1. Institute of Microbiology; University of Greifswald; Greifswald Germany
2. Department of Limnology and Oceanography; University of Vienna; Vienna Austria
3. Department of Health Sciences and Technology; ETH Zürich; Zürich Switzerland
4. Stream Biofilm and Ecosystem Research Laboratory; Ecole Polytechnique Fédérale de Lausanne (EPFL); ENAC Lausanne Switzerland