conclusions our study emphasized the increasing role of esbl genes, especially blactx-m15 in epec isolates. results of 42 epec, eight isolates carried the blactx-m1. none of the isolates carried blactx-m2 and blactx-m9. the blactx-m15 variant was identified in all of blactx-m1-positive isolates. furthermore, blashv and blatem genes were detected in 40.5% (n = 17) and 19% (n = 8) of all epec iso...

conclusions the activities studied by the production of pnp were determined by following the increase at 410 nm. the maximum pnp was produced at 30°c with an optical density of 10.62 in the presence of cytoplasmic expression of oph (pet21a-opd). consequently, our results suggest cytoplasmic expression system as an appropriate candidate with a high amount of oph in spite of inclusion body format...

conclusions this study indicated the contamination of lettuce by stec strains and its possible role as the source of infection. resistance to both tetracycline and ampicillin may be considered as an emergency alarm for a multidrug resistance of stec strains. results eight samples were positive for presence of stec strains, three contained stx1, five contained stx2, and one sample was positive f...

results in this study, high resistances were found to nalidixic acid (59.7%) and gentamicin (52.3%) but high susceptibilities were found to ciprofloxacin (59.3%) and ceftriaxone (36.3%). conclusions according to the results obtained in this study ciprofloxacin is an effective antibiotic in e. coli infections. objectives the current study aimed to investigate the resistance of escherichia coli a...

background infectious diarrhoeal diseases cause major problems throughout the world and are responsible for considerable morbidity and mortality. enteropathogenic escherichia coli (epec) may cause infantile diarrhoea among children in developing countries. objectives the aim of this study was to define the prevalence of epec strains in raw milk samples. materials and methods raw milk samples co...

L-2-methyltryptophan was prepared from L-serine and 2-methylindole catalyzed by recombinant Escherichia coli with tryptophan synthase activity. In the present research, we used tryptophan synthase (TSase) from recombinant Escherichia coli with pET28a-trpBA plasmid expressing tryptophan synthase from Escherichia coli k-12 MG1655 to produce 2-methyltryptophan, and optimized the conditions for enz...

Escherichia coli possesses a number of specific K(+) influx and efflux systems that maintain an appropriate intracellular K(+) concentration. Although regulatory mechanisms have been identified for a number of these transport systems, the exact mechanism through which K(+) concentration is sensed in the cell remains unknown. In this work we show that Kbp (K(+) binding protein, formerly YgaU), a...

We analyzed the prevalence of diarrheagenic Escherichia coli (DEC) markers and common phenotypes in 2,164 E. coli isolates from 282 DEC-positive samples. Enteropathogenic E. coli (EPEC) and enteroaggregative E. coli (EAEC) were very diverse and were not correlated with diarrhea. Enterotoxigenic E. coli (ETEC) estA and enterohemorrhagic E. coli (EHEC) belonged to a few phenotypes and were signif...