Abstract

Borrelia burgdorferi sensu stricto is the predominant cause of Lyme disease. B. burgdorferi strains carry several linear and circular plasmids and this may be also used as a distinguishing property of the bacteria. The presence of a mixed population of linear and circular plasmids makes separation and characterization of each kind very difficult. In this study, 7 clinical strains of skin and CSF isolates were determined by clonal selection and plasmid profile of B. burgdorferi by electron microscopy and 2-dimensional agarose gel electrophoresis. The results demonstrate that the skin isolate (DK1) has 2 different phenotypes A and B, but the CSF isolate (DK6) has only 1 phenotype. Plasmid profiles from different strains of B. burgdorferi showed extreme complexity analyzed by conventional agarose electrophoresis. In conclusion, the DK1 strain has 10 plasmids in comparison to 6 plasmids in the DK6 strain. This could be due to a mixture of 2 phenotypes in the DK1 strain. Most of the plasmids in both strains were linear. This conclusion is supported by DNA hybridization, electron microscopy of plasmids, and amplification experiments with OspA-B specific primers. © TÜBİTAK.