Identification of functional amino acids in the macrolide 2'- phosphotransferase II

Abstract

Macrolide 2'-phosphotransferase [MPH(2')] transfers the γ phosphate of ATP to the 2'-OH group of macrolide antibiotics. The role of aspartic acids in the putative ATP-binding site of MPH(2')II was investigated through the substitution of alanine for aspartate by site-directed mutagenesis. D200A, D209A, D219A, and D231A mutant strains were unable to inactivate the substrate oleandomycin, while a D227A mutant retained 7% of the activity of the original enzyme.