1. Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan, Chemical Genomics Research Group, RIKEN Advanced Science Institute, Wako, Saitama 351-0198, Japan, Biomedicinal Information Research Center, Japan Biological Informatics Consortium, 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan, and National Institute of Advanced Industrial Science and Technology, 2-4-7, Aomi, Koto-ku, Tokyo 135-0064, Japan