Evidence that the mitochondrial activator of phosphorylated branched-chain 2-oxoacid dehydrogenase complex is the dissociated E1 component of the complex.
Branched-chain 2-oxoacid dehydrogenase complex is inactivated by phosphorylation of the alpha-subunit of the E1 component of the complex. High-speed supernatant from rat liver mitochondria contains an activator protein which can restore activity to the phosphorylated complex without concomitant dephosphorylation [(1982) FEBS Lett. 147, 35-39]. We report here several lines of evidence which indicate that activator is the dissociated non-phosphorylated form of the E1 component.
D042942:3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide); D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002417:Cattle; D007658:Ketone Oxidoreductases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D007672:Kidney Cortex / Q000201:enzymology; D046911:Macromolecular Substances; D008928:Mitochondria / Q000201:enzymology*; D008929:Mitochondria, Heart / Q000201:enzymology; D008930:Mitochondria, Liver / Q000201:enzymology; D009097:Multienzyme Complexes / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D013835:Thiamine Pyrophosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D014018:Tissue Distribution; D014461:Ultracentrifugation
D046911:Macromolecular Substances; D009097:Multienzyme Complexes; C033041:thiamine thiothiazolone pyrophosphate; D000255:Adenosine Triphosphate; D007658:Ketone Oxidoreductases; D042942:3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide); D011494:Protein Kinases; C035627:(3-methyl-2-oxobutanoate dehydrogenase (lipoamide)) kinase; D013835:Thiamine Pyrophosphate