Studies on bacterial cell wall inhibitors. VIII. Mode of action of a new antibiotic, azureomycin B, in Bacillus cereus T.
Azureomycin B, a new antibiotic which contains sugar, amino acid and phenol moieties and inhibits Gram-positive bacteria, was found to be a specific inhibitor of peptidoglycan synthesis in bacteria. The antibiotic lysed growing cells of Bacillus cereus T at a concentration of 10 micrograms/ml but did not affect resting cells. Microscopical observation revealed swelling and lysis of the bacterial rods when treated with azureomycin B. The incorporation of [3H]diaminopimelic acid or [14C]glucosamine into acid-insoluble fraction of growing cells of Bacillus cereus T was strongly inhibited in the presence of azureomycin B, but that of [14C]leucine, [3H]thymidine or [3H]uridine were not, at least until 5 minutes after the beginning of the incubation. The antibiotic caused accumulation of a nucleotide precursor in the cells which was identified as UDP-MurNAc-L-Ala-D-Glu-meso-Dpm-D-Ala-D-Ala. Thus the site of action was suggested to lie between this nucleotide and peptidoglycan in the pathway of peptidoglycan synthesis.
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001409:Bacillus cereus / Q000187:drug effects* / Q000648:ultrastructure; D002473:Cell Wall / Q000378:metabolism; D003960:Diaminopimelic Acid / Q000378:metabolism; D005944:Glucosamine / Q000378:metabolism; D007930:Leucine / Q000378:metabolism; D009711:Nucleotides / Q000378:metabolism; D010457:Peptidoglycan / Q000096:biosynthesis; D013936:Thymidine / Q000378:metabolism; D014529:Uridine / Q000378:metabolism
D000900:Anti-Bacterial Agents; D009711:Nucleotides; D010457:Peptidoglycan; D003960:Diaminopimelic Acid; D007930:Leucine; D005944:Glucosamine; D013936:Thymidine; D014529:Uridine