Identification of Beijerinckia fluminensis strains CIP 106281T and UQM 1685T as Rhizobium radiobacter strains, and proposal of Beijerinckia doebereinerae sp nov to accommodate Beijerinckia fluminensis LMG 2819

During the course of a research project with free-living, nitrogen-fixing bacteria, we determined the 16S rRNA gene sequence of Beijerinckia fluminensis strains UQM 1685(T) and CIP 106281(T) and discovered that they were only 90.6-91.2% similar to the sequences of strains of other Beijerinckia species and subspecies. Moreover, the highest similarity to these sequences (99.7%) corresponded to strains of Rhizobium radiobacter (including Agrobacterium tumefaciens). Other diagnostic features confirmed that the two strains have the same origin but do not descend from the nomenclatural type. At the same time, B. fluminensis LMG 2819 was characterized and it was found that its properties also do not agree with the original description of the species, although it can be considered a member of the genus. Further characterization, including chemotaxonomic and other phenotypic traits, allows us to propose (i) the identification of B. fluminensis strains CIP 106281(T) and UQM 1685(T) as strains of Rhizobium radiobacter and (ii) the designation of strain LMG 2819(T) (= CECT 7311(T)) as the type strain of a novel species, Beijerinckia doebereinerae sp. nov.