Massive genomic decay in Serratia symbiotica, a recently evolved symbiont of aphids.

ABSTRACT: All vertically transmitted bacterial symbionts undergo a process of genome reduction over time, resulting in tiny, gene-dense genomes. Comparison of genomes of ancient bacterial symbionts gives only limited information about the early stages in the transition from a free-living to symbiotic lifestyle because many changes become obscured over time. Here, we present the genome sequence for the recently evolved aphid symbiont Serratia symbiotica. The S. symbiotica genome exhibits several of the hallmarks of genome evolution observed in more ancient symbionts, including elevated rates of evolution and reduction in genome size. The genome also shows evidence for massive genomic decay compared with free-living relatives in the same genus of bacteria, including large deletions, many pseudogenes,

SUBMITTER: Burke GR 

PROVIDER: S-EPMC3056288 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature