The branched-chain alpha-keto dehydrogenase complex catalyzes the overall conversion of alpha-keto acids to acyl-CoA and CO(2). It contains multiple copies of three enzymatic components: branched-chain alpha-keto acid decarboxylase (E1), lipoamide acyltransferase (E2) and lipoamide dehydrogenase (E3).
Involvement in disease
Defects in BCKDHB are the cause of maple syrup urine disease type IB (MSUD1B) [MIM:248600]. MSUD is an autosomal recessive disorder characterized by mental and physical retardation, feeding problems, and a maple syrup odor to the urine.