title: Bacterial endosymbionts in animals.
abstract: Molecular phylogenetic studies reveal that many endosymbioses between bacteria and invertebrate hosts result from ancient infections followed by strict vertical transmission within host lineages. Endosymbionts display a distinctive constellation of genetic properties including AT-biased base composition, accelerated sequence evolution, and, at least sometimes, small genome size; these features suggest increased genetic drift. Molecular genetic characterization also has revealed adaptive, host-beneficial traits such as amplification of genes underlying nutrient provision.
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, 85721, USA. nmoran@u.arizona.edu
authors.forename: N A
authors.initials: NA
authors.lastname: Moran
authors.forename: P
authors.initials: P
authors.lastname: Baumann
mesh_terms: D000818:Animals; D001419:Bacteria / Q000235:genetics* / Q000378:metabolism; D005075:Biological Evolution; D010957:Plasmids / Q000502:physiology; D013559:Symbiosis / Q000502:physiology*