1. Department of Bacteriology, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236, Osaka
2. Laboratory of Applied Microbiology, Suntory Limited Research Center, Shimamoto-Cho, Mishima-Gun, Osaka
3. Institute for Applied Life Science and Department of Enzymology, University of East Asia, 2-1 Ichinomiya-Gakuencho, Shimonoseki-Shi, Yamaguchi 751, Japan
4. Institut Pasteur, 28 rue du Docteur Roux, 75724 Paris Cédex 15, France