Biotin protein ligase (EC 6.3.4.15) catalyzes the synthesis of an activated form of biotin, biotinyl-5'-AMP, from substrates biotin and ATP followed by biotinylation of the biotin carboxyl carrier protein subunit of acetyl-CoA carboxylase. Biotin protein ligase (BPL) is the enzyme responsible for attaching biotin to a specific lysine at the active site of biotin enzymes. Biotin attachment is a two step reaction that results in the formation of an amide linkage between the carboxyl group of biotin and the epsilon-amino group of the modified lysine.
Jiyao W et al.(2023). "The conserved domain database in 2023.",