1. Research Center for Emerging Infectious Diseases, Research Institute for Microbial Diseases; Osaka University; Suita Osaka 565 Japan
2. Department of Bacterial Infections, Research Institute for Microbial Diseases; Osaka University; Suita Osaka 565 Japan
3. Quarantine Station of Osaka; Minato-ku; Osaka Osaka 552 Japan
4. Toyobo Research Center; Ohtsu Shiga 520-02 Japan