Novel Hybrid of Typical Enteropathogenic Escherichia coli and Shiga-Toxin-Producing E. coli (tEPEC/STEC) Emerging From Pet Birds

Even if serotyping based on O antigens is still routinely used by most laboratories for the detection of diarrheagenic Escherichia coli, this method can provide false-positive reactions, due to the high diversity of O antigens. Molecular methods represent a valuable tool that clarifies these situations. In the Bacteriology Laboratory of Mureș County Hospital, between May 2016 and July 2019, 160 diarrheagenic E. coli strains were isolated from children under 2 years old with diarrheic disease. The strains were identified as Shiga toxin-producing E. coli (STEC)/enteropathogenic Escherichia coli (EPEC) via agglutination with polyvalent sera. STEC strains were serotyped using monovalent sera for serogroup O157. Simplex PCR was performed on the strains to determine the presence of the hlyA gene, and, for the positive ones, the hemolytic activity was tested. Antibiotic susceptibility of the identified diarrheagenic E. coli strains was also investigated. STEC strains were the most frequently identified (49.1%), followed by EPEC (40.2%). The hlyA gene was identified in 12 cases, representing 18.2% of the STEC strains. Even if the extended-spectrum β-lactamase (ESBL)-producing strains represented only 10%, a relevant percentage of multidrug-resistant (MDR) strains (24%) was identified.

Download Full-text

Prevalence of Shiga Toxin-Producing and Enteropathogenic Escherichia coli in Wild and Pet Birds in Iran

Brazilian Journal of Poultry Science ◽

10.1590/1516-635x1704445-450 ◽

2015 ◽

Vol 17 (4) ◽

pp. 445-450 ◽

Cited By ~ 8

Author(s):

A Koochakzadeh ◽

M Askari Badouei ◽

T Zahraei Salehi ◽

S Aghasharif ◽

M Soltani ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Enteropathogenic Escherichia Coli ◽

Pet Birds

Download Full-text

Outbreak of multiple strains of non-O157 Shiga toxin-producing and enteropathogenic Escherichia coli associated with rocket salad, Finland, autumn 2016

Eurosurveillance ◽

10.2807/1560-7917.es.2018.23.35.1700666 ◽

2018 ◽

Vol 23 (35) ◽

Cited By ~ 11

Author(s):

Sohvi Kinnula ◽

Kaisa Hemminki ◽

Hannele Kotilainen ◽

Eeva Ruotsalainen ◽

Eveliina Tarkka ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Food Samples ◽

Control Measures ◽

National Surveillance ◽

Enteropathogenic Escherichia Coli ◽

E Coli ◽

Clinical Laboratories ◽

Helsinki Metropolitan Area ◽

Multiple Strains

In August 2016, an outbreak of Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) with 237 cases occurred in the Helsinki metropolitan area, Finland. Gastroenteritis cases were reported at 11 events served by one catering company. Microbiological and epidemiological investigations suggested rocket salad as the cause of the outbreak. STEC ONT:H11 and EPEC O111:H8 strains isolated from food samples containing rocket were identical to the patient isolates. In this outbreak, the reported symptoms were milder than considered before for STEC infection, and the guidelines for STEC control measures need to be updated based on the severity of the illness. Based on our experience in this outbreak, national surveillance criteria for STEC have been updated to meet the practice in reporting laboratories covering both PCR-positive and culture-confirmed findings. We suggest that EPEC could be added to the national surveillance since diagnostics for EPEC are routinely done in clinical laboratories.

Download Full-text

Spheroplasts of enteropathogenic Escherichia coli. I. Biological characteristics

Canadian Journal of Microbiology ◽

10.1139/m68-112 ◽

1968 ◽

Vol 14 (6) ◽

pp. 675-678 ◽

Cited By ~ 3

Author(s):

B. Diena ◽

R. Wallace ◽

L. Greenberg

Keyword(s):

Escherichia Coli ◽

Tissue Culture ◽

Biological Characteristics ◽

Enteropathogenic Escherichia Coli ◽

E Coli ◽

O Antigen ◽

Pathogenic Serotypes

The properties of glycine-induced spheroplasts of six pathogenic serotypes of E. coli were investigated. Fimbriae and flagella appeared to be only partially synthesized as was the somatic O antigen. Cytopathogenicity of these spheroplasts for tissue culture was reduced and the infection of the monolayers was retarded as compared with the normal bacillary forms. Sensitivity to phage was almost completely lost, suggesting that glycine had either interfered with the synthesis of phage receptors or had altered the mucopeptide layerwhich is the substrate for phage enzymes. Alternatively, the phage may become a prophage inside the spheroplast with the loss of virulence.

Download Full-text

Comparison of colony and stool blots for detection of enteropathogens by DNA probes

Canadian Journal of Microbiology ◽

10.1139/m91-066 ◽

1991 ◽

Vol 37 (5) ◽

pp. 407-410

Author(s):

Mônica A. M. Vieira ◽

Beatriz E. C. Guth ◽

Tânia A. T. Gomes

Keyword(s):

Escherichia Coli ◽

Key Words ◽

Sensitivity And Specificity ◽

Dna Probes ◽

Type I ◽

Enteropathogenic Escherichia Coli ◽

Key Words Dna ◽

E Coli ◽

Heat Stable

DNA probes that identify genes coding for heat-labile type I (LT-I) and heat-stable type 1 (ST-I) enterotoxins, enteropathogenic Escherichia coli adherence factor (EAF), and Shigella-like, invasiveness (INV) are used to evaluate the sensitivity and specificity of stool blots in comparison with the sensitivity and specificity of colony blots in detecting enteropathoghens. The sensitivities of the probes in stool blots are 91.7% for the LT-I probe, 76.9% for the ST-I probes, 78.9% for the EAF probe, and 45.5% for the INV probe. The specificity of all probes is higher than 95%. In general, the stool blot method identifies as many if not more LT-I-, ST-I-, and EAF-producing E. coli infections than the colony blots. Key words: DNA probes, stool blots, enteropathogens, diagnosis.

Download Full-text

Prevalence and molecular characterisation of shiga-toxin-producing Escherichia coli in raw milk cheeses from Lazio region, Italy

Italian Journal of Food Safety ◽

10.4081/ijfs.2016.4566 ◽

2016 ◽

Vol 5 (1) ◽

Cited By ~ 3

Author(s):

Selene Marozzi ◽

Paola De Santis ◽

Sarah Lovari ◽

Roberto Condoleo ◽

Stefano Bilei ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Raw Milk ◽

Foodborne Diseases ◽

Control Plan ◽

Lazio Region ◽

Standard Methods ◽

E Coli ◽

Regional Control ◽

Unpasteurized Milk

In recent years, the incidence of foodborne diseases caused by shiga toxin-producing Escherichia coli (STEC) has increased globally. For this reason, within the specific regional control plan for the detection of STEC in food products in Italy, the presence of STEC in unpasteurized milk cheeses was investigated. In total 203 samples obtained from March 2011 to December 2013 were analysed, with two standard methods (ISO 16654:2001 and ISO 13136:2012). Two strains of E. coli O157 were isolated (2/161, 1.2%) but did not carry any virulence-associated genes and 22 stx-positive samples (22/146, 15.1%) were detected in enrichment cultures, mostly from ovine cheeses. Only two strains isolated from different ovine cheeses carried stx gene and none of these was eae-positive. This study confirms the presence of stx-positive E. coli and suggests that this type of food cannot be excluded as a potential vehicle of STEC.

Download Full-text

Enterohemorrhagic Escherichia coli Colony Check Assay for the Identification of Serogroups O26, O45, O103, O111, O121, O145, and O157 Colonies Isolated on Plating Media

Journal of Food Protection ◽

10.4315/0362-028x.jfp-13-555 ◽

2014 ◽

Vol 77 (7) ◽

pp. 1212-1218 ◽

Cited By ~ 1

Author(s):

