Biogenesis of outer membrane vesicles in Serratia marcescens is thermoregulated and can be induced by activation of the Rcs phosphorelay system.

Abstract

Outer membrane vesicles (OMVs) have been identified in a wide range of bacteria, yet little is known of their biogenesis. It has been proposed that OMVs can act as long-range toxin delivery vectors and as a novel stress response. We have found that the formation of OMVs in the gram-negative opportunistic pathogen Serratia marcescens is thermoregulated, with a significant amount of OMVs produced at 22 or 30°C and negligible quantities formed at 37°C under laboratory conditions. Inactivation of the synthesis of the enterobacterial common antigen (ECA) resulted in a hypervesiculation phenotype, supporting the hypothesis that OMVs are produced in response to stress. We demonstrate that the phenotype can be reversed to wild-type (WT) levels upon the loss of the Rcs phosphorelay response regulator RcsB, but not RcsA, suggesting a role for the Rcs phosphorelay in the production of OMVs. MS fingerprinting of the OMVs provided evidence of cargo selection within wild-type cells, suggesting a possible role for Serratia OMVs in toxin delivery. In addition, OMV-associated cargo proved toxic upon injection into the haemocoel of Galleria mellonella larvae. These experiments demonstrate that OMVs are the result of a regulated process in Serratia and suggest that OMVs could play a role in virulence.

DOI: 10.1128/JB.00016-12
0102030201520162017
Citations per Year

Citation Velocity: 10

Averaging 10 citations per year over the last 3 years.

Learn more about how we calculate this metric in our FAQ.

Cite this paper

@article{McMahon2012BiogenesisOO, title={Biogenesis of outer membrane vesicles in Serratia marcescens is thermoregulated and can be induced by activation of the Rcs phosphorelay system.}, author={Kenneth J McMahon and Mar{\'i}a Eugenia Castelli and Eleonora Garc{\'i}a V{\'e}scovi and Mario F Feldman}, journal={Journal of bacteriology}, year={2012}, volume={194 12}, pages={3241-9} }