Modification of outer membrane permeability and alteration of LPS in veterinary enterotoxigenic Escherichia coli - Aix-Marseille Université Access content directly
Journal Articles Research in Veterinary Science Year : 2019

Modification of outer membrane permeability and alteration of LPS in veterinary enterotoxigenic Escherichia coli

Abstract

Enterotoxigenic Escherichia coli (ETEC) is a worrying cause of diarrhoea in calves and the drug multiresistance phenotype concerning various antibiotic families are of concern. Resistance mechanisms associated with envelope changes (porin expression, efflux pump overexpression, lipolysaccahride (LPS) modification) were studied in 14 ETEC isolates selected for their resistance. We performed determinations of (i) antimicrobials Minimal Inhibitory Concentrations with or without the efflux pump inhibitor phenylalanine arginine β-naphthylamide; (ii) colistin and polymyxin MICs with and without EDTA, (iii) intracellular accumulation of chloramphenicol in presence of an energy uncoupler of pump energy, (iv) and immunodetection of porins and evaluation of porin trimers thermostability. Results indicated that 9 strains presented significant efflux mechanisms overexpression, among them 8 were resistant to colistin and polymyxin B due to a modification of LPS structure as evidenced by EDTA effect and silver staining electrophoresis. The high resistant strains to colistin and polymyxin exhibited identical LPS patterns. Studies of E. coli porins indicated that the majority of strains didn't show modification in their amount, however analysis of porin thermostability showed that porin trimers of some resistant strains were relatively heat-labile, suggesting a misassembly of the functional trimer. The multidrug resistance (MDR) phenotypes detected in these selected ETEC corresponded to association of LPS modifications, abordive assembly of porin trimers and active efflux which drastically alter the antibiotic activity currently used to combat enteric infections caused by this pathogen.
Fichier principal
Vignette du fichier
MODIFICATION OF OUTER MEMBRANE PERMEABILITY AND ALTERATION OF LPS IN VETERINARY ENTEROTOXIGENIC ESCHERICHIA COLI..pdf (400.72 Ko) Télécharger le fichier
Origin : Files produced by the author(s)
Loading...

Dates and versions

hal-02649532 , version 1 (02-06-2020)

Identifiers

Cite

Anne Davin-Regli, Véronique Guérin-Faublée, Jean-Marie Pagès. Modification of outer membrane permeability and alteration of LPS in veterinary enterotoxigenic Escherichia coli. Research in Veterinary Science, 2019, 124, pp.321-327. ⟨10.1016/j.rvsc.2019.04.011⟩. ⟨hal-02649532⟩
33 View
140 Download

Altmetric

Share

Gmail Facebook X LinkedIn More