1. Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota Twin Cities, Minneapolis, MN 55455, USA
2. Department of Computer Science and Engineering, University of Minnesota Twin Cities, Minneapolis, MN 55455, USA
3. Department of Computer Science, University of Central Florida, Orlando, FL 32816, USA
4. Department of Microbiology and Molecular Genetics, University of California School of Medicine, Irvine, CA 92697, USA