Evaluation of genetic divergence of borrelial isolates from Lyme disease patients in Hokkaido, Japan, by rRNA gene probes.

Eight spirochetal isolates (JEM1 to JEM8) were obtained from cutaneous lesions of patients with Lyme disease in Hokkaido, Japan, and were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, reactivities with monoclonal and polyclonal antibodies, and Southern blot hybridization. The protein profiles of these borrelial isolates were variable and differed markedly from that of Borrelia burgdorferi B31. The 41-kDa flagellin protein was present in all isolates, but the outer surface protein A that reacted with monoclonal antibody H5332 was absent from four clinical isolates (JEM1, JEM5, JEM7, and JEM8). Genomic hybridization with rRNA gene probes demonstrated the genetic divergences among those isolates. These findings indicate that the borrelial isolates from patients in Japan are quite characteristically unique.