Bordetella petrii sp. nov., isolated from an anaerobic bioreactor, and emended description of the genus Bordetella.

A novel Bordetella species was isolated from an anaerobic, dechlorinating bioreactor culture enriched from river sediment. The only strain, Se-1111R(T) (= DSM 12804T = CCUG 43448T), for which the name Bordetella petrii is proposed, is designated the type strain of the novel species. Strain Se-1111R(T) was isolated from the dechlorinating mixed culture due to its ability to anaerobically reduce selenate to elemental selenium. Comparative 16S rDNA sequence analysis showed a close relationship between Se-1111R(T) and members of the genus Bordetella within the beta-Proteobacteria. This close phylogenetic relatedness was also reflected in several metabolic properties of Se-1111R(T), including its incapacity to utilize carbohydrates, by the high G+C content (63.8 mol%) of its DNA and by the presence of Q-8 as the major isoprenoid quinone. DNA-DNA hybridization experiments with type strains of all species of the genus Bordetella and closely related species Achromobacter xylosoxidans subsp. denitrificans provided further evidence for the assignment of strain Se-1111R(T) as a novel species of the genus Bordetella. This genus currently consists of seven aerobic species, all of which are known to occur in close pathogenic, opportunistic or possibly commensal relationships with various host organisms. B. petrii is the first member of this genus isolated from the environment and capable of anaerobic growth. The proposal of the novel species and an emended description of the genus Bordetella is presented.