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The genus Brucella comprises a monophyletic group including 6 classical species showing clonal evolution: B. abortus, B. suis, B. melitensis, B. canis, B. ovis, and B. neotomae (1,2). The zoonotic [...]

The 9th symposium on Antimicrobial Resistance in Animals and the Environment (ARAE) was held in Tours, France in July 2023, attracting 170 participants from 23 countries. The conference focused on various aspects of antibiotic resistance, including epidemiology, resistance mechanisms, microbiota, and whole genome sequencing. Research presented at the symposium covered topics such as polyether ionophore resistance, multidrug-resistant Salmonella, and methodologies for rapid typing of MDR bacterial isolates. The event also highlighted the need for harmonization in bacterial culture and identification methods in veterinary clinical laboratories. The proceedings of the symposium are available online, and the next edition of ARAE is scheduled for July 2025 in Berlin, Germany. [Extracted from the article]

This document is an editorial titled "Insights in infectious agents and disease: 2022" that provides an overview of recent developments in the field of bacterial, viral, and parasitic infectious diseases. It discusses major pandemics and epidemics caused by bacterial and viral diseases, including zoonotic pathogens transmitted from animals to humans. The editorial highlights various topics covered in research articles published in the journal, such as pathogenesis, antimicrobial resistance, epidemiology, diagnosis, and vaccine development. The document focuses on bats as reservoirs of zoonotic pathogens, diagnostic methods for identifying pathogens, vaccine development, and viral and parasitic infections. It emphasizes the importance of understanding microorganisms hosted by bats and the need for effective diagnostic strategies. The document also explores vaccine development for diseases like bubonic plague and COVID-19, as well as the pathogenesis of viral infections in reservoir hosts and specific infections caused by parasites. It concludes by highlighting ongoing research and advancements in the field of infectious diseases. [Extracted from the article]

Bile represses Salmonella enterica serovar Typhimurium (S. Typhimurium) intestinal cell invasion, but it remains unclear which bile components and mechanisms are implicated. Previous studies reported that bile inhibits the RamR binding to the ramA promoter, resulting in ramA increased transcription, and that ramA overexpression is associated to decreased expression of type III secretion system1 (TTSS-1) invasion genes and to impaired intestinal cell invasiveness in S. Typhimurium. In this study, we assessed the possible involvement of the ramRA multidrug efflux regulatory locus and individual bile salts in the bile-mediated repression of S. Typhimuriuminvasion, using Caco-2 intestinal epithelial cells and S. Typhimurium strain ATCC 14028s. Our results indicate that (i) major primary bile salts, chenodeoxycholate and its conjugated-derivative salts, cholate, and deoxycholate, activate ramA transcription in a RamR-dependent manner, and (ii) it results in repression of hilA, encoding themaster activator of TTSS-1 genes, and as a consequence in the repression of cellular invasiveness. On the other hand, crude ox bile extract and cholate were also shown to repress the transcription of hilA independently of RamR, and to inhibit cell invasion independently of ramRA. Altogether, these data suggest that bile-mediated repression of S. Typhimurium invasion occurs through pleiotropic effects involving partly ramRA, as well as other unknown regulatory pathways. Bile components other than the bile salts used in this study might also participate in this phenomenon. [ABSTRACT FROM AUTHOR]

We document an increase in the number of multidrugresistant Salmonella enterica serovar Paratyphi B [dT.sup.*] identified in Canada. Most of these strains harbor Salmonella genomic island 1 (SGI1). Further studies [...]

Salmonella genomic island 1 (SGI1) contains an antibiotic resistance gene cluster and has been previously identified in multidrug-resistant Salmonella enterica serovars Typhimurium DT104, Agona, and Paratyphi B. We identified a [...]

We have identified Salmonella genomic island I (SGI1) in an isolate of Salmonella enterica serotype Paratyphi B. This antibiotic-resistance gene cluster, which confers multidrug resistance, has been previously identified in [...]

Research has been conducted on the Salmonella genomic island 1. The characterization of this genomic island which harbors the genes associated with the phenotype in a Salmonella enterica serovar Typhimurium DT104 Canadian isolate has been carried out and discussed.

Results show that variations in Omp2a and Omp2b porin sequences among species of Brucella are brought about by multiple gene conversion between cognate genes. However, the porin variations are not reflected in any major antigenic variability, suggesting the variations may be due to conductivity modifications in the porins.