1. Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
2. Department of Microbiology, Faculty of Public Health, Mahidol University, Bangkok, Thailand
3. Department of Oral Biology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
4. Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan