1. Center of Future Nanomaterials, Institute of Symbiotic Sciences and Technology, Tokyo University of Agriculture and Technology, 2-24-16, Nakamachi, Koganei 184-8588, Japan, Graduate School of Bioscience and Bioengineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan, and Department of Materials Science, Ibaraki University, Nakanarusawa 4-12-1, Hitachi, Ibaraki 316-8511, Japan tyamazak@cc.tuat.ac.jp