The 2-oxoglutarate dehydrogenase complex catalyzes the overall conversion of 2-oxoglutarate to succinyl-CoA and CO(2). It contains multiple copies of 3 enzymatic components: 2-oxoglutarate dehydrogenase (E1), dihydrolipoamide succinyltransferase (E2) and lipoamide dehydrogenase (E3). Forms a 24-polypeptide structural core with octahedral symmetry. Belongs to the 2-oxoacid dehydrogenase family. Note: This description may include information from UniProtKB.