1. Department of Microbiology; Faculty of Pharmaceutical Sciences; Tohoku Medical and Pharmaceutical University; 4-4-1 Komatsushima Aoba-ku Sendai Miyagi 981-8558 Japan
2. Laboratory of Molecular and Biochemical Toxicology; Graduate School of Pharmaceutical Sciences; Tohoku University; Aoba-ku Sendai Miyagi 980-8578 Japan
3. Department of Microbiology and Cell Biology; Tokyo Metropolitan Institute of Medical Science; Kamikitazawa Setagaya-ku Tokyo 156-8506 Japan