title: Blurred pictures from the crime scene: the growing case for a function of Chlamydiales in plastid endosymbiosis.
abstract: A number of recent papers have brought suggestive evidence for an active role of Chlamydiales in the establishment of the plastid. Chlamydiales define a very ancient group of obligate intracellular bacterial pathogens that multiply in vesicles within eukaryotic phagotrophic host cells such as animals, amoebae or other protists, possibly including the hypothetical phagotroph that internalized the cyanobacterial ancestor of the plastid over a billion years ago. We briefly survey the case for an active role of these ancient pathogens in plastid endosymbiosis. We argue that a good understanding of the Chlamydiales infection cycle and diversity may help to shed light on the process of metabolic integration of the evolving plastid.
authors.affiliation: Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, F 59 000 Lille, France. Electronic address: steven.ball@univ-lille1.fr.
authors.forename: Steven G
authors.initials: SG
authors.lastname: Ball
authors.affiliation: Center for Research on Intracellular Bacteria (CRIB), Institute of Microbiology, University Hospital Center and University of Lausanne, 1011 Lausanne, Switzerland.
authors.forename: Gilbert
authors.initials: G
authors.lastname: Greub
mesh_terms: D005075:Biological Evolution; D002695:Chlamydiales / Q000235:genetics / Q000502:physiology*; D010944:Plants / Q000382:microbiology*; D018087:Plastids / Q000382:microbiology*; D013559:Symbiosis / Q000502:physiology*
keywords: Chlamydiales; Endosymbiosis; Glycogen; Ménage à trois hypothesis; Plastid