagulant that interferes with the metabolism of vitamin K. It is also used in biochemical experiments as an inhibitor of reductases.Pyruvate Dehydrogenase (Lipoamide): The E1 component of the multienzyme PYRUVATE DEHYDROGENASE COMPLEX. It is composed of 2 alpha subunits (pyruvate dehydrogenase E1 alpha subunit) and 2 beta subunits (pyruvate dehydrogenase E1 beta subunit).Benzoquinones: Benzene rings which contain two ketone moieties in any position. They can be substituted in any position except at the ketone groups.11-beta-Hydroxysteroid Dehydrogenases: Hydroxysteroid dehydrogenases that catalyzes the reversible conversion of CORTISOL to the inactive metabolite CORTISONE. Enzymes in this class can utilize either NAD or NADP as cofactors.Uridine Diphosphate Glucose Dehydrogenase: An enzyme that catalyzes the oxidation of UDPglucose to UDPglucuronate in the presence of NAD+. EC 1.1.1.22.Dihydrouracil Dehydrogenase (NADP): An oxidoreductase involved in pyrimidine base degradation. It catalyzes the catabolism of THYMINE; URACIL and the chemotherapeutic drug, 5-FLUOROURACIL.Indolequinones: INDOLES which have two keto groups forming QUINONES like structures of the indole aromatic ring.Alanine Dehydrogenase: An NAD-dependent enzyme that catalyzes the reversible DEAMINATION of L-ALANINE to PYRUVATE and AMMONIA. The enzyme is needed for growth when ALANINE is the sole CARBON or NITROGEN source. It may also play a role in CELL WALL synthesis because L-ALANINE is an important constituent of the PEPTIDOGLYCAN layer.Glucosephosphate Dehydrogenase Deficiency: A disease-producing enzyme deficiency subject to many variants, some of which cause a deficiency of GLUCOSE-6-PHOSPHATE DEHYDROGENASE activity in erythrocytes, leading to hemolytic anemia.3-alpha-Hydroxysteroid Dehydrogenase (B-Specific): A 3-hydroxysteroid dehydrogenase which catalyzes the reversible reduction of the active androgen, DIHYDROTESTOSTERONE to 5 ALPHA-ANDROSTANE-3 ALPHA,17 BETA-DIOL. It also has activity towards other 3-alpha-hydroxysteroids and on 9-, 11- and 15- hydroxyprostaglandins. The enzyme is B-specific in reference to the orientation of reduced NAD or NADPH.Mannitol Dehydrogenases: Sugar alcohol dehydrogenases that have specificity for MANNITOL. Enzymes in this category are generally classified according to their preference for a specific reducing cofactor.Coenzymes: Small molecules that are required for the catalytic function of ENZYMES. Many VITAMINS are coenzymes.11-beta-Hydroxysteroid Dehydrogenase Type 1: A low-affinity 11 beta-hydroxysteroid dehydrogenase found in a variety of tissues, most notably in LIVER; LUNG; ADIPOSE TISSUE; vascular tissue; OVARY; and the CENTRAL NERVOUS SYSTEM. The enzyme acts reversibly and can use either NAD or NADP as cofactors.Hydroxyprostaglandin Dehydrogenases: Catalyzes reversibly the oxidation of hydroxyl groups of prostaglandins.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.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+)Ubiquinone: A lipid-soluble benzoquinone which is involved in ELECTRON TRANSPORT in mitochondrial preparations. The compound occurs in the majority of aerobic organisms, from bacteria to higher plants and animals.Butyryl-CoA Dehydrogenase: A flavoprotein oxidoreductase that has specificity for short-chain fatty acids. It forms a complex with ELECTRON-TRANSFERRING FLAVOPROTEINS and conveys reducing equivalents to UBIQUINONE.Retinal Dehydrogenase: A metalloflavoprotein enzyme involved the metabolism of VITAMIN A, this enzyme catalyzes the oxidation of RETINAL to RETINOIC ACID, using both NAD+ and FAD coenzymes. It also acts on both the 11-trans- and 13-cis-forms of RETINAL.20-Hydroxysteroid Dehydrogenases: A group of enzymes that catalyze the reversible reduction-oxidation reaction of 20-hydroxysteroids, such as from a 20-ketosteroid to a 20-alpha-hydroxysteroid (EC 1.1.1.149) or to a 20-beta-hydroxysteroid (EC 1.1.1.53).