1. Laboratory of Biochemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka 812-8581, Japan, Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan, RIKEN Harima Institute/SPring-8, 1-1-1 Koto, Mikazuki-cho, Sayo-gun, Hyogo 679-5148, Japan, and Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan