Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/28/2007
Publication Date: 8/28/2007
Citation: Jesudhasan, P.R., Cepeda, M.L., Widmer, K., Dowd, S.E., Soni, K.A., Hume, M.E., Zhu, J., Pillai, S.D. 2007. DNA microarray analysis reveals crosstalk of Salmonella enterica serovar Typhimurium with AI-2 of Escherichia coli [abstract]. In: American Society for Microbiology Cell to Cell Communication in Bacteria Abstracts, October 7-10, 2007, Austin, Texas. No. 110A.
Technical Abstract: Quorum sensing, or cell-to-cell communication, is made possible by the production and sensing of small, extracellular chemical signals called autoinducers (AI). These autoinducers accumulate as the population density increases, and thereby help bacteria to regulate their behavior by promoting or repressing gene expression. Autoinducers-2 (AI-2) helps bacteria to survive in a multi-species environment. DNA microarray experiments were conducted on luxS mutant of Salmonella Typhimurium to study its gene regulation in the presence of condition media (CM) of its own wild type, and CM of Escherichia coli (environmental isolate #5). It was observed that in the presence of CM of Salmonella Typhimurium, 1143 genes were differentially expressed significantly (P<0.05) (504 repressed and 639 expressed). In the presence of CM of E. coli #5, 392 genes were observed to be differentially expressed (133 repressed and 259 expressed) significantly (P<0.05). It was found that all the genes in the pathogenicity island of luxS mutant of Salmonella Typhimurium were turned down (but few of them are P>0.05) in the presence of CM of E. coli, and CM of Salmonella Typhimurium. These experiments not only suggest that AI-2 acts as a master controller of genes in the pathogenicity island of Salmonella Typhimurium, but also that Salmonella Typhimurium could sense the AI-2 molecules produced by E. coli in a multi-species environment.