IBR   13079
INSTITUTO DE BIOLOGIA MOLECULAR Y CELULAR DE ROSARIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Regulation of the Type VI Secretion System of Serratia marcescens: the role of the Rcs System
Autor/es:
MARTINA LAZZARO; ELEONORA GARCÍA VÉSCOVI
Lugar:
Mar del Plata
Reunión:
Congreso; LI Reunión de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB); 2015
Resumen:
Serratia marcescens is an opportunistic human pathogen that represents a growing problem for public health. It has been previously reported that the type VI secretion system (T6SS) of S. marcescens has a role in bacterial competition. This characteristic may provide an important competitive advantage against other bacteria in the host or in environmental niches. However, little is known about its regulation. In this work, we analyze the regulation of the T6SS of S. marcescens. We propose that this system is regulated by the Rcs system. We found that the rcsB mutant strain shows a lower antibacterial activity than the wild type strain. This observation is also supported by immunodetection assays, which shows lower levels of Hcp (a structural component of the T6SS) in the rcsB mutant. In addition, we have found a putative RcsB binding site in the promoter region of the cluster that codes for the components of T6SS. Using a fusion to GFP as a reporter of the transcriptional activity of that promoter, we havedetermined that the level of transcriptional activity in the rcsB mutant strain is lower than in the wild type strain. In agreement with this result, we have done real-time PCR assays and we have found that the level of transcript of T6SSis lower in the rcsB mutant. Together, our results show that, in S. marcescens, the Rcs system regulates the T6SS at the transcriptional level.