Escherichia coli susceptible to glycopeptide antibiotics.

摘要: Mutants of Escherichia coli susceptible to vancomycin were isolated after mutagenesis with nitrosoguanidine. One such mutant was studied extensively. Multiple regression analysis the relationship between physical properties 20 glycopeptides and their in vitro activities against vancomycin-susceptible revealed a significant correlation molecular mass (P = 0.007). pI, hydrophobicity, affinity glycopeptide for pentapeptide target not as important activity. This suggested that block access antibiotic its could be major factor determining Outer membrane proteins mutant, resistant parent, revertant strains appeared normal. The exhibited increased susceptibility both erythromycin fusidic acid which lost single-step revertants resistance. Polymyxin B nonapeptide synergistic parent but mutant. Analysis susceptibilities control E. Salmonella typhimurium known defects lipopolysaccharide (LPS) synthesis core LPS mutants (Re chemotype) phenotypically similar under study. However, migrated slightly less rapidly on sodium dodecyl sulfate-polyacrylamide gel electrophoresis than wild-type or did resemble Re chemotype obtained from rfaC rfaD mutants. These data suggest structure other loss heptose moieties may also resistance large, hydrophilic molecules glycopeptides.