1. Laboratory of Marine Microbiology, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University,
Kyoto 606‐8502, Japan
2. Laboratory of Food Hygiene, Faculty of Fisheries, Nagasaki University, Bunkyo‐machi, Nagasaki 852‐8521, Japan
3. Department of Marine Biotechnology, Faculty of Engineering, Fukuyama University, Fukuyama, Hiroshima 729‐0292, Japan