Taxonomic heterogeneity within the Planctomycetales as derived by DNA-DNA hybridization, description of Rhodopirellula baltica gen. nov., sp nov., transfer of Pirellula marina to the genus Blastopirellula gen. nov as Blastopirellula marina comb. nov and emended description of the genus Pirellula

Ninety-seven strains of budding bacteria originating from various aquatic habitats and morphologically resembling planctomycetes were investigated taxonomically. Taxonomic differentiation was based on DNA-DNA hybridization, physiological properties and chemotaxonomic tests. Nineteen hybridization groups, containing 79 of the tested strains, were established. Eighteen strains, however, did not fit into any of these groups. Rhodopirellula baltica gen. nov., sp. nov. is described, with strain SH 1(T) ( = IFAM 1310(T) = DSM 10527(T) = NCIMB 13988(T)) as the type strain. Pirellula marina is transferred to the genus Blastopirellula gen. nov. as Blastopirellula marina comb. nov., with strain SH 106(T) ( = IFAM 1313(T) = DSM 3645(T) = ATCC 49069(T)) as the type strain. An emended description of the genus Pirellula is also provided. Differentiation between R. baltica, B. marina and Pirellula staleyi was achieved by the integration of morphological, physiological, chemotaxonomic and genetic characteristics.