Microarray-based identification of htrA, a Streptococcus pneumoniae gene that is regulated by the CiaRH two-component system and contributes to nasopharyngeal colonization.

Bacteriocin activity of Streptococcus pneumoniae is controlled by the serine protease HtrA via posttranscriptional regulation.

The blp locus of a type 6A strain of Streptococcus pneumoniae encodes a two-peptide bacteriocin, pneumocin MN, which mediates intraspecies competition during mouse nasopharyngeal colonization. This locus is regulated by a quorum-sensing mechanism consisting of a dedicated two-component regulatory system and a peptide pheromone. Like most clinical isolates, this type 6A strain can be separated i...

Pneumococcal HtrA protease mediates inhibition of competence by the CiaRH two-component signaling system.

Activation of the CiaRH two-component signaling system prevents the development of competence for genetic transformation in Streptococcus pneumoniae through a previously unknown mechanism. Earlier studies have shown that CiaRH controls the expression of htrA, which we show encodes a surface-expressed serine protease. We found that mutagenesis of the putative catalytic serine of HtrA, while not ...

Evaluation of Prevalence of S. pneumoniae pharyngeal carriers under 5 years of age by lytA gene detection

ABSTRACT          Background and Objective: Streptococcus pneumoniae is one of the leading causes of death among children worldwide. Nasopharyngeal colonization in children can spread pneumococcal infections in the community. This study aimed to evaluate the prevalence of S. pneumoniae strains isolated from healthy pharyngeal carriers less than 5 yea...

Two-Component Signaling System Inhibition of Competence by the CiaRH Pneumococcal HtrA Protease Mediates

Control of competence by related non-coding csRNAs in Streptococcus pneumoniae R6

The two-component regulatory system CiaRH of Streptococcus pneumoniae is involved in β-lactam resistance, maintenance of cell integrity, bacteriocin production, host colonization, virulence, and competence. The response regulator CiaR controls, among other genes, expression of five highly similar small non-coding RNAs, designated csRNAs. These csRNAs control competence development by targeting ...