Putrescine Supplementation Limits the Expansion of pks+ Escherichia coli and Tumor Development in the Colon.

Unlabelled: Escherichia coli that harbor the polyketide synthase (pks) genomic island produce colibactin and are associated with sporadic colorectal cancer development. Given the considerable prevalence of pks+ bacteria in healthy individuals, we sought to identify strategies to limit the growth and expansion of pks+ E. coli.

Elevated concentrations of polymyxin B elicit a biofilm-specific resistance mechanism in Vibrio cholerae.

Vibrio cholerae can form biofilms in the aquatic environment and in the human intestine, facilitating the release of hyper-infectious aggregates. Due to the increasing antibiotic resistance, alternatives need to be found. One of these alternatives is antimicrobial peptides, including polymyxin B (PmB).

The VxrAB two-component system is important for the polymyxin B-dependent activation of the type VI secretion system in O1 strain A1552.

The type VI secretion system (T6SS) is used by bacteria for virulence, resistance to grazing, and competition with other bacteria. We previously demonstrated that the role of the T6SS in interbacterial competition and in resistance to grazing is enhanced in in the presence of subinhibitory concentrations of polymyxin B. Here, we performed a global quantitative proteomic analysis and a targeted transcriptomic analysis of the T6SS-known regulators in grown with and without polymyxin B.

Experimental evolution of identifies hypervesiculation as a way to increase motility in the presence of polymyxin B.

includes strains responsible for the cholera disease and is a natural inhabitant of aquatic environments. possesses a unique polar flagellum essential for motility, adhesion, and biofilm formation. In a previous study, we showed that motility and biofilm formation are altered in the presence of subinhibitory concentrations of polymyxin B in O1 and O139.

Secretome analysis reveals a role of subinhibitory concentrations of polymyxin B in the survival of Vibrio cholerae mediated by the type VI secretion system.

Antimicrobials are commonly used in prevention of infections including in aquaculture, agriculture and medicine. Subinhibitory concentrations of antimicrobial peptides can modulate resistance, virulence and persistence effectors in Gram-negative pathogens. In this study, we investigated the effect of subinhibitory concentrations of polymyxin B (PmB) on the secretome of Vibrio cholerae, a natural inhabitant of aquatic environments and the pathogen responsible for the cholera disease.

Flagella-dependent inhibition of biofilm formation by sub-inhibitory concentration of polymyxin B in Vibrio cholerae.

Biofilm formation is a common strategy used by bacteria in order to survive and persist in the environment. In Vibrio cholerae (V. cholerae), a Gram-negative pathogen responsible for the cholera disease, biofilm-like aggregates are important for the pathogenesis and disease transmission.

Limited Interactions between Streptococcus Suis and Haemophilus Parasuis in In Vitro Co-Infection Studies.

and are normal inhabitants of the porcine upper respiratory tract but are also among the most frequent causes of disease in weaned piglets worldwide, causing inflammatory diseases such as septicemia, meningitis and pneumonia. Using an in vitro model of infection with tracheal epithelial cells or primary alveolar macrophages (PAMs), it was possible to determine the interaction between serotype 2 and strains with different level of virulence. Within strains, the low-virulence F9 strain showed higher adhesion levels to respiratory epithelial cells and greater association levels to PAMs than the high-virulence Nagasaki strain.

The bias of experimental design, including strain background, in the determination of critical Streptococcus suis serotype 2 virulence factors.

Streptococcus suis serotype 2 is an important porcine bacterial pathogen and emerging zoonotic agent mainly responsible for sudden death, septic shock, and meningitis. However, serotype 2 strains are genotypically and phenotypically heterogeneous. Though a multitude of virulence factors have been described for S.

Recruitment of Factor H to the Streptococcus suis Cell Surface is Multifactorial.

Streptococcus suis is an important bacterial swine pathogen and a zoonotic agent. Recently, two surface proteins of S. suis, Fhb and Fhbp, have been described for their capacity to bind factor H-a soluble complement regulatory protein that protects host cells from complement-mediated damages.