1. Department of Applied Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
2. Department of Pharmacy, College of Pharmaceutical Sciences, Ritsumeikan University, Nojihigashi, Kusatsu, Shiga 525-8577, Japan
3. Institute for Protein Research, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan
4. Institute of Microbial Chemistry, Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan