Phylogenetic identification of three strains of rhizosphere bacteria based on the results of 16s rRNA gene analysis and genetic typing

The rhizosphere nitrogen-fixing bacteria Herbaspirillum frisingense B416, Burkholderia sp. 418, and Herbaspirillum huttiense B601 (degrader of chlorinated s-triazines) were identified by phylogenetic analysis of the 16S rRNA gene sequences, characterization of the 16S-23S intergenic spacer region, Rep-PCR genotyping, and assessment of differentiating phenotypic characteristics. The results obtained indicate that, for correct taxonomic affiliation by comparative analysis of 16S rRNA gene sequences, the ratio between intra-and interspecies variability of these sequences within the group of bacteria closely related to the identified strain should be taken into consideration. If the interspecies differences between 16S rRNA genes are insufficient for differentiation of closely related species, ribotyping and Rep-PCR analysis of genomic DNA can be used for determination of the species affiliation.