Molecular Profiling of Shiga Toxin-Producing Escherichia coli and Enteropathogenic E. coli Strains Isolated from French Coastal Environments

ABSTRACTShiga toxin-producingEscherichia coli(STEC) and enteropathogenicE. coli(EPEC) strains may be responsible for food-borne infections in humans. Twenty-eight STEC and 75 EPEC strains previously isolated from French shellfish-harvesting areas and their watersheds and belonging to 68 distinguishable serotypes were characterized in this study. High-throughput real-time PCR was used to search for the presence of 75E. colivirulence-associated gene targets, and genes encoding Shiga toxin (stx) and intimin (eae) were subtyped using PCR tests and DNA sequencing, respectively. The results showed a high level of diversity between strains, with 17 unique virulence gene profiles for STEC and 56 for EPEC. Seven STEC and 15 EPEC strains were found to display a large number or a particular combination of genetic markers of virulence and the presence ofstxand/oreaevariants, suggesting their potential pathogenicity for humans. Among these, an O26:H11stx1aeae-β1 strain was associated with a large number of virulence-associated genes (n= 47), including genes carried on the locus of enterocyte effacement (LEE) or other pathogenicity islands, such as OI-122, OI-71, OI-43/48, OI-50, OI-57, and the high-pathogenicity island (HPI). One O91:H21 STEC strain containing 4stxvariants (stx1a,stx2a,stx2c, andstx2d) was found to possess genes associated with pathogenicity islands OI-122, OI-43/48, and OI-15. Among EPEC strains harboring a large number of virulence genes (n, 34 to 50), eight belonged to serotype O26:H11, O103:H2, O103:H25, O145:H28, O157:H7, or O153:H2.IMPORTANCEThe speciesE. coliincludes a wide variety of strains, some of which may be responsible for severe infections. This study, a molecular risk assessment study ofE. colistrains isolated from the coastal environment, was conducted to evaluate the potential risk for shellfish consumers. This report describes the characterization of virulence gene profiles andstx/eaepolymorphisms ofE. coliisolates and clearly highlights the finding that the majority of strains isolated from coastal environment are potentially weakly pathogenic, while some are likely to be more pathogenic.

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Clinical and Molecular Correlates of Escherichia coli Bloodstream Infection from Two Geographically Diverse Centers in Rochester, Minnesota, and Singapore

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00937-18 ◽

2018 ◽

Vol 62 (10) ◽

Cited By ~ 5

Author(s):

Shehara M. Mendis ◽

Shawn Vasoo ◽

Brian D. Johnston ◽

Stephen B. Porter ◽

Scott A. Cunningham ◽

...

Keyword(s):

Escherichia Coli ◽

Odds Ratio ◽

Virulence Gene ◽

Fluoroquinolone Resistance ◽

Content Type ◽

E Coli ◽

Gene Profiles ◽

Clonal Distribution ◽

To Receive ◽

Community Onset

ABSTRACT Escherichia coli bacteremia is caused mainly by sequence type complex 131 (STc131) and two clades within its fluoroquinolone-resistance-associated H30 subclone, H30R1 and H30Rx. We examined clinical and molecular correlates of E. coli bacteremia in two geographically distinct centers. We retrospectively studied 251 unique E. coli bloodstream isolates from 246 patients (48 from the Mayo Clinic, Rochester, MN [MN], and 198 from Tan Tock Seng Hospital, Singapore [SG]), from October 2013 through March 2014. Isolates underwent PCR for phylogroup, STc, blaCTX-M type, and virulence gene profiles, and medical records were reviewed. Although STc131 accounted for 25 to 27% of all E. coli bacteremia isolates at each site, its extended-spectrum-β-lactamase (ESBL)-associated H30Rx clade was more prominent in SG than in MN (15% versus 4%; P = 0.04). In SG only, patients with STc131 (versus other E. coli STc isolates) were more likely to receive inactive initial antibiotics (odds ratio, 2.8; P = 0.005); this was true specifically for patients with H30Rx (odds ratio, 7.0; P = 0.005). H30Rx comprised 16% of community-onset bacteremia episodes in SG but none in MN. In SG, virulence scores were higher for H30Rx than for H30R1, non-H30 STc131, and non-STc131 isolates (P < 0.02 for all comparisons). At neither site did mortality differ by clonal status. The ESBL-associated H30Rx clade was more prevalent and more often of community onset in SG, where it predicted inactive empirical treatment. The clonal distribution varies geographically and has potentially important clinical implications. Rapid susceptibility testing and clonal diagnostics for H30/H30Rx might facilitate earlier prescribing of active therapy.

