Emended description of the order Chlamydiales
, proposal of Parachlamydiaceae fam nov and Simkaniaceae fam nov, each containing one monotypic genus, revised taxonomy of the family Chlamydiaceae, including a new genus and five new species, and standards for the identification of organisms.
Wide range of Chlamydiales
types detected in native Australian mammals.
A PCR (4) to detect the 16S rRNA of all Chlamydiales bacteria, performed on liver tissue samples from all animals, yielded positive results in all 5 Corsican fire salamanders; in 4/7, 1/3, and 1/1 yellow spotted newts; and in 4/5 and 1/1 Strauch's spotted newts.
The novel Chlamydiales forms a distinct branch in the well-supported monophyletic clade with the genera Chlamydia and Candidatus Clavochlamydia salmonicola (family Chlamydiaceae) (Figure).
Despite the short sequence length of the 15 samples, the tree was well resolved with the Chlamydiales sequences and formed 3 clusters (Chlamydiaceae, Rhabdochlamydiaceae/Simkaniaceae, and Parachlamydiaceae/Waddliaceae/Criblamydiaceae) (Figure).
Molecular evidence for the existence of additional members of the order Chlamydiales.
Criblamydia sequanensis, a new intracellular Chlamydiales
isolated from Seine river water using amoebal co-culture.
Waddlia chondrophila, another Chlamydiales
, is a new abortigenic agent in bovines (5,6).
Since elementary and reticulate bodies are similar in both Chlamydiaceae and Parachlamydiaceae (6), Chlamydiales
cannot be identified in a specimen solely by electron microscopy.
For phylogenetic analyses, sequence data on complete 16S rRNA genes for each of the Chlamydiales
genera were retrieved from GenBank and aligned with ClustalW (24).
(3,5), Bradyrhizobiaceae (37), Rickettsiales (38), Listeria monocytogenes (39), M.
Arguments supporting a pathogenic role are that Chlamydia pneumoniae, a well-recognized agent of pneumonia, was shown to infect free-living amoebae and that another member of the Chlamydiales
, Simkania negevensis, which has 88% homology with Parachlamydia acanthamoebae, has caused pneumonia in adults and acute bronchiolitis in infants.