Parallel genomic evolution and metabolic interdependence in an ancient symbiosis

Proc Natl Acad Sci U S A. 2007 Dec 4;104(49):19392-7. doi: 10.1073/pnas.0708855104. Epub 2007 Nov 28.

Abstract

Obligate symbioses with nutrient-provisioning bacteria have originated often during animal evolution and have been key to the ecological diversification of many invertebrate groups. To date, genome sequences of insect nutritional symbionts have been restricted to a related cluster within Gammaproteobacteria and have revealed distinctive features, including extreme reduction, rapid evolution, and biased nucleotide composition. Using recently developed sequencing technologies, we show that Sulcia muelleri, a member of the Bacteroidetes, underwent similar genomic changes during coevolution with its sap-feeding insect host (sharpshooters) and the coresident symbiont Baumannia cicadellinicola (Gammaproteobacteria). At 245 kilobases, Sulcia's genome is approximately one tenth of the smallest known Bacteroidetes genome and among the smallest for any cellular organism. Analysis of the coding capacities of Sulcia and Baumannia reveals striking complementarity in metabolic capabilities.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Bacteroidetes / classification
  • Bacteroidetes / genetics
  • Bacteroidetes / metabolism*
  • Base Sequence
  • Evolution, Molecular*
  • Genome, Bacterial*
  • Hemiptera / microbiology*
  • Molecular Sequence Data
  • Phylogeny
  • Symbiosis / genetics*

Associated data

  • GENBANK/CP000770