A PHYLOGENETIC ANALYSIS OF THE GENUS BLASTOBACTER WITH A VIEW TO ITS FUTURE RECLASSIFICATION

Near complete 16S rRNA gene sequences were determined for three cultur able species of the genus Blastobacter; B. aggregatus, B. capsulatus a nd B. natatorius and compared to the homologous sequences of Blastobac ter denitrificans and related members of the alpha subclass of the cla ss Proteobacteria. A phylogenetic analysis of the sequence data demons trated that B. aggregatus and B. capsulatus possessed high sequence si milarity to each other and to Agrobacterium tumefaciens (alpha-2 group of the alpha subclass), that B. natatorius was most closely related t o Caulobacter subvibrioides, Porphyrobacter neustonensis and Erythroba cter longus (alpha-4 group) and that B. denitrificans groups with Brad yrhizobium japonicum and Rhodopseudomonas palustris (alpha-2 group in a branch distinct from B. aggregatus and B. capsulatus). Thus the genu s Blastobacter is highly heterogeneous and its taxonomy should be revi sed.