Salmonella biofilms: participation of the RcsCDB regulatory system

PÁEZ PAZ, IM; LECCESE, MC; PESCARETTI MM,; DELGADO MA,

Congreso; XIII Congreso Argentino de Microbiología General; 2018

SAMIGE

Biofilms are described as polymeric matrix of extracellular substances in which the microorganisms are embedded, and attached to a living or artificial surface. It has been reported that the RcsCDB regulatory system participate in biofilm development. This system respond to cell surface stresses affecting the membrane integrity and producing the system activation. Here, we studied the regulation of the Salmonella Typhimurium biofilm formation under different growth media and surfaces conditions. For this purpose, we used the transcriptional lacZY fusion expression to chromosomal bapA gene, a RcsB-dependent gene required for this bacterial lifestyle. The ß-galactosidase activity was quantified under LB, LB without salt (LBs-), LBs- supplemented with biliar salts, planktonic or biofilm cultures conditions. In addition, we test the bapA expression by ß-galactosidase activity from biofilm developed on glass and polystyrene surfaces. We observed that the dissimilar expression levels of bapA on different media, growth and contact-surface conditions are controlled by RcsCDB system. These findings contribute to the understanding of the biofilm development and the important role of the RcsCDB system in this bacterial phenotype.