1. Department of Microbiology, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea.
2. Department of Microbiology, Molecular Biology and Biochemistry, University of Idaho, Moscow, Idaho 83844, USA.
3. Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.
4. Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA.
5. Animal Health Research, LG Life Sciences Ltd., Daejeon 305-380, Korea.