Time-dependent gene expression pattern of Listeria monocytogenes J0161 in biofilms

Abstract

Time-dependent gene expression pattern of Listeria monocytogenes J0161 in biofilms Prem Saran Tirumalai, Soam PrakashEnvironmental and Advanced Parasitology Laboratory, Department of Zoology, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra, IndiaBackground: Listeria monocytogenes J0161, a food-borne pathogen, forms biofilm on contact surfaces, which makes the bacterium highly resistant. Biofilm formation in vivo confers resistance to antimicrobial agents, and in vitro not only increases resistance but also increases the risk of transmission of the pathogen. Biofilm formation is a complex dynamic process. The mechanism of biofilm formation is not as yet well understood. Understanding the molecular mechanism of biofilm formation will be of significance in removal of biofilms, thereby reducing the risk of transmission.Methods: L. monocytogenes cultures were grown to form biofilms on glass slides. At time intervals of 4, 12, and 24 hours, the cells were pelleted and the RNA extracted. The extracted RNA was analyzed using microarray technique and statistical tools.Results: The microarray data showed that gene expression was specifically upregulated at each time interval. About 159, 40, and 184 genes were upregulated at 4, 12, and 24 hours, respectively. An ascending and descending pattern of gene upregulation was identified.Conclusion: We report specific genes for biofilm growth of L. monocytogenes that were upregulated at particular time intervals. The role of specific genes in the formation of biofilms by L. monocytogenes J0161 can be studied using these data.Keywords: Listeria monocytogenes, microarray, biofilms, gene expression