title: The evolution of chronic infection strategies in the alpha-proteobacteria.
abstract: Many of the alpha-proteobacteria establish long-term, often chronic, interactions with higher eukaryotes. These interactions range from pericellular colonization through facultative intracellular multiplication to obligate intracellular lifestyles. A common feature in this wide range of interactions is modulation of host-cell proliferation, which sometimes leads to the formation of tumour-like structures in which the bacteria can grow. Comparative genome analyses reveal genome reduction by gene loss in the intracellular alpha-proteobacterial lineages, and genome expansion by gene duplication and horizontal gene transfer in the free-living species. In this review, we discuss alpha-proteobacterial genome evolution and highlight strategies and mechanisms used by these bacteria to infect and multiply in eukaryotic cells.
authors.affiliation: Laboratory of Plant Microbe Interactions, CNRS-INRA, BP27, 31326 Castanet-Tolosan Cedex, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Batut
authors.forename: Siv G E
authors.initials: SG
authors.lastname: Andersson
authors.forename: David
authors.initials: D
authors.lastname: O'Callaghan
mesh_terms: D020561:Alphaproteobacteria / Q000472:pathogenicity* / Q000502:physiology*; D000818:Animals; D005075:Biological Evolution; D002908:Chronic Disease; D005057:Eukaryotic Cells / Q000382:microbiology; D016680:Genome, Bacterial; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology; D006801:Humans; D010944:Plants / Q000382:microbiology; D013559:Symbiosis; D014774:Virulence