PMID:1656859

From OMPwiki
Jump to: navigation, search
Citation

Hancock, RE, Farmer, SW, Li, ZS and Poole, K (1991) Interaction of aminoglycosides with the outer membranes and purified lipopolysaccharide and OmpF porin of Escherichia coli.Antimicrob. Agents Chemother. 35:1309-14

Abstract

The mechanism of uptake of aminoglycosides across the outer membrane of Escherichia coli was reevaluated. Porin-deficient mutants showed no alteration in gentamicin or kanamycin susceptibility. Furthermore, the influence of kanamycin on intrinsic tryptophan fluorescence of porin OmpF (Y. Kobayashi, and T. Nakae, Eur. J. Biochem. 151:231-236, 1985) was shown to be strongly influenced by protein concentration and EDTA. This led to the hypothesis that aminoglycoside-mediated increases and decreases in intrinsic tryptophan fluorescence were due to aggregation-disaggregation of OmpF mediated by interaction at a divalent cation binding site on OmpF. Gentamicin, kanamycin, and polymyxin B increased E. coli outer membrane permeability to the hydrophobic fluorescent compound 1-N-phenyl-naphthylamine (NPN) and the peptidoglycan-degrading enzyme lysozyme. Addition of Mg2+ blocked these permeabilizing activities. Furthermore, gentamicin and polymyxin B bound to Mg(2+)-binding sites on E. coli lipopolysaccharide, as determined in dansyl polymyxin displacement experiments. A polymyxin-resistant, lipopolysaccharide-altered pmr mutant of E. coli had a fourfold-lower MIC of gentamicin and kanamycin and was more poorly permeabilized to 1-N-phenylnaphthylamine than was its parent strain. These data were consistent with uptake of aminoglycosides across the E. coli outer membrane by the self-promoted uptake mechanism.

Links

PubMed

Keywords

Anti-Bacterial Agents; Bacterial Outer Membrane Proteins; Culture Media; Escherichia coli; Gentamicins; Kanamycin; Lipopolysaccharides; Polymyxin B; Porins

Main Points of the Paper

Please summarize the main points of the paper.

Materials and Methods Used

Please list the materials and methods used in this paper (strains, plasmids, antibodies, etc).

Phenotype Annotations

See Help:AnnotationTable for details on how to edit this table.

Phenotype of Taxon Information Genotype Information (if known) Condition Information OMP ID OMP Term Name ECO ID ECO Term Name Notes Status

a mutation or genetic difference within a strain

  • Taxon: Escherichia coli
  • Strain: K-12
  • Substrain: SC9252
  • NCBI Taxon ID: 83333
  • Genotype of Reference Strain: pmrA
  • Genotype of Experimental Strain : pmrA
  • Reference Condition:
OMP:0000276

increased resistance to antimicrobial compound

ECO:0000182

in vitro culture assay data

Resistant to polymyxin, table 1

a mutation or genetic difference within a strain

  • Taxon: Escherichia coli
  • Strain: K-12
  • Substrain: SC9252
  • NCBI Taxon ID: 83333
  • Genotype of Reference Strain: pmrA
  • Genotype of Experimental Strain : pmrA
  • Reference Condition:
OMP:0000276

increased resistance to antimicrobial compound

ECO:0000182

in vitro culture assay data

Resistant to Gentamicin, table 1


Notes

References

See Help:References for how to manage references in OMPwiki.