Lipoate-protein ligase A (LplA) catalyzes the formation of an amide linkage between free lipoic acid and a specific lysine residue of the lipoyl domain in lipoate dependent enzymes, similar to the biotinylation reaction mediated by biotinyl protein ligase (BPL). The two step reaction includes activation of exogenously supplied lipoic acid at the expense of ATP to lipoyl-AMP and then transfer to the epsilon-amino group of a specific lysine residue of the lipoyl domain of the target protein.
Jiyao W et al.(2023). "The conserved domain database in 2023.",