Role of Chloroflexus-like bacteria in cycling of organic compounds in benthic microbial ecosystems

• Applicant: Dr. Dirk de Beer, since 9/2006
• Subject Area: Microbial Ecology and Applied Microbiology
• Term: from 2003 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5408870

Chloroflexus and affiliated filamentous anoxygenic phototrophic bacteria form, from both an ecological and evolutionary point of view, a very interesting group of prokaryotes. The group forms a distinct and ancient line of prokaryotes and laboratory studies with isolated strains revealed that individual species are metabolically extremely versatile, their present day distribution, however, appears to be limited. Moreover, current knowledge about their in situ metabolism and competitive capacities towards other bacteria is extremely limited. The clarification of their ecological niche through understanding of the physiology studied by direct techniques is the primary goal of this proposed research. State of the art in situ techniques, i.w. microsensor measurements, radiotracer incubations in combination with molecular techniques, will be applied to elucidate the ecological role ot these unique bacteria in the cycling of organic carbon compounds in recent microbial sediment ecosystems. Laboratory studies with specific enrichments and isolated strains are planned to explore the full physiological potential of representative members and, subsequently, in situ studies have to reveal whether the metabolic potential is fully or only partly employed and how this relates to environmental conditions and to the presence of competitors. This study will make a significant contribution to the elucidation of carbon-cycling in microbial sediment ecosystems.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Henk M. Jonkers, until 9/2006