Dam enzyme participates in the regulation of biofilm production in Salmonella enterica serovar Typhimurium

AYA CASTAÑEDA, MR; SARNACKI SH; NOTO LLANA M; GIACOMODONATO MN; CERQUETTI MC

Jena

Congreso; 5th International Student Conference on Microbial Communication.; 2015

On the bacterial world, existence within surface-associated structured multicellular communities may be the rule, rather than the exception. It has beendemonstrated that several serovars of S. enterica, including Typhimurium, are able to attach to and form biofilms on a variety of surfaces, and this ability has been implicatedin the persistence of non-typhoidal Salmonella in the environment and in industrial, veterinary and medical settings. Non-typhoidal salmonellosis is an important foodbornedisease of worldwide economic significance. Salmonella Typhimurium (S.T) can be found in some laying flocks in the European Union (EU) and in earlier years, has beenassociated with outbreaks involving contamination of egg contents. Here, we studied the involvement of DNA adenine methyltransferase (Dam) methylations in biofilmproduction in S.T strains. The ability to generate biofilms and the expression of curli and cellulose were analyzed in wild type and mutant strains. Also, the expression of fivemain genes that are involved on biofilm production -csgD, csgA, bcsA, adrA and bapA- was determined by qPCR, in different culture conditions. We observed that damdefectivestrains of S.T are impaired in their capacity to develop biofilms and that the production of cellulose and curli are affected, mainly curli production. Our results suggestthat changes in gene expression required for biofilm production are finely regulated by Dam methylation. Thus, methylations could modulate csgD expression and up regulatethe expression of factors related with biofilm production, including biofilm-associated proteins, curli and cellulose. Biofilm production plays an important role in bacterialinfectious process and this study contributes to the understanding of biofilm regulation in Salmonella