Stability of and 669 Probiotic Strains When Added to Different Feed Matrices Used in Dairy Production.

Few data are available evaluating the stability of direct-fed microbials (DFM) following their inclusion in different feed matrices. Therefore, six Exp. evaluated the recovery of bacilli spores (BOVACILLUS; Exp.

Transcriptional analysis reveals specific niche factors and response to environmental stresses of enterohemorrhagic Escherichia coli O157:H7 in bovine digestive contents.

Background: Enterohemorrhagic Escherichia coli (EHEC) are responsible for severe diseases in humans, and the ruminant digestive tract is considered as their main reservoir. Their excretion in bovine feces leads to the contamination of foods and the environment. Thus, providing knowledge of processes used by EHEC to survive and/or develop all along the bovine gut represents a major step for strategies implementation.

An Overview of the Elusive Passenger in the Gastrointestinal Tract of Cattle: The Shiga Toxin Producing .

For approximately 10,000 years, cattle have been our major source of meat and dairy. However, cattle are also a major reservoir for dangerous foodborne pathogens that belong to the Shiga toxin-producing (STEC) group. Even though STEC infections in humans are rare, they are often lethal, as treatment options are limited.

Transcriptomic analysis reveals specific metabolic pathways of enterohemorrhagic Escherichia coli O157:H7 in bovine digestive contents.

Background: The cattle gastrointestinal tract (GIT) is the main enterohemorrhagic Escherichia coli (EHEC) reservoir. In order to identify nutrients required for the survival or multiplication of EHEC in the bovine GIT, we compared the transcriptomes of the EHEC O157:H7 reference strain EDL933 cultured in vitro in bovine digestive contents (DCs) (rumen, small intestine and rectum) using RNA-sequencing.

Results: Gene expression profiles showed that EHEC EDL933 activated common but also specific metabolic pathways to survive in the different bovine DCs.

Aspartate metabolism is involved in the maintenance of enterohaemorrhagic Escherichia coli O157:H7 in bovine intestinal content.

The gastrointestinal tract (GIT) of healthy cattle is the main reservoir of enterohaemorrhagic Escherichia coli (EHEC). Therefore, it is crucial to better understand the physiology of EHEC in the bovine GIT. In this study, we demonstrate that aspartate present in bovine small intestine content (BSIC), was exhausted after incubation of the reference EHEC strain EDL933 but was poorly assimilated by the endogenous microbiota.

Factors Involved in the Persistence of a Shiga Toxin-Producing O157:H7 Strain in Bovine Feces and Gastro-Intestinal Content.

Healthy cattle are the primary reservoir for O157:H7 Shiga toxin-producing responsible for human food-borne infections. Because farm environment acts as a source of cattle contamination, it is important to better understand the factors controlling the persistence of O157:H7 outside the bovine gut. The O157:H7 strain MC2, identified as a persistent strain in French farms, possessed the characteristics required to cause human infections and genetic markers associated with clinical O157:H7 isolates.

Lactobacillus reuteri suppresses E. coli O157:H7 in bovine ruminal fluid: Toward a pre-slaughter strategy to improve food safety?

The bovine gastrointestinal tract (GIT) is the main reservoir for enterohaemorrhagic Escherichia coli (EHEC) responsible for food-borne infections. Therefore, it is crucial to develop strategies, such as EHEC suppression by antagonistic microorganisms, to reduce EHEC survival in the GIT of cattle and to limit shedding and food contamination. Most human-derived Lactobacillus reuteri strains produce hydroxypropionaldehyde (HPA), an antimicrobial compound, during anaerobic reduction of glycerol.

Draft genome sequence and characterization of commensal strain BG1 isolated from bovine gastro-intestinal tract.

is the most abundant facultative anaerobic bacteria in the gastro-intestinal tract of mammals but can be responsible for intestinal infection due to acquisition of virulence factors. Genomes of pathogenic strains are widely described whereas those of bovine commensal strains are very scarce. Here, we report the genome sequence, annotation, and features of the commensal BG1 isolated from the gastro-intestinal tract of cattle.

Draft Genome Sequence of Enterohemorrhagic O157:H7 Strain MC2 Isolated from Cattle in France.

Enterohemorrhagic (EHEC) with serotype O157:H7 is a major foodborne pathogen. Here, we report the draft genome sequence of EHEC O157:H7 strain MC2 isolated from cattle in France. The assembly contains 5,400,376 bp that encoded 5,914 predicted genes (5,805 protein-encoding genes and 109 RNA genes).

The Serine Protease EspC from Enteropathogenic Escherichia coli Regulates Pore Formation and Cytotoxicity Mediated by the Type III Secretion System.

Type III secretion systems (T3SSs) are specialized macromolecular machines critical for bacterial virulence, and allowing the injection of bacterial effectors into host cells. The T3SS-dependent injection process requires the prior insertion of a protein complex, the translocon, into host cell membranes consisting of two-T3SS hydrophobic proteins, associated with pore-forming activity. In all described T3SS to date, a hydrophilic protein connects one hydrophobic component to the T3SS needle, presumably insuring the continuum between the hollow needle and the translocon.

Pathogenic Neisseria meningitidis utilizes CD147 for vascular colonization.

Neisseria meningitidis is a cause of meningitis epidemics worldwide and of rapidly progressing fatal septic shock. A crucial step in the pathogenesis of invasive meningococcal infections is the adhesion of bloodborne meningococci to both peripheral and brain endothelia, leading to major vascular dysfunction. Initial adhesion of pathogenic strains to endothelial cells relies on meningococcal type IV pili, but the endothelial receptor for bacterial adhesion remains unknown.