BURTON BLAIS ◽

MYLÈNE DESCHÊNES ◽

GEORGE HUSZCZYNSKI ◽

MARTINE GAUTHIER

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

High Throughput Screening ◽

Enterohemorrhagic Escherichia Coli ◽

Test Results ◽

Bacterial Strains ◽

Enrichment Broth ◽

Substrate Solution ◽

E Coli ◽

Assay Performance

A simple immunoenzymatic enterohemorrhagic Escherichia coli (EHEC) colony check (ECC) assay was developed for the presumptive identification of priority EHEC colonies isolated on plating media from enrichment broth cultures of foods. With this approach, lipopolysaccharide extracted from a colony is spotted on the grid of a polymyxin-coated polyester cloth strip, and bound E. coli serogroup O26, O45, O103, O111, O121, O145, and O157 antigens are subsequently detected by sequential reactions with a pool of commercially available peroxidase-conjugated goat antibodies and tetramethylbenzidine substrate solution. Each strip can accommodate up to 15 colonies, and test results are available within 30 min. Assay performance was verified using colonies from a total of 73 target EHEC isolates covering the range of designated priority serogroups (all of which were reactive), 41 nontarget E. coli isolates including several nontarget Shiga toxin–producing E. coli serogroups (all unreactive), and 33 non–E. coli strains (all unreactive except two bacterial strains possessing O-antigenic structures in common with those of the priority EHEC). The ECC assay was reactive with target colonies grown on several types of selective and nonselective plating media designed for their cultivation. These results support the use of the ECC assay for high-throughput screening of colonies isolated on plating media for detecting priority EHEC strains in foods.

Download Full-text

Transcriptomic Analysis of Shiga Toxin-Producing Escherichia coli during Initial Contact with Cattle Colonic Explants

Microorganisms ◽

10.3390/microorganisms8111662 ◽

2020 ◽

Vol 8 (11) ◽

pp. 1662

Author(s):

Zachary R. Stromberg ◽

Rick E. Masonbrink ◽

Melha Mellata

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Bacterial Colonization ◽

Coli Strain ◽

Fold Change ◽

Initial Contact ◽

Lon Protease ◽

E Coli ◽

Log2 Fold Change ◽

Colonization Factors

Foodborne pathogens are a public health threat globally. Shiga toxin-producing Escherichia coli (STEC), particularly O26, O111, and O157 STEC, are often associated with foodborne illness in humans. To create effective preharvest interventions, it is critical to understand which factors STEC strains use to colonize the gastrointestinal tract of cattle, which serves as the reservoir for these pathogens. Several colonization factors are known, but little is understood about initial STEC colonization factors. Our objective was to identify these factors via contrasting gene expression between nonpathogenic E. coli and STEC. Colonic explants were inoculated with nonpathogenic E. coli strain MG1655 or STEC strains (O26, O111, or O157), bacterial colonization levels were determined, and RNA was isolated and sequenced. STEC strains adhered to colonic explants at numerically but not significantly higher levels compared to MG1655. After incubation with colonic explants, flagellin (fliC) was upregulated (log2 fold-change = 4.0, p < 0.0001) in O157 STEC, and collectively, Lon protease (lon) was upregulated (log2 fold-change = 3.6, p = 0.0009) in STEC strains compared to MG1655. These results demonstrate that H7 flagellum and Lon protease may play roles in early colonization and could be potential targets to reduce colonization in cattle.

Download Full-text

Prevalence and molecular detection of shiga toxin producing Escherichia coli from diarrheic cattle

Journal of the Bangladesh Agricultural University ◽

10.3329/jbau.v14i1.30598 ◽

2016 ◽

Vol 14 (1) ◽

pp. 63-68 ◽

Cited By ~ 1

Author(s):

MM Akter ◽

S Majumder ◽

KH MNH Nazir ◽

M Rahman

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Molecular Detection ◽

Chain Reaction ◽

Specific Primers ◽

Fecal Samples ◽

E Coli ◽

Uremic Syndrome ◽

Polymerase Chain ◽

Positive Isolate

Shiga toxin-producing Escherichia coli (STEC) are zoonotically important pathogen which causes hemorrhagic colitis, diarrhea, and hemolytic uremic syndrome in animals and humans. The present study was designed to isolate and identify the STEC from fecal samples of diarrheic cattle. A total of 35 diarrheic fecal samples were collected from Bangladesh Agricultural University (BAU) Veterinary Teaching Hospital. The samples were primarily examined for the detection of E. coli by cultural, morphological and biochemical characteristics, followed by confirmation of the isolates by Polymerase Chain Reaction (PCR) using gene specific primers. Later, the STEC were identified among the isolated E. coli through detection of Stx-1 and Stx-2 genes using duplex PCR. Out of 35 samples, 25 (71.43%) isolates were confirmed to be associated with E. coli, of which only 7 (28%) isolates were shiga toxin producers, and all of them were positive for Stx-1. However, no Stx-2 positive isolate could be detected. From this study, it may be concluded that cattle can act as a reservoir of STEC which may transmit to human or other animals.J. Bangladesh Agril. Univ. 14(1): 63-68, June 2016

Download Full-text