RegR, a global LacI/GalR family regulator, modulates virulence and competence in Streptococcus pneumoniae.

ABSTRACT: The homolactic and catalase-deficient pathogen Streptococcus pneumoniae is not only tolerant to oxygen but requires the activity of its NADH oxidase, Nox, to develop optimal virulence and competence for genetic transformation. In this work, we show that the global regulator RegR is also involved in these traits. Genetic dissection revealed that RegR regulates competence and the expression of virulence factors, including hyaluronidase. In bacteria grown in vitro, RegR represses hyaluronidase. At neutral pH, it increases adherence to A549 epithelial cells, and at alkaline pH, it acts upstream of the CiaRH two-component signaling system to activate competence. These phenotypes are not associated with changes in antibiotic resistance, central metabolism, and carbohydrate utilization. Although

SUBMITTER: Chapuy-Regaud S 

PROVIDER: S-EPMC153264 | biostudies-literature | 2003 May

REPOSITORIES: biostudies-literature