Emergence of a bacterial clone with enhanced virulence by acquisition of a phage encoding a secreted phospholipase A2.

ABSTRACT: The molecular basis of pathogen clone emergence is relatively poorly understood. Acquisition of a bacteriophage encoding a previously unknown secreted phospholipase A(2) (designated SlaA) has been implicated in the rapid emergence in the mid-1980s of a new hypervirulent clone of serotype M3 group A Streptococcus. Although several lines of circumstantial evidence suggest that SlaA is a virulence factor, this issue has not been addressed experimentally. We found that an isogenic DeltaslaA mutant strain was significantly impaired in ability to adhere to and kill human epithelial cells compared with the wild-type parental strain. The mutant strain was less virulent for mice than the wild-type strain, and immunization with purified SlaA significantly protected mice from invasive disease. Import

SUBMITTER: Sitkiewicz I 

PROVIDER: S-EPMC1635118 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature