Amphomycin inhibits phospho-N-acetylmuramyl-pentapeptide translocase in peptidoglycan synthesis of Bacillus.

Amphomycin, a selective inhibitor of peptidoglycan synthesis of bacteria, inhibited the lipid intermediates accumulation and the peptidoglycan synthesis from UDP-N-acetylmuramyl-L-Ala-D-Glu-³H]-meso-Dpm-D-Ala-D-Ala (UDP-MurNAc-pentapeptide) and UDP-N-acetylglucosamine (UDP-GlcNAc) with a particulate fraction from $\text{Bacillus}\text{megaterium}$ KM, and also inhibited the formation of MurNAc (-pentapeptide)-P-P-lipid in the absence of UDP-GlcNAc. But it did not inhibit the formation of peptidoglycan from MurNAc(-pentapeptide)-P-P-lipid and UDP-GlcNAc with the same system of the organism.Thus, it is concluded that the site of action of amphomycin is phospho-MurNAc-pentapeptide translocase in peptidoglycan synthesis.