1. Bioinformatics and Molecular Design Research Center, Seoul 120-749, Korea, Graduate Program in Functional Genomics, Yonsei University, Seoul 120-749, Korea, Department of Bioinformatics and CAMD Research Center, Soongsil University, Seoul 156-743, Korea, Department of Biotechnology, Yonsei University, Seoul 120-749, Korea, and Department of Chemistry, Hannam University, 461-6 Jeonmin-Dong, Yuseong-Gu, Daejeon 305-811, Korea