title: Small genome of Candidatus Blochmannia, the bacterial endosymbiont of Camponotus, implies irreversible specialization to an intracellular lifestyle.
abstract: Blochmannia (Candidatus Blochmannia gen. nov.) is the primary bacterial endosymbiont of the ant genus CAMPONOTUS: Like other obligate endosymbionts of insects, Blochmannia occurs exclusively within eukaryotic cells and has experienced long-term vertical transmission through host lineages. In this study, PFGE was used to estimate the genome size of Blochmannia as approximately 800 kb, which is significantly smaller than its free-living relatives in the enterobacteria. This small genome implies that Blochmannia has deleted most of the genetic machinery of related free-living bacteria. Due to restricted gene exchange in obligate endosymbionts, the substantial gene loss in Blochmannia and other insect mutualists may reflect irreversible specialization to a host cellular environment.
authors.affiliation: Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543, USA1.
authors.forename: J J
authors.initials: JJ
authors.lastname: Wernegreen
authors.affiliation: Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543, USA1.
authors.forename: Adam B
authors.initials: AB
authors.lastname: Lazarus
authors.affiliation: Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543, USA1.
authors.forename: Patrick H
authors.initials: PH
authors.lastname: Degnan
mesh_terms: D000818:Animals; D001000:Ants / Q000145:classification / Q000201:enzymology / Q000382:microbiology*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D020563:Gammaproteobacteria / Q000235:genetics* / Q000302:isolation & purification; D040961:Genetic Drift; D016680:Genome, Bacterial; D008969:Molecular Sequence Data; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013559:Symbiosis
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S