Work

Catabolite Control Protein A Controls Hydrogen Peroxide Production and Cell Death inStreptococcus sanguinis

Year: 2010

Type: article

Abstract: Streptococcus sanguinis is a commensal oral bacterium producing hydrogen peroxide (H₂O₂) that is dependent on pyruvate oxidase (Spx) activity. In addition to its well-known role in bacterial antagonism during interspecies competition, H₂O₂ causes cell death in about 10% of the S. sanguinis population. As a consequence of H₂O₂-induced cell death, largely intact chromosomal DNA is released into the environment. This extracellular DNA (eDNA) contributes to the self-aggregation phenotype under aerobic conditions. To further investigate the regulation of spx gene expression, we assessed the role of catabolite control protein A (CcpA) in spx expression control. We report here that CcpA represses spx expression. An isogenic ΔccpA mutant showed elevated spx expression, increased Spx abundance, and H₂O₂ production, whereas the wild type did not respond with altered spx expression in the presence of glucose and other carbohydrates. Since H₂O₂ is directly involved in the release of eDNA and bacterial cell death, the presented data suggest that CcpA is a central control element in this important developmental process in S. sanguinis.

Source: Journal of Bacteriology

DOI: 10.1128/jb.01131-10

Authors: Lanyan Zheng, Zhijun Chen, Andreas Itzek, Michael Ashby, Jens Kreth

Institutions: University of Oklahoma Health Sciences Center, China Medical University, University of Oklahoma

Language: English

Topic: Bacterial Genetics and Biotechnology

Subfield: Genetics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: National Institutes of Health, National Institute of Dental and Craniofacial Research

Awards: Interspecies Streptococcal Antagonisms in Oral Biofilms, G4238641180, Inorganic Antimicrobials in Exocrine Fluids, G5028918003