Non Lactose Fermenting Escherichia Coli and Shiga Toxin

Abstract

Non-lactose-fermenting Escherichia coli (NLFEC) has a few descriptive studies restricted to infections in humans. Isolates of NLFEC characterised by their virulence ability, biofilm formation capacity and antimicrobial susceptibility profile. E.coli lactose-fermenting strains with the same conditions were analysed to provide comparisons. The non-lactose-fermenting E. coli strains were classifiedes belonging to clade I E. coli, whereas the lactose-fermenting strains were classified in phylo group B2. The virulence markers were present in all strains. adhesion, iron accumulation, toxins, colicin and cytotoxin production biofilm regulation. In addition to the extracellular matrix components, the ability of the strains to form in vitro biofilms has been demonstrated. Multidrug resistance (MDR) profiles were observed by in vitro susceptibility tests to all NLFEC strains. Non-lactose-fermenting E. coli behaves similar to lactose-fermenting E. coli, exhibiting MDR. The lactose non-fermenters underwent PCR-based O typing, multilocus sequence.typing (MLST) analysis, phylogenetic grouping. Resistance mechanisms have been studied for ciprofloxacin resistant isolates. From (19.7%) isolates were lactose non-fermenters and the ciprofloxacin resistance rate was significantly higher than in lactose fermenters. We have investigated the prevalence and characteristics of lactose intolerance in isolates from E. coli in this study.