InterPro domain: IPR004562

Lipoic acid is an essential cofactor of the alpha-ketoacid dehydrogenase complexes and the glycine cleavage system. It is covalently attached to a specific lysine residue of the subunit of the complexes.

In mammals, covalent attachment of lipoic acid to the proteins occurs in two successive reactions. First, lipoic acid is activated to lipoyl-AMP by lipoate-activating enzyme, and then the lipoyl moiety is transferred to apoproteins by the action of lipoyltransferase [ 1 , 2 ]. In contrast, in Escherichia coli, lipoate-protein ligase A catalyses both the activation and the transfer of lipoate [ 3 ]. This entry includes lipoyltransferases and lipoate-protein ligases.

1. Crystal structure of bovine lipoyltransferase in complex with lipoyl-AMP. J. Mol. Biol. 371, 222-34
2. Purification and characterization of lipoyl-AMP:N epsilon-lysine lipoyltransferase from bovine liver mitochondria. J. Biol. Chem. 269, 16605-9
3. Identification of the gene encoding lipoate-protein ligase A of Escherichia coli. Molecular cloning and characterization of the lplA gene and gene product. J. Biol. Chem. 269, 16091-100