1. Research Group Environmental Microbiology and Molecular Ecology, Institute for Chemical Engineering, Vienna University of Technology, Gumpendorfer Straße 1a, A-1060 Vienna, Austria
2. Centre for Water Resource Systems (CWRS), Vienna University of Technology, Karlsplatz 13/222, A-1040 Vienna, Austria
3. Present address: Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, University of Vienna, Althanstraße 14, A-1090 Vienna, Austria
4. Department of Microbiology, Cornell University, Ithaca, NY 14853, USA
5. Gene Technology Group, Institute for Chemical Engineering, Vienna University of Technology, Gumpendorfer Straße 1a, A-1060 Vienna, Austria
6. Interuniversity Cooperation Centre Water & Health, Institute for Chemical Engineering, Vienna University of Technology, Gumpendorfer Straße 1a, A-1060 Vienna, Austria