1. Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
2. Central Laboratory of Yamazaki Baking Company Limited, 3-23-27 Ichikawa, Ichikawa City, Chiba 272-8581, Japan