1. Division of Microbiology, Department of Infectious Diseases, Faculty of Medicine, University of Miyazaki, 5200 Kiyotake, Miyazaki 889-1692, Japan
2. Division of Bioenvironmental Science, Frontier Science Research Center, University of Miyazaki, 5200 Kiyotake, Miyazaki 889-1692, Japan
3. Laboratory of Genomic Research on Pathogenic Bacteria, International Research Center for Infectious Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
4. Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
5. National Reference Laboratory for Escherichia coli, Department of Biological Safety, Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, D-12277 Berlin, Germany