Simkaniaceae

Simkaniaceae is a family of bacteria in the order Chlamydiales, class Chlamydiae, phylum Chlamydiae, domain Bacteria. Species in this family have a chlamydia-like cycle of replication and their ribosomal RNA genes are 80–90% identical to ribosomal genes in the Chlamydiaceae. The Simkaniaceae are not recognized by monoclonal antibodies that are specific for Chlamydiaceae lipopolysaccharide. The family Simkaniaceae currently includes two genera: Simkania and Fritschea. The type species is Simkania negevensis, and its natural host is not known. It is readily grown in monolayers of eukaryotic Vero cells. Serological evidence and PCR indicate that S. negevensis is widespread among humans.

Two Fritschea species have been identified in insects. These are candidatus species because they only grow in insect bacteriocytes and have not been cultured in vitro. Whiteflies are the host of Candidatus Fritschea bemisiae (strain Falk). Scale insects are the host of Candidatus Fritschea eriococci (strain Elm).

Simkania negevensis and Fritschea bemisiae have a group I intron in the 23S rRNA, unlike other characterized chlamydial rRNA genes. The introns are closely related to group I introns in the 23S rRNA of chloroplasts and mitochondria in algae and amoebae.

Notes

Notes:
♠ Strain found at the National Center for Biotechnology Information (NCBI) but has no standing with the Bacteriological Code (1990 and subsequent Revision) as detailed by List of Prokaryotic names with Standing in Nomenclature (LPSN) as a result of the following reasons:
• No pure culture isolated or available for Prokayotes.
• Not validly published because the effective publication only documents deposit of the type strain in a single recognized culture collection.
• Not approved and published by the International Journal of Systematic Bacteriology or the International Journal of Systematic and Evolutionary Microbiology (IJSB/IJSEM).

References