Commensal Flora Reduce E. coli O157:H7 and Shiga Toxin in Mouse Intestine

2006 ◽  
Vol 1 (4) ◽  
pp. 193-193
Keyword(s):  
Shiga Toxin ◽  
E Coli ◽  
Commensal Flora ◽  
Mouse Intestine

scholarly journals Commensal Bacteria Influence Escherichia coli O157:H7 Persistence and Shiga Toxin Production in the Mouse Intestine

2006 ◽  
Vol 74 (3) ◽  
pp. 1977-1983 ◽  
Author(s):  
Shantini D. Gamage ◽  
Angela K. Patton ◽  
Jane E. Strasser ◽  
Claudia L. Chalk ◽  
Alison A. Weiss
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Toxin Production ◽  
Commensal Bacteria ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Commensal Flora ◽  
Mouse Intestine

ABSTRACT The presence of commensal flora reduced colonization of Escherichia coli O157:H7 and production of Shiga toxin (Stx) in the murine intestine. Stx production was not detected in mice colonized with E. coli that were resistant to the Shiga toxin phage, but it was detected in mice colonized with phage-susceptible E. coli.

scholarly journals Short-Tailed Stx Phages Exploit the Conserved YaeT Protein To Disseminate Shiga Toxin Genes among Enterobacteria

2007 ◽  
Vol 189 (20) ◽  
pp. 7223-7233 ◽  
Author(s):  
Darren L. Smith ◽  
Chloë E. James ◽  
Martin J. Sergeant ◽  
Yan Yaxian ◽  
Jon R. Saunders ◽  
...  
Keyword(s):  
Shiga Toxin ◽  
Bacterial Species ◽  
Erwinia Carotovora ◽  
Underlying Mechanism ◽  
Toxin Production ◽  
E Coli ◽  
Phage Adsorption ◽  
Commensal Flora ◽  
Conserved Gene

ABSTRACT Infection of Escherichia coli by Shiga toxin-encoding bacteriophages (Stx phages) was the pivotal event in the evolution of the deadly Shiga toxin-encoding E. coli (STEC), of which serotype O157:H7 is the most notorious. The number of different bacterial species and strains reported to produce Shiga toxin is now more than 500, since the first reported STEC infection outbreak in 1982. Clearly, Stx phages are spreading rapidly, but the underlying mechanism for this dissemination has not been explained. Here we show that an essential and highly conserved gene product, YaeT, which has an essential role in the insertion of proteins in the gram-negative bacterial outer membrane, is the surface molecule recognized by the majority (ca. 70%) of Stx phages via conserved tail spike proteins associated with a short-tailed morphology. The yaeT gene was initially identified through complementation, and its role was confirmed in phage binding assays with and without anti-YaeT antiserum. Heterologous cloning of E. coli yaeT to enable Stx phage adsorption to Erwinia carotovora and the phage adsorption patterns of bacterial species possessing natural yaeT variants further supported this conclusion. The use of an essential and highly conserved protein by the majority of Stx phages is a strategy that has enabled and promoted the rapid spread of shigatoxigenic potential throughout multiple E. coli serogroups and related bacterial species. Infection of commensal bacteria in the mammalian gut has been shown to amplify Shiga toxin production in vivo, and the data from this study provide a platform for the development of a therapeutic strategy to limit this YaeT-mediated infection of the commensal flora.

scholarly journals Utilizing the Food–Pathogen Metabolome to Putatively Identify Biomarkers for the Detection of Shiga Toxin-Producing E. coli (STEC) from Spinach

Metabolites ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 67
Author(s):  
Snehal R. Jadhav ◽  
Rohan M. Shah ◽  
Avinash V. Karpe ◽  
Robert S. Barlow ◽  
Kate E. McMillan ◽  
...  
Keyword(s):  
Shiga Toxin ◽  
Metabolic Profiling ◽  
Biomarker Discovery ◽  
Risk Groups ◽  
Proof Of Concept ◽  
Rapid Methods ◽  
E Coli ◽  
Leafy Greens ◽  
Food Pathogen ◽  
Genomic Similarity

Shiga toxigenic E. coli (STEC) are an important cause of foodborne disease globally with many outbreaks linked to the consumption of contaminated foods such as leafy greens. Existing methods for STEC detection and isolation are time-consuming. Rapid methods may assist in preventing contaminated products from reaching consumers. This proof-of-concept study aimed to determine if a metabolomics approach could be used to detect STEC contamination in spinach. Using untargeted metabolic profiling, the bacterial pellets and supernatants arising from bacterial and inoculated spinach enrichments were investigated for the presence of unique metabolites that enabled categorization of three E. coli risk groups. A total of 109 and 471 metabolite features were identified in bacterial and inoculated spinach enrichments, respectively. Supervised OPLS-DA analysis demonstrated clear discrimination between bacterial enrichments containing different risk groups. Further analysis of the spinach enrichments determined that pathogen risk groups 1 and 2 could be easily discriminated from the other groups, though some clustering of risk groups 1 and 2 was observed, likely representing their genomic similarity. Biomarker discovery identified metabolites that were significantly associated with risk groups and may be appropriate targets for potential biosensor development. This study has confirmed that metabolomics can be used to identify the presence of pathogenic E. coli likely to be implicated in human disease.

W1780 Ciprofloxacin in Rabbits Infected with a Shiga-Toxin (Stx)-Producing E. coli (Stec) Srain Leads to Worse Clinical Outcome and Increased Toxin Release

2008 ◽  
Vol 134 (4) ◽  
pp. A-714
Author(s):  
Antonio Serna ◽  
Chengru Zhu ◽  
Amelia J. Nugent ◽  
Erin K. Okeefe ◽  
Edgar Boedeker
Keyword(s):  
Clinical Outcome ◽  
Shiga Toxin ◽  
E Coli

scholarly journals Hemoconcentration and predictors in Shiga toxin-producing E. coli-hemolytic uremic syndrome (STEC-HUS)

2021 ◽  
Author(s):  
Sebastian Loos ◽  
Jun Oh ◽  
Laura van de Loo ◽  
Markus J. Kemper ◽  
Martin Blohm ◽  
...  
Keyword(s):  
Risk Factor ◽  
Serum Creatinine ◽  
Hemolytic Uremic Syndrome ◽  
Shiga Toxin ◽  
Neurological Symptoms ◽  
Fluid Loss ◽  
Good Prediction ◽  
E Coli ◽  
Complicated Course ◽  
Uremic Syndrome

Abstract Background Hemoconcentration has been identified as a risk factor for a complicated course in Shiga toxin-producing E. coli-hemolytic uremic syndrome (STEC-HUS). This single-center study assesses hemoconcentration and predictors at presentation in STEC-HUS treated from 2009–2017. Methods Data of 107 pediatric patients with STEC-HUS were analyzed retrospectively. Patients with mild HUS (mHUS, definition: max. serum creatinine < 1.5 mg/dL and no major neurological symptoms) were compared to patients with severe HUS (sHUS, definition: max. serum creatinine ≥ 1.5 mg/dL ± major neurological symptoms). Additionally, predictors of complicated HUS (dialysis ± major neurological symptoms) were analyzed. Results Sixteen of one hundred seven (15%) patients had mHUS. Admission of patients with sHUS occurred median 2 days earlier after the onset of symptoms than in patients with mHUS. On admission, patients with subsequent sHUS had significantly higher median hemoglobin (9.5 g/dL (3.6–15.7) vs. 8.5 g/dL (4.2–11.5), p = 0.016) than patients with mHUS. The product of hemoglobin (g/dL) and LDH (U/L) (cutoff value 13,302, sensitivity 78.0%, specificity of 87.5%) was a predictor of severe vs. mild HUS. Creatinine (AUC 0.86, 95% CI 0.79–0.93) and the previously published score hemoglobin (g/dL) + 2 × creatinine (mg/dL) showed a good prediction for development of complicated HUS (AUC 0.87, 95% CI 0.80–0.93). Conclusions At presentation, patients with subsequent severe STEC-HUS had a higher degree of hemoconcentration. This underlines that fluid loss or reduced fluid intake/administration may be a risk factor for severe HUS. The good predictive value of the score hemoglobin (g/dL) + 2 × creatinine (mg/dL) for complicated HUS could be validated in our cohort. Graphical abstract

scholarly journals Independent Behavior of Commensal Flora for Carriage of Fluoroquinolone-Resistant Bacteria in Patients at Admission

2010 ◽  
Vol 54 (12) ◽  
pp. 5193-5200 ◽  
Author(s):  
Victoire de Lastours ◽  
Françoise Chau ◽  
Florence Tubach ◽  
Blandine Pasquet ◽  
Etienne Ruppé ◽  
...  
Keyword(s):  
Risk Factors ◽  
Bacterial Resistance ◽  
Care Facility ◽  
Health Care Facility ◽  
Epidemiological Data ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
E Coli ◽  
Commensal Flora ◽  
Resistant Strains

ABSTRACT The important role of commensal flora as a natural reservoir of bacterial resistance is now well established. However, whether the behavior of each commensal flora is similar to that of other floras in terms of rates of carriage and risk factors for bacterial resistance is unknown. During a 6-month period, we prospectively investigated colonization with fluoroquinolone-resistant bacteria in the three main commensal floras from hospitalized patients at admission, targeting Escherichia coli in the fecal flora, coagulase-negative Staphylococcus (CNS) in the nasal flora, and α-hemolytic streptococci in the pharyngeal flora. Resistant strains were detected on quinolone-containing selective agar. Clinical and epidemiological data were collected. A total of 555 patients were included. Carriage rates of resistance were 8.0% in E. coli, 30.3% in CNS for ciprofloxacin, and 27.2% in streptococci for levofloxacin; 56% of the patients carried resistance in at least one flora but only 0.9% simultaneously in all floras, which is no more than random. Risk factors associated with the carriage of fluoroquinolone-resistant strains differed between fecal E. coli (i.e., colonization by multidrug-resistant bacteria) and nasal CNS (i.e., age, coming from a health care facility, and previous antibiotic treatment with a fluoroquinolone) while no risk factors were identified for pharyngeal streptococci. Despite high rates of colonization with fluoroquinolone-resistant bacteria, each commensal flora behaved independently since simultaneous carriage of resistance in the three distinct floras was uncommon, and risk factors differed. Consequences of environmental selective pressures vary in each commensal flora according to its local specificities (clinical trial NCT00520715 [http://clinicaltrials.gov/ct2/show/NCT00520715 ]).

Renal complement deposition in a mouse model of Shiga toxin-producing E. coli infection

2013 ◽  
Vol 56 (3) ◽  
pp. 286
Author(s):  
J. Rebetz ◽  
Z. Békássy ◽  
D. Karpman
Keyword(s):  
Mouse Model ◽  
Shiga Toxin ◽  
E Coli ◽  
Complement Deposition

Prevalence of non-O157 Shiga Toxin-producing E. Coli in Children and Calves in Al- Muthanna Province, Iraq

2021 ◽  
Vol 14 (2) ◽  
pp. 78-90
Author(s):  
Ahmed Jarad ◽  
Kh. Al- Jeboori
Keyword(s):  
Shiga Toxin ◽  
Latex Agglutination ◽  
Macconkey Agar ◽  
Biochemical Tests ◽  
Bacteriological Study ◽  
E Coli ◽  
Additional Information ◽  
Single Colony ◽  
Big Six ◽  
Reliable Isolation

The present study focus on non-O157 Shiga toxin-producing E. Coli (STEC), included a bacteriological study was subjected to provide additional information for non-O157 STEC prevalence in children and calves. Isolation by using selective culturing media (CHROMagar STEC and CHROMagar O157) from 127 children suffering from diarrhea and 133 calves in Al- Muthanna province. Characterization depends on culturing positive colony on MacConkey agar and Levin’s Eosin Methylene blue agar, staining single colony from the growth by gram stain, biochemical tests; Indole, the Methyl Red, Voges-Proskauer, Citrate test, Oxidase, Catalase, Urease, Motility, Kligler Iron and Api-20E, were done to confirm a diagnosis of non-O157 STEC, The reliable isolation as non-O157 STEC serotyping by specific latex agglutination test for the target non-O157 STEC (big six) serogroup (O26, O45, O103, O111, O121 and O145). The current study showed the prevalence of non-O157 STEC was 20 of out 127 (15.73%) in samples collected from children and 27 / 133 (20.30%) in calves samples in conclusion the Non-O157 STEC is an important cause of diarrhea in children, and calves; finally, the calves play an important reservoir for Non-O157 STEC.

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

2016 ◽  
Vol 5 (1) ◽  
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 <em>Escherichia coli</em> (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 <em>E. coli</em> O157 were isolated (2/161, 1.2%) but did not carry any virulence-associated genes and 22 <em>stx</em>-positive samples (22/146, 15.1%) were detected in enrichment cultures, mostly from ovine cheeses. Only two strains isolated from different ovine cheeses carried <em>stx</em> gene and none of these was <em>eae</em>-positive. This study confirms the presence of <em>stx</em>-positive <em>E. coli</em> and suggests that this type of food cannot be excluded as a potential vehicle of STEC.

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