Gene decay in Shigella as an incipient stage of host-adaptation.

ABSTRACT:

Background

Many facultative bacterial pathogens have undergone extensive gene decay processes, possibly due to lack of selection pressure during evolutionary conversion from free-living to intracellular lifestyle. Shigella, the causative agents of human shigellosis, have arisen from different E. coli-like ancestors independently by convergent paths. As these bacteria all have lost large numbers of genes by mutation or deletion, they can be used as ideal models for systematically studying the process of gene function loss in different bacteria living under similar selection pressures.

Methodologies/principal findings

We compared the sequenced Shigella genomes and re-defined decayed genes (pseudogenes plus deleted genes) in these bacteria. Altogether, 85 genes are commonly dec

SUBMITTER: Feng Y 

PROVIDER: S-EPMC3218036 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature