Extracellular deoxyribonuclease made by group A Streptococcus assists pathogenesis by enhancing evasion of the innate immune response.

ABSTRACT: Many pathogenic bacteria produce extracellular DNase, but the benefit of this enzymatic activity is not understood. For example, all strains of the human bacterial pathogen group A Streptococcus (GAS) produce at least one extracellular DNase, and most strains make several distinct enzymes. Despite six decades of study, it is not known whether production of DNase by GAS enhances virulence. To test the hypothesis that extracellular DNase is required for normal progression of GAS infection, we generated seven isogenic mutant strains in which the three chromosomal- and prophage-encoded DNases made by a contemporary serotype M1 GAS strain were inactivated. Compared to the wild-type parental strain, the isogenic triple-mutant strain was significantly less virulent in two mouse models of invasive

SUBMITTER: Sumby P 

PROVIDER: S-EPMC547841 | biostudies-literature | 2005 Feb

REPOSITORIES: biostudies-literature