Institution: | Department of Environmental Chemistry and Microbiology, National Environmental Research Institute, P.O. Box 358, Roskilde 4000, Denmark;Section of Genetics and Microbiology, Department of Ecology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, Frederiksberg C 1871, Denmark;Section of Molecular Microbiology, BioCentrum, Technical University of Denmark, Lyngby 2800, Denmark |