title: Missing links in the divergence of Chlamydophila abortus from Chlamydophila psittaci.
abstract: Pathological and serological evidence and DNA-DNA reassociation data indicate that Chlamydophila psittaci and Chlamydophila abortus are separate species. C. psittaci causes avian systemic disease and C. abortus causes abortion. Both previously belonged to Chlamydia psittaci are associated with zoonotic and enzootic outbreaks. Genetic studies suggest that they are closely related and because of the recent availability of diverse C. psittaci strains and comparative data for several genes, it was possible to explore this relationship. The parrot C. psittaci strain 84/2334 was found to have DNA sequences that were identical to an extrachromosomal plasmid in duck C. psittaci strain N352, to rnpB in strain R54 from a brown skua and to the rrn intergenic spacer in parakeet strain Prk/Daruma (from Germany, Antarctica and Japan, respectively). Analysis of ompA and the rrn spacer revealed progressive diversification of the strains, with 84/2334 resembling what might have been a recent ancestor of C. abortus. Another C. psittaci strain (VS225) showed evidence of having undergone convergent evolution towards the C. abortus-like genotype, whereas strain R54 diverged independently. For the first time, these studies link C. abortus in an evolutionary context to the C. psittaci lineage. It has been concluded that C. abortus diverged from C. psittaci, and so strain R54 was designated a C. psittaci strain. It is recommended that characterization of C. psittaci and C. abortus strains should utilize more than a single method and more than a single gene.
authors.affiliation: Department of Animal Sciences, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21 (Laboratory of Gene Technology) and 30 (Laboratory of Physiology and Immunology of Domestic Animals), 3001 Leuven, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Van Loock
authors.affiliation: Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Vanrompay
authors.affiliation: Department of Clinical Microbiology, University Hospital, S-751 85 Uppsala, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Herrmann
authors.affiliation: Department of Animal Sciences, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21 (Laboratory of Gene Technology) and 30 (Laboratory of Physiology and Immunology of Domestic Animals), 3001 Leuven, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Vander Stappen
authors.affiliation: Department of Animal Sciences, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21 (Laboratory of Gene Technology) and 30 (Laboratory of Physiology and Immunology of Domestic Animals), 3001 Leuven, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Volckaert
authors.affiliation: Department of Animal Sciences, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21 (Laboratory of Gene Technology) and 30 (Laboratory of Physiology and Immunology of Domestic Animals), 3001 Leuven, Belgium.
authors.forename: B M
authors.initials: BM
authors.lastname: Goddeeris
authors.affiliation: Department of Microbiology, University of Georgia, Athens, GA 30602, USA.
authors.forename: K D E
authors.initials: KDE
authors.lastname: Everett
mesh_terms: D000034:Abortion, Veterinary / Q000382:microbiology*; D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001483:Base Sequence; D001715:Bird Diseases / Q000382:microbiology* / Q000503:physiopathology; D023501:Chlamydophila / Q000235:genetics* / Q000472:pathogenicity; D023521:Chlamydophila Infections / Q000382:microbiology / Q000503:physiopathology / Q000662:veterinary*; D002691:Chlamydophila psittaci / Q000235:genetics* / Q000472:pathogenicity; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D004722:Endoribonucleases / Q000235:genetics; D019143:Evolution, Molecular; D005260:Female; D006168:Guinea Pigs; D051379:Mice; D008969:Molecular Sequence Data; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics; D011247:Pregnancy; D016337:RNA, Catalytic / Q000235:genetics; D011817:Rabbits; D043262:Ribonuclease P; D017422:Sequence Analysis, DNA; D012756:Sheep; D012757:Sheep Diseases / Q000382:microbiology* / Q000503:physiopathology
chemical_list: D001425:Bacterial Outer Membrane Proteins; D021903:DNA, Ribosomal Spacer; D016337:RNA, Catalytic; C078167:OMPA outer membrane proteins; D004722:Endoribonucleases; D043262:Ribonuclease P