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Emergence of a Multidrug-Resistant Shiga Toxin-Producing Enterotoxigenic Escherichia coli Lineage in Diseased Swine in Japan

Journal of Clinical Microbiology ◽

10.1128/jcm.03141-15 ◽

2016 ◽

Vol 54 (4) ◽

pp. 1074-1081 ◽

Cited By ~ 23

Author(s):

Masahiro Kusumoto ◽

Yuna Hikoda ◽

Yuki Fujii ◽

Misato Murata ◽

Hirotsugu Miyoshi ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Significant Risk ◽

Multidrug Resistant ◽

Limited Range ◽

Enterotoxigenic Escherichia Coli ◽

Content Type ◽

E Coli ◽

Shigella Boydii ◽

High Level

EnterotoxigenicEscherichia coli(ETEC) and Shiga toxin-producingE. coli(STEC) are important causes of diarrhea and edema disease in swine. The majority of swine-pathogenicE. colistrains belong to a limited range of O serogroups, including O8, O138, O139, O141, O147, O149, and O157, which are the most frequently reported strains worldwide. However, the circumstances of ETEC and STEC infections in Japan remain unknown; there have been few reports on the prevalence or characterization of swine-pathogenicE. coli. In the present study, we determined the O serogroups of 967E. coliisolates collected between 1991 and 2014 from diseased swine in Japan, and we found that O139, O149, O116, and OSB9 (O serogroup ofShigella boydiitype 9) were the predominant serogroups. We further analyzed these four O serogroups using pulsed-field gel electrophoresis (PFGE), multilocus sequence typing, and virulence factor profiling. Most of the O139 and O149 strains formed serogroup-specific PFGE clusters (clusters I and II, respectively), whereas the O116 and OSB9 strains were grouped together in the same cluster (cluster III). All of the cluster III strains belonged to a single sequence type (ST88) and carried genes encoding both enterotoxin and Shiga toxin. This PFGE cluster III/ST88 lineage exhibited a high level of multidrug resistance (to a median of 10 antimicrobials). Notably, these bacteria were resistant to fluoroquinolones. Thus, this lineage should be considered a significant risk to animal production due to the toxigenicity and antimicrobial resistance of these bacteria.

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Diverse Virulence Gene Content of Shiga Toxin-Producing Escherichia coli from Finishing Swine

Applied and Environmental Microbiology ◽

10.1128/aem.01761-14 ◽

2014 ◽

Vol 80 (20) ◽

pp. 6395-6402 ◽

Cited By ~ 25

Author(s):

Marion Tseng ◽

Pina M. Fratamico ◽

Lori Bagi ◽

Sabine Delannoy ◽

Patrick Fach ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Virulence Genes ◽

Genetic Relatedness ◽

Virulence Gene ◽

Health Concern ◽

Limited Information ◽

Content Type ◽

Genes Encoding ◽

Critical Public Health

ABSTRACTShiga toxin-producingEscherichia coli(STEC) infections are a critical public health concern because they can cause severe clinical outcomes, such as hemolytic uremic syndrome, in humans. Determining the presence or absence of virulence genes is essential in assessing the potential pathogenicity of STEC strains. Currently, there is limited information about the virulence genes carried by swine STEC strains; therefore, this study was conducted to examine the presence and absence of 69 virulence genes in STEC strains recovered previously from finishing swine in a longitudinal study. A subset of STEC strains was analyzed by pulsed-field gel electrophoresis (PFGE) to examine their genetic relatedness. Swine STEC strains (n= 150) were analyzed by the use of a high-throughput real-time PCR array system, which included 69 virulence gene targets. Three major pathotypes consisted of 16 different combinations of virulence gene profiles, and serotypes were determined in the swine STEC strains. The majority of the swine STEC strains (n= 120) belonged to serotype O59:H21 and carried the same virulence gene profile, which consisted of 9 virulence genes:stx2e,iha,ecs1763,lpfAO113,estIa(STa),ehaA,paa,terE, andureD. Theeae,nleF, andnleH1-2genes were detected in one swine STEC strain (O49:H21). Other genes encoding adhesins, includingiha, were identified (n= 149). The PFGE results demonstrated that swine STEC strains from pigs raised in the same finishing barn were closely related. Our results revealed diverse virulence gene contents among the members of the swine STEC population and enhance understanding of the dynamics of transmission of STEC strains among pigs housed in the same barn.