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.Multienzyme Complexes: Systems of enzymes which function sequentially by catalyzing consecutive reactions linked by common metabolic intermediates. They may involve simply a transfer of water molecules or hydrogen atoms and may be associated with large supramolecular structures such as MITOCHONDRIA or RIBOSOMES.11-beta-Hydroxysteroid Dehydrogenase Type 2: An high-affinity, NAD-dependent 11-beta-hydroxysteroid dehydrogenase that acts unidirectionally to catalyze the dehydrogenation of CORTISOL to CORTISONE. It is found predominantly in mineralocorticoid target tissues such as the KIDNEY; COLON; SWEAT GLANDS; and the PLACENTA. Absence of the enzyme leads to a fatal form of childhood hypertension termed, APPARENT MINERALOCORTICOID EXCESS SYNDROME.Naphthoquinones: Naphthalene rings which contain two ketone moieties in any position. They can be substituted in any position except at the ketone groups.Isoenzymes: Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Acyl-CoA Dehydrogenase, Long-Chain: A flavoprotein oxidoreductase that has specificity for long-chain fatty acids. It forms a complex with ELECTRON-TRANSFERRING FLAVOPROTEINS and conveys reducing equivalents to UBIQUINONE.3-Isopropylmalate Dehydrogenase: An NAD+ dependent enzyme that catalyzes the oxidation of 3-carboxy-2-hydroxy-4-methylpentanoate to 3-carboxy-4-methyl-2-oxopentanoate. It is involved in the biosynthesis of VALINE; LEUCINE; and ISOLEUCINE.Homoserine Dehydrogenase: An enzyme that catalyzes the reduction of aspartic beta-semialdehyde to homoserine, which is the branch point in biosynthesis of methionine, lysine, threonine and leucine from aspartic acid. EC 1.1.1.3.Leucine Dehydrogenase: An octameric enzyme belonging to the superfamily of amino acid dehydrogenases. Leucine dehydrogenase catalyzes the reversible oxidative deamination of L-LEUCINE, to 4-methyl-2-oxopentanoate (2-ketoisocaproate) and AMMONIA, with the corresponding reduction of the cofactor NAD+.Isovaleryl-CoA Dehydrogenase: A mitochondrial flavoprotein, this enzyme catalyzes the oxidation of 3-methylbutanoyl-CoA to 3-methylbut-2-enoyl-CoA using FAD as a cofactor. Defects in the enzyme, is associated with isovaleric acidemia (IVA).Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Malate Dehydrogenase (NADP+)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)Phosphoglycerate Dehydrogenase: An enzyme that catalyzes the oxidation of 3-phosphoglycerate to 3-phosphohydroxypyruvate. It takes part in the L-SERINE biosynthesis pathway.Pyruvate Dehydrogenase (Lipoamide)-Phosphatase: (Pyruvate dehydrogenase (lipoamide))-phosphate phosphohydrolase. A mitochondrial enzyme that catalyzes the hydrolytic removal of a phosphate on a specific seryl hydroxyl group of pyruvate dehydrogenase, reactivating the enzyme complex. EC 3.1.3.43.Oxidoreductases Acting on CH-NH Group Donors: Enzymes catalyzing the dehydrogenation of secondary amines, introducing a C=N double bond as the primary reaction. In some cases this is later hydrolyzed.Estradiol Dehydrogenases: Enzymes that catalyze the oxidation of estradiol at the 17-hydroxyl group in the presence of NAD+ or NADP+ to yield estrone and NADH or NADPH. The 17-hydroxyl group can be in the alpha- or beta-configuration. EC 1.1.1.62Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Glutamate Dehydrogenase (NADP+)Succinate-Semialdehyde Dehydrogenase: An enzyme that plays a role in the GLUTAMATE and butanoate metabolism pathways by catalyzing the oxidation of succinate semialdehyde to SUCCINATE using NAD+ as a coenzyme. Deficiency of this enzyme, causes 4-hydroxybutyricaciduria, a rare inborn error in the metabolism of the neurotransmitter 4-aminobutyric acid (GABA).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.Oxidoreductases Acting on CH-CH Group Donors: A subclass of enzymes which includes all dehydrogenases acting on carbon-carbon bonds. This enzyme group includes all the enzymes that introduce double bonds into substrates by direct dehydrogenation of carbon-carbon single bonds.Flavin-Adenine Dinucleotide: A condensation product of riboflavin and adenosine diphosphate. The coenzyme of various aerobic dehydrogenases, e.g., D-amino acid oxidase and L-amino acid oxidase. (Lehninger, Principles of Biochemistry, 1982, p972)Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating): An NAD-dependent glyceraldehyde-3-phosphate dehydrogenase found in the cytosol of eucaryotes. It catalyses the dehydrogenation and phosphorylation of GLYCERALDEHYDE 3-PHOSPHATE to 3-phospho-D-glyceroyl phosphate, which is an important step in the GLYCOLYSIS pathway.Glycerol-3-Phosphate Dehydrogenase (NAD+)Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Prephenate Dehydrogenase: An enzyme that catalyzes the conversion of prephenate to p-hydroxyphenylpyruvate in the presence of NAD. In the enteric bacteria, this enzyme also possesses chorismate mutase activity, thereby catalyzing the first two steps in the biosynthesis of tyrosine. EC 1.3.1.12.PyruvatesCatalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.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.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.HydroquinonesFatty Acids: Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.1-Pyrroline-5-Carboxylate Dehydrogenase: An enzyme that catalyzes the oxidation of 1-pyrroline-5-carboxylate to L-GLUTAMATE in the presence of NAD. Defects in the enzyme are the cause of hyperprolinemia II.Ketoglutaric Acids: A family of compounds containing an oxo group with the general structure of 1,5-pentanedioic acid. (From Lehninger, Principles of Biochemistry, 1982, p442)RNA, Ribosomal, 16S: Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Acetaldehyde: A colorless, flammable liquid used in the manufacture of acetic acid, perfumes, and flavors. It is also an intermediate in the metabolism of alcohol. It has a general narcotic action and also causes irritation of mucous membranes. Large doses may cause death from respiratory paralysis.Aerobiosis: Life or metabolic reactions occurring in an environment containing oxygen.Glutaryl-CoA Dehydrogenase: A flavoprotein enzyme that is responsible for the catabolism of LYSINE; HYDROXYLYSINE; and TRYPTOPHAN. It catalyzes the oxidation of GLUTARYL-CoA to crotonoyl-CoA using FAD as a cofactor. Glutaric aciduria type I is an inborn error of metabolism due to the deficiency of glutaryl-CoA dehydrogenase.Base Composition: The relative amounts of the PURINES and PYRIMIDINES in a nucleic acid.Molecular Weight: The sum of the weight of all the atoms in a molecule.DNA, Ribosomal: DNA sequences encoding RIBOSOMAL RNA and the segments of DNA separating the individual ribosomal RNA genes, referred to as RIBOSOMAL SPACER DNA.20-alpha-Hydroxysteroid Dehydrogenase: An enzymes that catalyzes the reversible reduction-oxidation reaction of 20-alpha-hydroxysteroids, such as from PROGESTERONE to 20-ALPHA-DIHYDROPROGESTERONE.Bacterial Proteins: Proteins found in any species of bacterium.Galactose Dehydrogenases: D-Galactose:NAD(P)+ 1-oxidoreductases. Catalyzes the oxidation of D-galactose in the presence of NAD+ or NADP+ to D-galactono-gamma-lactone and NADH or NADPH. Includes EC 1.1.1.48 and EC 1.1.1.120.Saccharopine Dehydrogenases: Amine oxidoreductases that use either NAD+ (EC 1.5.1.7) or NADP+ (EC 1.5.1.8) as an acceptor to form L-LYSINE or NAD+ (EC 1.5.1.9) or NADP+ (EC 1.5.1.10) as an acceptor to form L-GLUTAMATE. Deficiency of this enzyme causes HYPERLYSINEMIAS.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Betaine-Aldehyde Dehydrogenase: An NAD+ dependent enzyme that catalyzes the oxidation of betain aldehyde to BETAINE.Mitochondria, Liver: Mitochondria in hepatocytes. As in all mitochondria, there are an outer membrane and an inner membrane, together creating two separate mitochondrial compartments: the internal matrix space and a much narrower intermembrane space. In the liver mitochondrion, an estimated 67% of the total mitochondrial proteins is located in the matrix. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p343-4)MalatesSequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Gene Expression Regulation, Enzymologic: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in enzyme synthesis.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Electron Transport Complex II: A flavoprotein oxidase complex that contains iron-sulfur centers. It catalyzes the oxidation of SUCCINATE to fumarate and couples the reaction to the reduction of UBIQUINONE to ubiquinol.Citric Acid Cycle: A series of oxidative reactions in the breakdown of acetyl units derived from GLUCOSE; FATTY ACIDS; or AMINO ACIDS by means of tricarboxylic acid intermediates. The end products are CARBON DIOXIDE, water, and energy in the form of phosphate bonds.Dihydrolipoyllysine-Residue Acetyltransferase: An enzyme that catalyzes the acetyltransferase reaction using ACETYL CoA as an acetyl donor and dihydrolipoamide as acceptor to produce COENZYME A (CoA) and S-acetyldihydrolipoamide. It forms the (E2) subunit of the PYRUVATE DEHYDROGENASE COMPLEX.Dimethylglycine Dehydrogenase: A FLAVOPROTEIN enzyme that catalyzes the oxidative demethylation of dimethylglycine to SARCOSINE and FORMALDEHYDE.Aspartate-Semialdehyde Dehydrogenase: An enzyme that catalyzes the conversion of L-aspartate 4-semialdehyde, orthophosphate, and NADP+ to yield L-4-aspartyl phosphate and NADPH. EC 1.2.1.11.Flavins: Derivatives of the dimethylisoalloxazine (7,8-dimethylbenzo[g]pteridine-2,4(3H,10H)-dione) skeleton. Flavin derivatives serve an electron transfer function as ENZYME COFACTORS in FLAVOPROTEINS.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Enzyme Stability: The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.Aldehydes: Organic compounds containing a carbonyl group in the form -CHO.IsocitratesVitamin K: A lipid cofactor that is required for normal blood clotting. Several forms of vitamin K have been identified: VITAMIN K 1 (phytomenadione) derived from plants, VITAMIN K 2 (menaquinone) from bacteria, and synthetic naphthoquinone provitamins, VITAMIN K 3 (menadione). Vitamin K 3 provitamins, after being alkylated in vivo, exhibit the antifibrinolytic activity of vitamin K. Green leafy vegetables, liver, cheese, butter, and egg yolk are good sources of vitamin K.Pseudomonas: A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.Aziridines: Saturated azacyclopropane compounds. They include compounds with substitutions on CARBON or NITROGEN atoms.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)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).Enzyme Induction: An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.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.Genes, Bacterial: The functional hereditary units of BACTERIA.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Electron Spin Resonance Spectroscopy: A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.Cortisone Reductase: An enzyme that catalyzes the interconversion of a ketone and hydroxy group at C-20 of cortisone and other 17,20,21-trihydroxy steroids. EC 1.1.1.53.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Succinates: Derivatives of SUCCINIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a 1,4-carboxy terminated aliphatic structure.Pyruvate Dehydrogenase Complex Deficiency Disease: An inherited metabolic disorder caused by deficient enzyme activity in the PYRUVATE DEHYDROGENASE COMPLEX, resulting in deficiency of acetyl CoA and reduced synthesis of acetylcholine. Two clinical forms are recognized: neonatal and juvenile. The neonatal form is a relatively common cause of lactic acidosis in the first weeks of life and may also feature an erythematous rash. The juvenile form presents with lactic acidosis, alopecia, intermittent ATAXIA; SEIZURES; and an erythematous rash. (From J Inherit Metab Dis 1996;19(4):452-62) Autosomal recessive and X-linked forms are caused by mutations in the genes for the three different enzyme components of this multisubunit pyruvate dehydrogenase complex. One of the mutations at Xp22.2-p22.1 in the gene for the E1 alpha component of the complex leads to LEIGH DISEASE.Methanol: A colorless, flammable liquid used in the manufacture of FORMALDEHYDE and ACETIC ACID, in chemical synthesis, antifreeze, and as a solvent. Ingestion of methanol is toxic and may cause blindness.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Formates: Derivatives of formic acids. Included under this heading are a broad variety of acid forms, salts, esters, and amides that are formed with a single carbon carboxy group.Chemistry: A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.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.Spectrophotometry, Ultraviolet: Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Proline Oxidase: The first enzyme of the proline degradative pathway. It catalyzes the oxidation of proline to pyrroline-5-carboxylic acid in the presence of oxygen and water. The action is not reversible. The specific activity of proline oxidase increases with age. EC 1.5.3.