- The biotin domain peptide from the biotin carboxyl carrier protein of Escherichia coli acetyl-CoA carboxylase causes a marked increase in the catalytic efficiency of biotin carboxylase and carboxyltransferase relative to free biotin. Blanchard, C.Z., Chapman-Smith, A., Wallace, J.C., Waldrop, G.L. J. Biol. Chem. (1999)