1. Department of Biological Chemistry, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-chyo, Sakai, Osaka 599-8531, Japan, and Division of Bioscience and Biotechnology for Future Bioindustries, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi Aoba-ku, Sendai 981-8555, Japan