Vancomycin inhibits peptidoglycan synthesis primarily by which of the following molecular interactions?

• A. Forming pores in the inner membrane which cause dissipation of proton motive force and indirectly inhibit peptidoglycan polymerase activity due to collapse of energy-dependent transport systems.
• B. Acting as a competitive substrate for MurA enzyme, thereby increasing the turnover of UDP-N-acetylmuramic acid and causing depletion of cytoplasmic precursors that stops peptidoglycan synthesis.
• C. Binding tightly to the D-Ala-D-Ala terminus of peptidoglycan precursors, blocking transglycosylation and preventing incorporation of subunits into the growing cell wall.
• D. Chelating divalent cations in the periplasm that are essential cofactors for penicillin-binding proteins, thereby preventing all PBP-catalyzed reactions including transpeptidation.

Answer: (C)