Fig. 2

Subunit organization schematic of PDHc, OGDHc and FAS. On top, organization of the different proteins comprising the pyruvate dehydrogenase complex (PDHc) is shown. The flexible linkers connecting the lipoyl domains allow for easier transfer of substrates among the E1p, E2p and E3 subunits needed for the creation of ACoA. E2p: dihydrolipoyl acetyltransferase, E3BP: E3 Binding Protein, C: core domain, PSBD: peripheral subunit binding domain, E1p: pyruvate dehydrogenase (lipoamide), E3: dihydrolipoyl dehydrogenase, L: lipoyl domain. In the middle, organization of the 2-oxoglutarate dehydrogenase complex (OGDHc) is shown. The disordered flexible arms holding the lipoyl domains facilitate the substrate channeling among the core E2o proteins and the peripheral E1o and E3 subunits. E1o: 2-oxoglutarate decarboxylase, E2o: dihydrolipoyl succinyltransferase, E3: dihydrolipoyl dehydrogenase, L: lipoyl domain. On the bottom, subunit organization of the fatty acid synthase (FAS) is shown. The acyl-carrier protein (ACP) is linked to the thioesterase (TE) domain through a flexible disordered arm that allows access to the covalently connected substrate to multiple subunits with different activities needed for de novo lipogenesis. TE: thioesterase, KR: β-ketoacyl reductase, ER: β-enoyl reductase, DH: dehydratase, MAT: malonyl−/acetyl-CoA-ACP-transacylase, KS: β-ketoacyl synthase, ACP: Acyl- Carrier Protein, Substr.: Substrate