1. Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
2. Department of Chemistry, University of Zürich, 8057 Zürich, Switzerland
3. Institute of Microbiology, CHUV, 1011 Lausanne, Switzerland
4. Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
5. MTA-BME Water Research Group, 1111 Budapest, Hungary