Inclusion Membrane Proteins of Protochlamydia amoebophila UWE25 Reveal a Conserved Mechanism for Host Cell Interaction among the Chlamydiae

Eva Heinz, Daniel D. Rockey, Jacqueline Montanaro-Punzengruber, Karin Aistleitner, Michael Wagner, Matthias Horn (Korresp. Autor*in)

    Veröffentlichungen: Beitrag in FachzeitschriftArtikelPeer Reviewed


    Chlamydiae are a group of obligate intracellular bacteria comprising several important human pathogens. Inside the eukaryotic cell, chlamydiae remain within a host-derived vesicular compartment, termed the inclusion. They modify the inclusion membrane through insertion of unique proteins, which are involved in interaction with and manipulation of the host cell. Among chlamydiae, inclusion membrane proteins have been exclusively found in members of the family Chlamydiaceae, which predominantly infect mammalian and avian hosts. Here, the presence of inclusion membrane proteins in Protochlamydia amoebophila UWE25, a chlamydial endosymbiont of free-living amoebae, is reported. A genome-wide screening for secondary structure motifs resulted in the identification of 23 putative inclusion membrane proteins for this organism. Immunofluorescence analysis demonstrated that five of these proteins were expressed, and four of them could be localized to a halo surrounding the intracellular bacteria. Colocalization studies showed an almost complete overlap of the signals obtained for the four putative inclusion membrane proteins, and immuno-transmission electron microscopy unambiguously demonstrated their location in the inclusion membrane. The presence of inclusion membrane proteins (designated IncA, IncQ, IncR, and IncS) in P. amoebophila shows that this strategy for host cell interaction is conserved among the chlamydiae and is used by chlamydial symbionts and pathogens alike.
    Seiten (von - bis)5093-5102
    FachzeitschriftJournal of Bacteriology
    PublikationsstatusVeröffentlicht - 2010

    ÖFOS 2012

    • 106022 Mikrobiologie