The Two-Component Regulatory System TCS08 Is Involved in Cellobiose Metabolism ofStreptococcus pneumoniaeR6

Publisher Website
Google Scholar
Abstract
The two-component system TCS08 is one of the regulatory systems that is important for virulence ofStreptococcus pneumoniae. In order to investigate the TCS08 regulon, we have analyzed transcription profiles of mutants derived fromS. pneumoniaeR6 by microarray analysis. Since deletion mutants are often without a significant phenotype, we constructed a mutation in the histidine kinase HK08, T133P, in analogy to the phosphatase mutation T230P in the H box of theS. pneumoniaeCiaH kinase described recently (D. Zähner, K. Kaminski, M. van der Linden, T. Mascher, M. Merai, and R. Hakenbeck, J. Mol. Microbiol. Biotechnol. 4:211-216, 2002). In addition, a deletion mutation was constructed inrr08, encoding the cognate response regulator. The most heavily suppressed genes in thehk08mutant were spr0276 to spr0282, encoding a putative cellobiose phosphoenolpyruvate sugar phosphotransferase system (PTS). Whereas the R6 Smrparent strain and the Δrr08mutant readily grew on cellobiose, thehk08mutant and selected mutants with deletions in the PTS cluster did not, strongly suggesting that TCS08 is involved in the catabolism of cellobiose. Homologues of the TCS08 system were found in closely related streptococci and other gram-positive cocci. However, the genes spr0276 to spr0282, encoding the putative cellobiose PTS, represent a genomic island inS. pneumoniaeand homologues were found inStreptococcus gordoniionly, suggesting that this system might contribute to the pathogenicity potential of the pneumococcus.