The rpoS gene is predominantly inactivated during laboratory storage and undergoes source-sink evolution in Escherichia coli species.

ABSTRACT: The rpoS gene codes for an alternative RNA polymerase sigma factor, which acts as a general regulator of the stress response. Inactivating alleles of rpoS in collections of natural Escherichia coli isolates have been observed at very variable frequencies, from less than 1% to more than 70% of strains. rpoS is easily inactivated in nutrient-deprived environments such as stab storage, which makes it difficult to determine the true frequency of rpoS inactivation in nature. We studied the evolutionary history of rpoS and compared it to the phylogenetic history of bacteria in two collections of 82 human commensal and extraintestinal E. coli strains. These strains were representative of the phylogenetic diversity of the species and differed only by their storage conditions. In both collections,

SUBMITTER: Bleibtreu A 

PROVIDER: S-EPMC4248845 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature