The Ketoglutarate Dehydrogenase Complex is a multi-enzyme complex involved in the citric acid cycle, catalyzing the oxidative decarboxylation of alpha-ketoglutarate to succinyl-CoA and CO2, thereby connecting the catabolism of amino acids, carbohydrates, and fats to the generation of energy in the form of ATP.
A multienzyme complex responsible for the formation of ACETYL COENZYME A from pyruvate. The enzyme components are PYRUVATE DEHYDROGENASE (LIPOAMIDE); dihydrolipoamide acetyltransferase; and LIPOAMIDE DEHYDROGENASE. Pyruvate dehydrogenase complex is subject to three types of control: inhibited by acetyl-CoA and NADH; influenced by the energy state of the cell; and inhibited when a specific serine residue in the pyruvate decarboxylase is phosphorylated by ATP. PYRUVATE DEHYDROGENASE (LIPOAMIDE)-PHOSPHATASE catalyzes reactivation of the complex. (From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed)
A family of compounds containing an oxo group with the general structure of 1,5-pentanedioic acid. (From Lehninger, Principles of Biochemistry, 1982, p442)
Oxidoreductases that are specific for KETONES.
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.
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.
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.
'Keto acids', also known as ketone bodies, are water-soluble compounds - acetoacetic acid, beta-hydroxybutyric acid, and acetone - that are produced during fat metabolism when liver glycogen stores are depleted, providing an alternative energy source for the brain and other organs in states of carbohydrate restriction or intense physical exertion.
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).
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.
An enzyme that catalyzes the transfer of UMP from UDPglucose to galactose 1-phosphate, forming UDPgalactose and glucose 1-phosphate. Deficiency in this enzyme is the major cause of GALACTOSEMIA. EC 2.7.7.12.
A subclass of enzymes of the transferase class that catalyze the transfer of an amino group from a donor (generally an amino acid) to an acceptor (generally a 2-keto acid). Most of these enzymes are pyridoxyl phosphate proteins. (Dorland, 28th ed) EC 2.6.1.
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.
Derivatives of OXALOACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that include a 2-keto-1,4-carboxy aliphatic structure.
Coenzyme A is an essential coenzyme that plays a crucial role in various metabolic processes, particularly in the transfer and activation of acetyl groups in important biochemical reactions such as fatty acid synthesis and oxidation, and the citric acid cycle.
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.
An amino acid produced in the urea cycle by the splitting off of urea from arginine.
Glutarates are organic compounds, specifically carboxylic acids, that contain a five-carbon chain with two terminal carboxyl groups and a central methyl group, playing a role in various metabolic processes, including the breakdown of certain amino acids. They can also refer to their salts or esters. Please note that this definition is concise and may not cover all aspects of glutarates in depth.
The coenzyme form of Vitamin B1 present in many animal tissues. It is a required intermediate in the PYRUVATE DEHYDROGENASE COMPLEX and the KETOGLUTARATE DEHYDROGENASE COMPLEX.
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.
A family of signal transducing adaptor proteins that control the METABOLISM of NITROGEN. They are primarily found in prokaryotes.
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.
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.
The rate dynamics in chemical or physical systems.