1. Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455
2. Center for Environmental Kinetics Analysis, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802
3. Department of Microbiology, University of Minnesota, Minneapolis, Minnesota 55455
4. BioTechnology Institute, University of Minnesota, St. Paul, Minnesota 55108