Pilus operon evolution in Streptococcus pneumoniae is driven by positive selection and recombination.

ABSTRACT:

Background

The evolution of bacterial organelles involved in host-pathogen interactions is subject to intense and competing selective pressures due to the need to maintain function while escaping the host immune response. To characterize the interplay of these forces in an important pathogen, we sequenced the rlrA islet, a chromosomal region encoding for a pilus-like structure involved in adherence to lung epithelial cells in vitro and in colonization in a murine model of infection, in 44 clinical isolates of Streptococcus pneumoniae.

Results

We found that the rrgA and rrgB genes, encoding the main structural components of the pilus, are under the action of positive selection. In contrast, the rrgC gene, coding for a component present in low quantities in the assembled pilus

SUBMITTER: Muzzi A 

PROVIDER: S-EPMC2576445 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature