Wild Boars as Reservoir of Highly Virulent Clone of Hybrid Shiga Toxigenic and Enterotoxigenic Escherichia coli Responsible for Edema Disease, France

AbstractEnteric infections caused by the gram-negative bacteria enterotoxigenic Escherichia coli (ETEC), Vibrio cholerae, Shigella flexneri, and Salmonella enterica are among the most common and affect billions of people each year. These bacteria control expression of virulence factors using a network of transcriptional regulators, some of which are modulated by small molecules as has been shown for ToxT, an AraC family member from V. cholerae. In ETEC the expression of many types of adhesive pili is dependent upon the AraC family member Rns. We present here the 3 Å crystal structure of Rns and show it closely resembles ToxT. Rns crystallized as a dimer via an interface similar to that observed in other dimeric AraC’s. Furthermore, the structure of Rns revealed the presence of a ligand, decanoic acid, that inhibits its activity in a manner similar to the fatty acid mediated inhibition observed for ToxT and the S. enterica homologue HilD. Together, these results support our hypothesis that fatty acids regulate virulence controlling AraC family members in a common manner across a number of enteric pathogens. Furthermore, for the first time this work identifies a small molecule capable of inhibiting the ETEC Rns regulon, providing a basis for development of therapeutics against this deadly human pathogen.

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Designing and determining immunogenicity of a recombinant protein due to producing a new vaccine against Enterotoxigenic Escherichia coli containing CfaE and CotD subunits

Journal of Immunoassay and Immunochemistry ◽

10.1080/15321819.2021.1906890 ◽

2021 ◽

pp. 1-18

Author(s):

Pooneh Roghanian ◽

Shohreh Zare Karizi ◽

Mohammad Javad Motamedi ◽

Rouhollah Kazemi ◽

Dorna Khoobbakht ◽

...

Keyword(s):

Escherichia Coli ◽

Recombinant Protein ◽

Enterotoxigenic Escherichia Coli

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Deletion of FaeG alleviated Enterotoxigenic Escherichia coli F4ac-induced apoptosis in the intestine

AMB Express ◽

10.1186/s13568-021-01201-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Pengpeng Xia ◽

Yunping Wu ◽

Siqi Lian ◽

Guomei Quan ◽

Yiting Wang ◽

...

Keyword(s):

Escherichia Coli ◽

Clinical Symptoms ◽

Mucosal Damage ◽

Enterotoxigenic Escherichia Coli ◽

Intestinal Epithelial ◽

Antibody Microarray ◽

E Coli ◽

Fimbrial Subunit ◽

Induced Apoptosis ◽

Weaning Piglets

AbstractEnterotoxigenic Escherichia coli (ETEC) F4ac is a major constraint to the development of the pig industry, which is causing newborn and post-weaning piglets diarrhea. Previous studies proved that FaeG is the major fimbrial subunit of F4ac E. coli and efficient for bacterial adherence and receptor recognition. Here we show that the faeG deletion attenuates both the clinical symptoms of F4ac infection and the F4ac-induced intestinal mucosal damage in piglets. Antibody microarray analysis and the detection of mRNA expression using porcine neonatal jejunal IPEC-J2 cells also determined that the absence of FaeG subunit alleviated the F4ac promoted apoptosis in the intestinal epithelial cells. Thus, targeted depletion of FaeG is still beneficial for the prevention or treatment of F4ac infection.

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Seaweed polysaccharide mitigates intestinal barrier dysfunction induced by enterotoxigenic Escherichia coli through NF‐κB pathway suppression in porcine intestinal epithelial cells

Journal of Animal Physiology and Animal Nutrition ◽

10.1111/jpn.13540 ◽

2021 ◽

Author(s):

Xiaobo Guo ◽

Jun Chen ◽

Jin Yang ◽

Qin He ◽

Bowen Luo ◽

...

Keyword(s):

Escherichia Coli ◽

Epithelial Cells ◽

Intestinal Epithelial Cells ◽

Intestinal Barrier ◽

Enterotoxigenic Escherichia Coli ◽

Intestinal Epithelial ◽

Barrier Dysfunction ◽

Intestinal Barrier Dysfunction

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Immunogenicity and protective efficacy of enterotoxigenic Escherichia coli (ETEC) total RNA against ETEC challenge in a mouse model

Scientific Reports ◽

10.1038/s41598-020-77551-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mandi Liu ◽

Yue Zhang ◽

Di Zhang ◽

Yun Bai ◽

Guomei Liu ◽

...

Keyword(s):

Escherichia Coli ◽

Mouse Model ◽

Immune Responses ◽

Protective Efficacy ◽

Enterotoxigenic Escherichia Coli ◽

Economic Losses ◽

Th2 Response ◽

Total Rna ◽

Etec Infection

AbstractEnterotoxigenic Escherichia coli (ETEC), an essential cause of post-weaning diarrhea (PWD) in piglets, leads to significant economic losses to the pig industry. The present study aims to identify the role of ETEC total RNA in eliciting immune responses to protect animals against ETEC infection. The results showed that the total RNA isolated from pig-derived ETEC K88ac strain effectively stimulated the IL-1β secretion of porcine intestinal epithelial cells (IPEC-J2). The mouse model immunized with ETEC total RNA via intramuscular injection (IM) or oral route (OR) was used to evaluate the protective efficiency of the ETEC total RNA. The results suggested that 70 μg ETEC total RNA administered by either route significantly promoted the production of the serum IL-1β and K88ac specific immunoglobulins (IgG, IgM, and IgA). Besides, the ETEC RNA administration augmented strong mucosal immunity by elevating K88ac specific IgA level in the intestinal fluid. Intramuscularly administered RNA induced a Th1/Th2 shift toward a Th2 response, while the orally administered RNA did not. The ETEC total RNA efficiently protected the animals against the ETEC challenge either by itself or as an adjuvant. The histology characterization of the small intestines also suggested the ETEC RNA administration protected the small intestinal structure against the ETEC infection. Particularly of note was that the immunity level and protective efficacy caused by ETEC RNA were dose-dependent. These findings will help understand the role of bacterial RNA in eliciting immune responses, and benefit the development of RNA-based vaccines or adjuvants.

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Detection of Beta-Lactam-Resistant Escherichia coli and Toxigenic Clostridioides difficile Strains in Wild Boars Foraging in an Anthropization Gradient

Animals ◽

10.3390/ani11061585 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1585

Author(s):

Laila Darwich ◽

Chiara Seminati ◽

Jorge R. López-Olvera ◽

Anna Vidal ◽

Laia Aguirre ◽

...

Keyword(s):

Escherichia Coli ◽

Disease Transmission ◽

Urban Areas ◽

Carbapenem Resistance ◽

Anthropogenic Sources ◽

Health Concern ◽

Natural Environments ◽

Beta Lactam ◽

Wild Boars ◽

Clostridioides Difficile

Disease transmission among wild boars, domestic animals and humans is a public health concern, especially in areas with high wild boar densities. In this study, fecal samples of wild boars (n = 200) from different locations of the Metropolitan Area of Barcelona were analyzed by PCR to explore the frequency of β-lactamases and extended cephalosporin and carbapenem resistance genes (ESBLs) in Escherichia coli strains and the presence of toxigenic Clostridioides difficile. The prevalence of genes conferring resistance to β-lactam antimicrobials was 8.0% (16/200): blaCMY-2 (3.0%), blaTEM-1b (2.5%), blaCTX-M-14 (1.0%), blaSHV-28 (1.0%), blaCTX-M-15 (0.5%) and blaCMY-1 (0.5%). Clostridioides difficile TcdA+ was detected in two wild boars (1.0%), which is the first report of this pathogen in wild boars in Spain. Moreover, the wild boars foraging in urban and peri-urban locations were more exposed to AMRB sources than the wild boars dwelling in natural environments. In conclusion, the detection of E. coli carrying ESBL/AmpC genes and toxigenic C. difficile in wild boars foraging in urban areas reinforces the value of this game species as a sentinel of environmental AMRB sources. In addition, these wild boars can be a public and environmental health concern by disseminating AMRB and other zoonotic agents. Although this study provides the first hints of the potential anthropogenic sources of AMR, further efforts should be conducted to identify and control them.

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