Isolierung und genetische Charakterisierung von Stämmen des Planctomycetengenus Rhodopirellula und die Biogeographie in europäischen Gewässern

The isolation of new strains of the planctomycete genus Rhodopirellula and their genetic characterisation should provide new insights into the diversity and biogeography of an attached- living bacterium. Within this work 130 different samples of marine water, sediment, algae and plankton have been collected and examined by cultivation experiments. Out of 19 different samples 70 new strains close related to Rhodopirellula baltica were isolated. The majority of strains was gained from European Seas with Iceland as northernmost and Greece as southernmost site. Also strains from Tansania and the Philippines were obtained. All strains showed a high similarity to R. baltica by 16S rDNA sequences and further experiments approved these results. It was also possible to distinguish different groups of isolates by techniques like DNA-DNA-hybridization and MLSA. An electron microscopic study of selected strains showed the special intracytoplasmatic compartimentation, typical for Planctomycetes.