1. Life Science Laboratory, Shimadzu Corporation, Kyoto 604-8511, Japan, Department of Chemistry, Nara Women's University, Nara 630-8506, Japan, Institute for Protein Research and Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan, and Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan