Evolutionary paths of streptococcal and staphylococcal superantigens.

ABSTRACT:

Background

Streptococcus pyogenes (GAS) harbors several superantigens (SAgs) in the prophage region of its genome, although speG and smez are not located in this region. The diversity of SAgs is thought to arise during horizontal transfer, but their evolutionary pathways have not yet been determined. We recently completed sequencing the entire genome of S. dysgalactiae subsp. equisimilis (SDSE), the closest relative of GAS. Although speG is the only SAg gene of SDSE, speG was present in only 50% of clinical SDSE strains and smez in none. In this study, we analyzed the evolutionary paths of streptococcal and staphylococcal SAgs.

Results

We compared the sequences of the 12-60 kb speG regions of nine SDSE strains, five speG(+) and four speG(-). We found that the synteny of this

SUBMITTER: Okumura K 

PROVIDER: S-EPMC3538662 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature