Characterization of virulence gene distribution and antibiotic susceptibility profiles of diarrheagenic Escherichia coli from chicken faeces

A significant increase in the incidence of non-O157 verotoxigenic Escherichia coli (VTEC) infections have become a serious health issues, and this situation is worsening due to the dissemination of plasmid mediated multidrug-resistant microorganisms worldwide. This study aims to investigate the presence of plasmid-mediated verotoxin gene in non-O157 E. coli. Standard microbiological techniques identified a total of 137 E. coli isolates. The plasmid was detected by Perfectprep Plasmid Mini preparation kit. These isolates were subjected to disk diffusion assay, and plasmid curing with ethidium bromide treatment. The plasmid containing isolates were subjected to a polymerase chain reaction (PCR) for investigating the presence of plasmid mediated verotoxin gene (VT1 and VT2) in non-O157 E. coli. Among the 137 E. coli isolates, 49 isolates were non-O157 E. coli while 29 (59.1%) isolates were verotoxin producing non-O157 serotypes and 26 non-O157 VTEC isolates possessed plasmids. Certain isolates harboured single sized plasmid while others had multiple plasmids with different size varied from 1.8kb to 7.6kb. A plasmid containing all (100%) the isolates was multidrug-resistant. Eight isolates changed their susceptibility patterns while three isolates were found to lose plasmid after post plasmid curing treatment and the rest of the isolates (15) remained constant. Different PCR sets characterized 3 plasmid-mediated verotoxins producing non-O157 E. coli. This current study demonstrated the occurrence of plasmid mediated verotoxin gene in non-O157 E. coli. To the best of our knowledge, this is the first report in the global literature on plasmid-mediated verotoxin gene in non-O157 E. coli. Timely diagnosis and surveillance of VTEC infections should prioritize to stop or slow down the virulence gene for dissemination by plasmid-mediated gene transfer amongst the same bacteria or other species.

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Molecular Characterization of Some Virulence Genes and Antibiotic Susceptibility Pattern among Uropathogenic Escherichia coli Isolated from Patient in Zakho City/Iraq

ZANCO Journal of Pure and Applied Sciences ◽

10.21271/zjpas.32.2.18 ◽

2020 ◽

Vol 32 (2) ◽

Keyword(s):

Escherichia Coli ◽

Molecular Characterization ◽

Antibiotic Susceptibility ◽

Virulence Genes ◽

Uropathogenic Escherichia Coli ◽

Susceptibility Pattern ◽

Antibiotic Susceptibility Pattern

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Antibiotic susceptibility profiles and frequency of resistance genes in clinical Shiga toxin-producing Escherichia coli isolates from Michigan over a 14-year period

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01189-21 ◽

2021 ◽

Author(s):

Sanjana Mukherjee ◽

Heather M. Blankenship ◽

Jose A. Rodrigues ◽

Rebekah E. Mosci ◽

James T. Rudrik ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Resistance Genes ◽

Shiga Toxin ◽

Antibiotic Susceptibility ◽

Genetic Relatedness ◽

Antibiotic Resistance Genes ◽

Genomic Analysis ◽

Mechanisms Of Resistance ◽

Susceptibility Profiles

Background: Shiga toxin-producing Escherichia coli (STEC) is an important foodborne pathogen that contributes to over 250,000 infections in the US each year. Because antibiotics are not recommended for STEC infections, resistance in STEC has not been widely researched despite an increased likelihood for the transfer of resistance gene from STEC to opportunistic pathogens residing within the same microbial community. Methods: Between 2001 and 2014, 969 STEC isolates were collected from Michigan patients. Serotyping and antibiotic susceptibility profiles to clinically relevant antibiotics were determined using disc diffusion, while epidemiological data was used to identify factors associated with resistance. Whole genome sequencing was used to examine genetic relatedness and identify genetic determinants and mechanisms of resistance in the non-O157 isolates. Results: Increasing frequencies of resistance to at least one antibiotic was observed over the 14 years (p=0.01). While the non-O157 serogroups were more commonly resistant than O157 (Odds Ratio: 2.4; 95% Confidence Interval:1.43-4.05), the frequency of ampicillin resistance among O157 isolates was significantly higher in Michigan compared to the national average (p=0.03). Genomic analysis of 321 non-O157 isolates uncovered 32 distinct antibiotic resistance genes (ARGs). Although mutations in genes encoding resistance to ciprofloxacin and ampicillin were detected in four isolates, most of the horizontally acquired ARGs conferred resistance to aminoglycosides, β-lactams, sulfonamides and/or tetracycline. Conclusions: This study provides insight into the mechanisms of resistance in a large collection of clinical non-O157 STEC isolates and demonstrates that antibiotic resistance among all STEC serogroups has increased over time, prompting the need for enhanced surveillance.

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Diarrheagenic Escherichia coli pathotypes isolated from a swine farm in a region of Morelos state, Mexico

Salud Pública de México ◽

10.21149/11268 ◽

2020 ◽

Author(s):

Elsa María Tamayo-Legorreta ◽

Alejandro García-Radilla ◽

Eduardo Moreno-Vázquez ◽

Fabián Téllez-Figueroa ◽

Celia M Alpuche-Aranda

Keyword(s):

Escherichia Coli ◽

Multiplex Pcr ◽

Potential Risk ◽

Virulence Gene ◽

Central Mexico ◽

Swine Farm ◽

Fecal Samples ◽

E Coli ◽

Diarrheagenic Escherichia Coli

Objective. Determine the frequency of diarrheagenic Escherichia coli pathotypes colonizing swine. Materials and Methods. E. coli strains isolated of fecal samples from 280 swine, produced for local consumption, in a semi-technical farm of Morelos state, (central Mexico) were tested to identify the diarrheagenic E. coli pathotypes by multiplex PCR. Results. Of the 521-diarrheagenic E. coli isolates examined, 50 (9.6%) were positive for at least one virulence gene in 42 different animals. Thus, 15% (42/280) of the swine in this farm were colonized with pathogenic E. coli. Among the E. coli isolates, the pathotype EPEC (6.5%) was the most frequently, followed by EHEC (2.3%), ETEC and EIEC (0.4%). Conclusions. In this study, four different E. coli pathotypes were found among swine colonized by E. coli in this farm. Thus, these swine are reservoirs for these virulent bacteria and there is potential risk of causing diarrhea in swine and in the population consuming the meat.

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Whole Genome Sequencing Characterization of Shiga Toxin–Producing Escherichia coli Isolated from Flour from Swiss Retail Markets

Journal of Food Protection ◽

10.4315/0362-028x.jfp-18-593 ◽

2019 ◽

Vol 82 (8) ◽

pp. 1398-1404 ◽

Cited By ~ 2

Author(s):

RENATE BOSS ◽

JOERG HUMMERJOHANN

Keyword(s):

Escherichia Coli ◽

Whole Genome Sequencing ◽

Genome Sequencing ◽

Shiga Toxin ◽

Severe Disease ◽

Virulence Gene ◽

Whole Genome ◽

N 93 ◽

Human Infections

ABSTRACT Shiga toxin–producing Escherichia coli (STEC) strains are often found in food and cause human infections. Although STEC O157:H7 is most often responsible for human disease, various non-O157 subtypes have caused individual human infections or outbreaks. The importance of STEC serogroup typing is decreasing while detection of virulence gene patterns has become more relevant. Whole genome sequencing (WGS) reveals the entire spectrum of pathogen information, such as toxin variant, serotype, sequence type, and virulence factors. Flour has not been considered as a vector for STEC; however, this product has been associated with several STEC outbreaks in the last decade. Flour is a natural product, and milling does not include a germ-reducing step. Flour is rarely eaten raw, but the risks associated with the consumption of unbaked dough are probably underestimated. The aim of this study was to determine the prevalence of STEC in flour samples (n = 93) collected from Swiss markets and to fully characterize the isolates by PCR assay and WGS. The prevalence of STEC in these flour samples was 10.8% as indicated by PCR, and a total of 10 STEC strains were isolated (two flour samples were positive for two STEC subtypes). We found one stx2-positve STEC isolate belonging to the classic serogroups frequently associated with outbreaks that could potentially cause severe disease. However, we also found several other common or less common STEC subtypes with diverse virulence patterns. Our results reveal the benefits of WGS as a characterization tool and that flour is a potentially and probably underestimated source for STEC infections in humans.

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