Pneumolysin with low hemolytic activity confers an early growth advantage to Streptococcus pneumoniae in the blood.

ABSTRACT: Streptococcus pneumoniae is a leading cause of human diseases such as pneumonia, bacteremia, meningitis, and otitis media. Pneumolysin (Ply) is an important virulence factor of S. pneumoniae and a promising future vaccine target. However, the expansion of clones carrying ply alleles with reduced hemolytic activity has been observed in serotypes associated with outbreaks of invasive disease and includes an allele identified in a highly virulent serotype 1 isolate (ply4496). The virulence of Ply-deficient and ply allelic-replacement derivatives of S. pneumoniae D39 was compared with that of wild-type D39. In addition, the protective immunogenicity of Ply against pneumococci with low versus high hemolytic activity was also investigated. Replacement of D39 ply with ply4496 resulted in a small

SUBMITTER: Harvey RM 

PROVIDER: S-EPMC3187248 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature