A novel sRNA that modulates virulence and environmental fitness of Vibrio cholerae.

We recently described the discovery and initial functional characterization of a new sRNA, VrrA, in Vibrio cholerae O1 strain A1552. The VrrA homologs were found in all Vibrio strains whose genome sequences were reported at present. In this article, we summarize the multi-functional features of VrrA in V. cholerae pathogenesis and physiology, especially in relation to the regulation of outer membrane vesicle formation and its consequence in environmental adaptation of the bacterium. As the vrrA gene was not predicted by any of the previous bioinformatics-based genome-wide screenings for sRNA, we discuss the reasons and give suggestion on improving current bioinformatics tools.