BACITRACIN: AN INHIBITOR OF THE DEPHOSPHORYLATION OF LIPID PYROPHOSPHATE, AN INTERMEDIATE IN THE BIOSYNTHESIS OF THE PEPTIDOGLYCAN OF BACTERIAL CELL WALLS

Abstract

Bracitracin inhibits bacterial cell wall synthesis and induces an accumulation of UDP-acetylmuramyl-pentapeptide in growing cells of Staphylococcus aureus. With particulate enzymes which catalyze peptidoglycan synthesis, in the presence of bacitracin disaccharide (-pentapeptide)-P-P-lipid, an intermediate in cell wall synthesis, was utilized to form peptidoglycan without the liberation of inorganic phosphate. A lipid, assumed to be lipid- P-P, accumulated, whose dephosphorylation was specifically inhibited by bacitracin. Bacitracin, therefore, inhibits peptidoglycan synthesis by preventing the lipid carrier from re-entering the reaction cycle of cell wall synthesis.