Premium
Essential role of coenzyme A in pyruvate dehydrogenase kinase activity
Author(s) -
Siess E.A.,
Weiland O.H.
Publication year - 1982
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(82)80808-9
Subject(s) - pyruvate dehydrogenase kinase , pyruvate dehydrogenase complex , coenzyme a , dithiothreitol , biochemistry , pyruvate decarboxylation , pyruvate dehydrogenase phosphatase , pyruvate kinase , cofactor , chemistry , thiol , oxoglutarate dehydrogenase complex , dehydrogenase , dihydrolipoyl transacetylase , enzyme , glutathione , glycolysis , reductase
The rate of phosphorylation and concomitant inactivation of purified pig heart muscle pyruvate dehydrogenase complex by intrinsic kinase (EC 2.7.1.99) is markedly accelerated by the addition of coenzyme A to the incubation medium, showing a half‐maximum effect at 1.8 μM. The pantetheine moiety is the effective part of the coenzyme A molecule. The free thiol group is prerequisite for the stimulatory action, acetyl‐CoA, benzoyl‐CoA or CoAS‐SCoA being ineffectual. The thiol's specificity is evidenced by showing that dithiothreitol, 2‐mercaptoethanol or glutathione up to 5 mM failed to replace coenzyme A. The possibility is considered that coenzyme A might act as a physiological modifier of pyruvate dehydrogenase kinase activity.