Activation of the branched-chain α-ketoacid dehydrogenase complex by a broad specificity protein phosphatase

Robert Harris, Ralph Paxton, Rex A. Parker

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

A broad-specificity protein phosphatase, purified from rat liver, can be used to activate the phosphorylated (inactive) branched-chain α-ketoacid dehydrogenase complex of crude tissue extracts. This enables estimation of the proportion of active (unphosphorylated) complex in a given tissue under different physiological states. Practically all (95 percent) of the complex was found in the active form in rat hearts perfused with leucine as the only oxidizable substrate. In contrast, only 13 percent of the complex was found in the active form when the perfusion medium was supplemented with glucose plus insulin. These findings are consistent with previously measured flux rates through the complex in perfused rat hearts.

Original languageEnglish
Pages (from-to)1497-1503
Number of pages7
JournalBiochemical and Biophysical Research Communications
Volume107
Issue number4
DOIs
StatePublished - Aug 31 1982

Fingerprint

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)
Phosphoprotein Phosphatases
Rats
Chemical activation
Tissue Extracts
Complex Mixtures
Leucine
Liver
Perfusion
Insulin
Tissue
Fluxes
Glucose
Substrates

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Molecular Biology

Cite this

Activation of the branched-chain α-ketoacid dehydrogenase complex by a broad specificity protein phosphatase. / Harris, Robert; Paxton, Ralph; Parker, Rex A.

In: Biochemical and Biophysical Research Communications, Vol. 107, No. 4, 31.08.1982, p. 1497-1503.

Research output: Contribution to journalArticle

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