The quorum sensing molecule C12-HSL promotes biofilm formation and increases adrA expression in Salmonella Enteritidis under anaerobic conditions

Acyl-homoserine lactones (AHLs) are quorum-sensing signaling molecules in Gram-negative bac-teria and positively regulate biofilm formation in Salmonella under specific conditions. In this study, biofilm formation in Salmonella enterica was evaluated at 28 and 37 C-degrees, under aerobic and anaerobic conditions. Additionally, the influence of the N-dodecanoyl-DL-homoserine lac-tone (C12-HSL) on biofilm formation and the expression of genes related to the synthesis of structural components, regulation, and quorum sensing was assessed under anaerobiosis at 28 and 37 C-degrees. Biofilm formation was found not to be influenced by the atmospheric conditions at 28(degrees)C. However, it was reduced at 37(degrees)C under anaerobiosis. C12-HSL enhanced biofilm forma-tion at 37 C-degrees under anaerobiosis and increased the expression of the adrA and luxS genes, sug-gesting an increase in c-di-GMP, a second messenger that controls essential physiological functions in bacteria. These results provide new insights into the regulation of biofilm formation in Salmonella under anaerobic conditions.