[1] Univ Tokyo, Grad Sch Sci, Dept Biochem & Biophys, Bunkyo Ku, Tokyo 113, Japan
[2] RIKEN, Inst Phys & Chem Res, Wako, Saitama 35101, Japan
[3] Matsushita Elect Ind Co Ltd, Int Inst Adv Res, Cent Res Labs, Kyoto 61902, Japan
[4] Ochanomizu Univ, Fac Sci, Dept Chem, Bunkyo Ku, Tokyo 112, Japan
[5] Scripps Res Inst, Skaggs Inst Chem Biol, La Jolla, CA 92037 USA