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An Environmental Shiga Toxin-Producing Escherichia coli O145 Clonal Population Exhibits High-Level Phenotypic Variation That Includes Virulence Traits

Applied and Environmental Microbiology ◽

10.1128/aem.03172-15 ◽

2015 ◽

Vol 82 (4) ◽

pp. 1090-1101 ◽

Cited By ~ 17

Author(s):

Michelle Qiu Carter ◽

Beatriz Quinones ◽

Xiaohua He ◽

Wayne Zhong ◽

Jacqueline W. Louie ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Virulence Determinants ◽

Content Type ◽

Clinical Strains ◽

Production Region ◽

E Coli ◽

Virulence Traits ◽

Virulence Potential ◽

High Level

ABSTRACTShiga toxin-producingEscherichia coli(STEC) serotype O145 is one of the major non-O157 serotypes associated with severe human disease. Here we examined the genetic diversity, population structure, virulence potential, and antimicrobial resistance profiles of environmental O145 strains recovered from a major produce production region in California. Multilocus sequence typing analyses revealed that sequence type 78 (ST-78), a common ST in clinical strains, was the predominant genotype among the environmental strains. Similarly, all California environmental strains belonged to H28, a common H serotype in clinical strains. Although most environmental strains carried an intactfliCgene, only one strain retained swimming motility. Diversestxsubtypes were identified, includingstx1a,stx2a,stx2c, andstx2e. Although no correlation was detected between thestxgenotype and Stx1 production, high Stx2 production was detected mainly in strains carryingstx2aonly and was correlated positively with the cytotoxicity of Shiga toxin. All environmental strains were capable of producing enterohemolysin, whereas only 10 strains were positive for anaerobic hemolytic activity. Multidrug resistance appeared to be common, as nearly half of the tested O145 strains displayed resistance to at least two different classes of antibiotics. The core virulence determinants of enterohemorrhagicE. coliwere conserved in the environmental STEC O145 strains; however, there was large variation in the expression of virulence traits among the strains that were highly related genotypically, implying a trend of clonal divergence. Several cattle isolates exhibited key virulence traits comparable to those of the STEC O145 outbreak strains, emphasizing the emergence of hypervirulent strains in agricultural environments.

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Shiga Toxin-Producing Escherichia coli (STEC) and STEC-Associated Virulence Genes in Raw Ground Pork in Canada

Journal of Food Protection ◽

10.4315/jfp-21-147 ◽

2021 ◽

Author(s):

Helen Zhang ◽

Etsuko Yamamoto ◽

Johanna Murphy ◽

Catherine Carrillo ◽

Annie Locas

Keyword(s):

Escherichia Coli ◽

Foodborne Pathogens ◽

Shiga Toxin ◽

Virulence Genes ◽

Virulence Gene ◽

Toxin Gene ◽

Gene Profiles ◽

Ground Pork ◽

Genes Encoding ◽

Human Illness

Shiga toxin-producing Escherichia coli (STEC) O157:H7/NM and some non-O157 STEC are foodborne pathogens. In response to pork-associated O157 STEC outbreaks in Canada, we investigated the occurrence of STEC in Canadian retail raw ground pork during the period of November 1, 2014 and March 31, 2016. Isolated STEC were characterized to determine the Shiga-toxin gene ( stx ) subtype and the presence of virulence genes encoding intimin ( eae ), and enterohemorrhagic E. coli hemolysin (hlyA) . O157 STEC and non-O157 STEC were isolated from 0.11% (1/879) and 2.24% (13/580) of the pork samples. STEC virulence gene profiles containing both eae and hlyA were found only in the O157 STEC ( stx 2a , eae , hlyA ) isolate. The eae gene was absent from all non-O157 STEC isolates. Of the 13 non-O157 STEC isolates, two virulence genes of stx 1a and hlyA were found in four (30.8%) O91:H14 STEC isolates, while one virulence gene of stx 2e, stx 1a , and stx 2a was identified in five (38.5%), two (15.4%) and one (7.7%) STEC isolates respectively of various serotypes. The remaining non-O157 STEC isolate carried stx 2 , but the subtype is unknown as this isolate could not be recovered for sequencing. O91:H14 STEC ( stx 1a, hlyA ) was previously reported in association with diarrhea illnesses, while the other non-O157 STEC isolates identified in this study are not known to be associated with severe human illnesses. Virulence gene profiles identified in this study indicate that the occurrence of non-O157 STEC capable of causing severe human illness is rare in Canadian retail pork. However, O157 STEC in ground pork can occasionally occur, therefore education regarding the potential risks associated with STEC contamination of pork would be beneficial for the public and those in the food industry in order to help reduce foodborne illnesses.

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Complete Genome Sequence of Escherichia coli Phage vB_EcoS Sa179lw, Isolated from Surface Water in a Produce-Growing Area in Northern California

Genome Announcements ◽

10.1128/genomea.00337-18 ◽

2018 ◽

Vol 6 (27) ◽

Cited By ~ 2

Author(s):

Yen-Te Liao ◽

Fang Liu ◽

Xincheng Sun ◽

Robert W. Li ◽

Vivian C. H. Wu

Keyword(s):

Escherichia Coli ◽

Surface Water ◽

Genome Sequence ◽

Shiga Toxin ◽

Virulence Gene ◽

Whole Genome Sequence ◽

Whole Genome ◽

Content Type ◽

E Coli ◽

Escherichia Coli Phage

We report here the whole-genome sequence of a novel Escherichia coli phage, vB_EcoS Sa179lw, isolated from surface water collected in a produce-growing area. With the presence of a putative eae-like gene that was associated with previous non-O157 Shiga toxin-producing E. coli outbreaks, this phage is a candidate for the study of virulence gene transfer.

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Relationship between Virulence Gene Profiles of Atypical Enteropathogenic Escherichia coli and Shiga Toxin- Producing E. coli Isolates from Cattle and Sheep in New Zealand

Applied and Environmental Microbiology ◽

10.1128/aem.02528-09 ◽

2010 ◽

Vol 76 (11) ◽

pp. 3744-3747 ◽

Cited By ~ 9

Author(s):

Adrian L. Cookson ◽

Mingshu Cao ◽

Jenny Bennett ◽

Carolyn Nicol ◽

Fiona Thomson-Carter ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Evolutionary Relationship ◽

Virulence Gene ◽

Type Ii Secretion ◽

E Coli ◽

Type Ii Secretion System ◽

Gene Profiles ◽

The Relationship ◽

Cattle And Sheep

ABSTRACT Virulence gene profiles of atypical enteropathogenic Escherichia coli (aEPEC) and Shiga toxin-producing E. coli (STEC) from cattle, sheep, and humans were examined to determine the relationship between pathotypes. Shared virulence factors (intimin, EHEC hemolysin, serine protease, and a type II secretion system) were identified, suggesting a dynamic evolutionary relationship between aEPEC and STEC.

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Geographically Distinct Escherichia coli O157 Isolates Differ by Lineage, Shiga Toxin Genotype, and Total Shiga Toxin Production

Journal of Clinical Microbiology ◽

10.1128/jcm.01532-14 ◽

2014 ◽

Vol 53 (2) ◽

pp. 579-586 ◽

Cited By ~ 26

Author(s):

Glen E. Mellor ◽

Narelle Fegan ◽

Kari S. Gobius ◽

Helen V. Smith ◽

Amy V. Jennison ◽

...

Keyword(s):

United States ◽

Escherichia Coli ◽

Shiga Toxin ◽

Toxin Production ◽

The United States ◽

Content Type ◽

E Coli ◽

Gene Profiles ◽

Disease Rates ◽

Regional Disease

While the differential association ofEscherichia coliO157 genotypes with animal and human hosts has recently been well documented, little is known about their distribution between countries and how this might affect regional disease rates. Here, we used a 48-plex single nucleotide polymorphism (SNP) assay to segregate 148E. coliO157 isolates from Australia, Argentina, and the United States into 11 SNP lineages. We also investigated the relationship between SNP lineages, Shiga toxin (Stx) gene profiles, and total Stx production.E. coliO157 isolates clearly segregated into SNP lineages that were differentially associated with each country. Of the 11 SNP lineages, seven were detected among isolates from a single country, two were detected among isolates from all three countries, and another two were detected only among U.S. and Argentinean isolates. A number of Australian (30%) and Argentinean (14%) isolates were associated with novel, previously undescribed SNP lineages that were unique to each country. Isolates within SNP lineages that were strongly associated with the carriage ofstx2aproduced comparatively more Stx on average than did those lacking thestx2asubtype. Furthermore, the proportion of isolates instx2a-associated SNP lineages was significantly higher in Argentina and the United States than Australia (P< 0.05). This study provides evidence for the geographic divergence ofE. coliO157 and for a prominent role ofstx2ain total Stx production. These results also highlight the need for more comprehensive studies of the global distribution ofE. coliO157 lineages and the impacts of regionally predominantE. coliO157 lineages on the prevalence and severity of disease.

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Adherent-Invasive Escherichia coli Phenotype Displayed by Intestinal Pathogenic E. coli Strains from Cats, Dogs, and Swine

Applied and Environmental Microbiology ◽

10.1128/aem.02614-10 ◽

2011 ◽

Vol 77 (16) ◽

pp. 5813-5817 ◽

Cited By ~ 16

Author(s):

Margarita Martinez-Medina ◽

Jesus Garcia-Gil ◽

Nicolas Barnich ◽

Lothar H. Wieler ◽

Christa Ewers

Keyword(s):

Escherichia Coli ◽

Crohn’S Disease ◽

Crohn's Disease ◽

Virulence Gene ◽

Content Type ◽

E Coli ◽

Gene Profiles ◽

Putative Role ◽

Phylogenetic Origin ◽

Disease Specificity

ABSTRACTThe adherent-invasiveEscherichia coli(AIEC) pathotype, which has been associated with Crohn's disease, shows similar traits to human and animal extraintestinal pathogenicE. coli(ExPEC) with respect to their phylogenetic origin and virulence gene profiles. Here, we demonstrate that animal ExPEC strains generally do not share the AIEC phenotype. In contrast, this phenotype is very frequent among animal intestinal pathogenicE. coli(InPEC) strains, particularly of feline and canine origin, that genetically resemble ExPEC. These results strengthen the particular identity and disease specificity of the AIEC pathotype and the putative role animals might play in the transmission of AIEC-like strains to humans.

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Phylogenetic and Molecular Analysis of Food-Borne Shiga Toxin-Producing Escherichia coli

Applied and Environmental Microbiology ◽

10.1128/aem.03552-12 ◽

2013 ◽

Vol 79 (8) ◽

pp. 2731-2740 ◽

Cited By ~ 27

Author(s):

Elisabeth Hauser ◽

Alexander Mellmann ◽

Torsten Semmler ◽

Helen Stoeber ◽

Lothar H. Wieler ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Virulence Gene ◽

Human Infection ◽

Pathogenic Potential ◽

Content Type ◽

E Coli ◽

Food Borne ◽

Strain Collection ◽

Integration Sites

ABSTRACTSeventy-five food-associated Shiga toxin-producingEscherichia coli(STEC) strains were analyzed by molecular and phylogenetic methods to describe their pathogenic potential. The presence of the locus of proteolysis activity (LPA), the chromosomal pathogenicity island (PAI) PAI ICL3, and the autotransporter-encoding genesabAwas examined by PCR. Furthermore, the occupation of the chromosomal integration sites of the locus of enterocyte effacement (LEE),selC,pheU, andpheV, as well as the Stx phage integration sitesyehV,yecE,wrbA,z2577, andssrA, was analyzed. Moreover, the antibiotic resistance phenotypes of all STEC strains were determined. Multilocus sequence typing (MLST) was performed, and sequence types (STs) and sequence type complexes (STCs) were compared with those of 42 hemolytic-uremic syndrome (HUS)-associated enterohemorrhagicE. coli(HUSEC) strains. Besides 59 STs and 4 STCs, three larger clusters were defined in this strain collection. Clusters A and C consist mostly of highly pathogeniceae-positive HUSEC strains and some related food-borne STEC strains. A member of a new O26 HUS-associated clone and the 2011 outbreak strainE. coliO104:H4 were found in cluster A. Cluster B comprises onlyeae-negative food-borne STEC strains as well as mainlyeae-negative HUSEC strains. Although food-borne strains of cluster B were not clearly associated with disease, serotypes of important pathogens, such as O91:H21 and O113:H21, were in this cluster and closely related to the food-borne strains. Clonal analysis demonstrated eight closely related genetic groups of food-borne STEC and HUSEC strains that shared the same ST and were similar in their virulence gene composition. These groups should be considered with respect to their potential for human infection.

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