-.Methylmalonate-Semialdehyde Dehydrogenase (Acylating): An enzyme that plays a role in the VALINE; LEUCINE; and ISOLEUCINE catabolic pathways by catalyzing the oxidation of 2-methyl-3-oxopropanate to propanoyl-CoA using NAD+ as a coenzyme. Methylmalonate semialdehyde dehydrogenase deficiency is characterized by elevated BETA-ALANINE and 3-hydropropionic acid.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.Electron Transport Complex I: A flavoprotein and iron sulfur-containing oxidoreductase complex that catalyzes the conversion of UBIQUINONE to ubiquinol. In MITOCHONDRIA the complex also couples its reaction to the transport of PROTONS across the internal mitochondrial membrane. The NADH DEHYDROGENASE component of the complex can be isolated and is listed as EC 1.6.99.3.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Species Specificity: 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.Chemical Phenomena: The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Flavin Mononucleotide: A coenzyme for a number of oxidative enzymes including NADH DEHYDROGENASE. It is the principal form in which RIBOFLAVIN is found in cells and tissues.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Succinic Acid: A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawley's Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851)Cytosol: Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.FlavoproteinsStructure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Ethanol: A clear, colorless liquid rapidly absorbed from the gastrointestinal tract and distributed throughout the body. It has bactericidal activity and is used often as a topical disinfectant. It is widely used as a solvent and preservative in pharmaceutical preparations as well as serving as the primary ingredient in ALCOHOLIC BEVERAGES.Thioctic Acid: An octanoic acid bridged with two sulfurs so that it is sometimes also called a pentanoic acid in some naming schemes. It is biosynthesized by cleavage of LINOLEIC ACID and is a coenzyme of oxoglutarate dehydrogenase (KETOGLUTARATE DEHYDROGENASE COMPLEX). It is used in DIETARY SUPPLEMENTS.Alcohols: Alkyl compounds containing a hydroxyl group. They are classified according to relation of the carbon atom: primary alcohols, R-CH2OH; secondary alcohols, R2-CHOH; tertiary alcohols, R3-COH. (From Grant & Hackh's Chemical Dictionary, 5th ed)GlutaratesMitochondria, Heart: The mitochondria of the myocardium.Citrate (si)-Synthase: Enzyme that catalyzes the first step of the tricarboxylic acid cycle (CITRIC ACID CYCLE). It catalyzes the reaction of oxaloacetate and acetyl CoA to form citrate and coenzyme A. This enzyme was formerly listed as EC 4.1.3.7.Amino Acid Oxidoreductases: A class of enzymes that catalyze oxidation-reduction reactions of amino acids.Aspartokinase Homoserine Dehydrogenase: A bifunctional protein consisting of aspartokinase, and homoserine dehydrogenase activities. It is found primarily in BACTERIA and in PLANTS.Disulfiram: A carbamate derivative used as an alcohol deterrent. It is a relatively nontoxic substance when administered alone, but markedly alters the intermediary metabolism of alcohol. When alcohol is ingested after administration of disulfiram, blood acetaldehyde concentrations are increased, followed by flushing, systemic vasodilation, respiratory difficulties, nausea, hypotension, and other symptoms (acetaldehyde syndrome). It acts by inhibiting aldehyde dehydrogenase.GluconatesChromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.Benzaldehyde Dehydrogenase (NADP+)Hydroxyquinolines: The 8-hydroxy derivatives inhibit various enzymes and their halogenated derivatives, though neurotoxic, are used as topical anti-infective agents, among other uses.Oxygen Consumption: The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)Acetoin Dehydrogenase: An enzyme that catalyzes the conversion of acetoin to diacetyl in the presence of NAD.Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Rhodobacter sphaeroides: Spherical phototrophic bacteria found in mud and stagnant water exposed to light.