Pyruvate Dehydrogenase

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Pyruvate Dehydrogenase


a polyenzymatic complex that catalyzes the oxidative decarboxylation of pyruvic acid:

This reaction is the main pathway for the conversion of alpha keto acids in the tissues of animals, plants, and aerobic microorganisms; it links the two most important metabolic processes— glycolysis and the reactions of the tricarboxylic acid cycle. The vitamin derivatives thiamine pyrophosphate (TPP), coenzyme A (CoA), flavine-adenine dinucleotide (FAD), nicotinamide-adenine dinucleotide (NAD), lipoic acid, and Mg2+ ions all take part in the catalytic activity of pyruvate dehydrogenase. Magnesium ions are also necessary cofactors of the enzymes pyruvate decarboxylase, lipoyl transacetylase, and lipoyl dehydrogenase. The enzymes are present in specific quantitative relationships and fix the structure of the enzyme complex, which does not dissociate under normal conditions.

Pyruvate dehydrogenase that is extracted from animal organs and bacteria is a large protein aggregate with a molecular weight that ranges from 4,800,000 to 10,000,000 depending on its source. The complex ranges in size from 300 to 400 angstroms and is regulated by a variety of factors. In living organisms, pyruvate dehydrogenase is inhibited by phosphorylation of the decarboxylase component and reactivated upon splitting of the phosphate radical; the activity is also dependent on the energetic and hormonal state of the organism.


Glemzha, A. A. “Piruvatdegidrogenaza: mekhanizm deistviia i struktura.” In the collection Uspekhi biologicheskoi khimii. Moscow, 1969.


References in periodicals archive ?
Therapeutic potential of dichloroacetate for pyruvate dehydrogenase complex deficiency.
Evidence for existence of tissue-specific regulation of the mammalian pyruvate dehydrogenase complex.
3] Nonstandard abbreviations: MEGS, mitochondrial energy-generating system; PDHc, pyruvate dehydrogenase complex; TCA, tricarboxylic acid; OXPHOS, oxidative phosphorylation; RC, respiratory chain; ANT, adenine nucleotide translocator; mtDNA, mitochondrial DNA; CCCP, carbonyl cyanide 3-chlorophenyl hydrazone; CS, citrate synthase; SDH, succinate dehydrogenase; CrP, phosphocreatine; 2-ODHc, 2-oxoglutarate dehydrogenase complex; and SCC, succinate cytochrome c oxidoreductase (complex II + III).
Enzyme inhibitory autoantibodies to pyruvate dehydrogenase complex in primary biliary cirrhosis: applications of a semi-automated assay.
Investigations for defects in the electron transport chain and the pyruvate dehydrogenase complex (such as assay of electron transport chain function in muscle and pyruvate dehydrogenase activity in skin fibroblasts, and molecular biology studies of mitochondrial DNA) are invasive, time-consuming, and expensive.
The nair, schizophrenic, autistic and civilisational disease group had features of Neanderthal metabolism as indicated by pyruvate dehydrogenase suppression.
Zellweger's spectrum) Plasma lactate / 1 ml fluoride blood on A normal lactate / pyruvate ratio ice to reach laboratory pyruvate ratio [less immediately or blood than or equal to]20 collected in obtained during lactic pre-prepared perchloric acidosis suggests acid tube pyruvate dehydrogenase deficiency or a gluconeogenic defect Specific tissue or Plasma, leukocytes, Confirmation of plasma enzyme assays erythrocytes, skin specific enzyme fibroblasts or deficiency hepatocytes collected as per testing laboratory protocol Molecular gene 1 ml EDTA blood for Confirmation of genetic sequencing or nuclear gene mutations.
Primer sequences for acetyl-CoA acyltransferase (ACAA2), long-chain acyl-CoA dehydrogenase (ACADL), acyl-CoA synthetase (ACSL1), very long chain acyl-CoA dehydrogenase (ACADVL), carnitine palmitoyltransferase 1B (CPT1B), enoyl-CoA hydratase (ECH1), hydroxyacyl-CoA dehydrogenase (HADHA), pyruvate dehydrogenase kinase (PDK4), PGC-1[alpha], PGC-1[beta], PPAR[alpha], glutamate dehydrogenase, and 18S ribosomal RNA are available in Supplemental Material, Table S1 (http://dx.
Increased blood lactate concentrations may also, especially in patients with sepsis, result from impaired clearance of lactate (4), inhibition of pyruvate dehydrogenase (5) and accelerated aerobic glycolysis6, at least in part related to activation of Na/K ATPase by endogenous or exogenous catecholamines (7,8).
No effect of trimetazidine was observed on glycolysis, glucose oxidation, fatty acid oxidation, or active pyruvate dehydrogenase when palmitate was substituted with 0.
Pyruvate dehydrogenase kinase 1 (PDK-1) phosphorylates the enzyme pyruvate dehydrogenase to inhibit its activity.