Reaction: pyruvate + [dihydrolipoyllysine-residue acetyltransferase] lipoyllysine = [dihydrolipoyllysine-residue acetyltransferase] S-acetyldihydrolipoyllysine + CO2
For diagram of reaction click here.
Glossary: dihydrolipoyl group
thiamine diphosphate
Other name(s): pyruvate decarboxylase (ambiguous); pyruvate dehydrogenase (ambiguous); pyruvate dehydrogenase (lipoamide); pyruvate:lipoamide 2-oxidoreductase (decarboxylating and acceptor-acetylating); pyruvic acid dehydrogenase; pyruvic dehydrogenase (ambiguous)
Systematic name: pyruvate:[dihydrolipoyllysine-residue acetyltransferase]-lipoyllysine 2-oxidoreductase (decarboxylating, acceptor-acetylating)
Comments: Contains thiamine diphosphate. It is a component (in multiple copies) of the multienzyme pyruvate dehydrogenase complex, EC 1.2.1.104, in which it is bound to a core of molecules of EC 2.3.1.12, dihydrolipoyllysine-residue acetyltransferase, which also binds multiple copies of EC 1.8.1.4, dihydrolipoyl dehydrogenase. It does not act on free lipoamide or lipoyllysine, but only on the lipoyllysine residue in EC 2.3.1.12.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9014-20-4
References:
1. Ochoa, S. Enzymic mechanisms in the citric acid cycle. Adv. Enzymol. Relat. Subj. Biochem. 15 (1954) 183-270.
2. Scriba, P. and Holzer, H. Gewinnung von αHydroxyäthyl-2-thiaminpyrophosphat mit Pyruvatoxydase aus Schweineherzmuskel. Biochem. Z. 334 (1961) 473-486.
3. Perham, R.N. Swinging arms and swinging domains in multifunctional enzymes: catalytic machines for multistep reactions. Annu. Rev. Biochem., 69, (2000) 961-1004. [PMID: 10966480]