Abstract

Seven strains of the lyme disease agent, Borrelia burgdorferi isolated from skin and cerebrospinal fluid of patients with erythema migraines and acrodermatitis chronica atrophicans were examined for presence of linear and circular plasmids. By using two dimensional gel electrophoreses several linear and circular plasmid were identified, each strains contains 5 to 11 plasmid mostly linear, varying in size between 3 to 60 kb pairs, none of the strains has similar plasmid profile. Comparing plasmid profile of Danish isolates with plasmid profile of B. borgdurferi from different geographical area revealed similarity to Swedish isolates. After 42 passage of DK1 strain in BSK-II medium it has lost one 5.5 kb linear plasmid. PCR amplification of total plasmid from seven DK strains with primers designed from conserved region of OspA gene produced fragment with 822 bp similar to size of the primers span in published sequence. Cloning and sequencing of OspA gene from DK1 and DK6 strains has shown similarity between 75 to 95 to different B. burgdorferi. Electron Microscopy analysis of 25 kb plasmid revealed that this plasmid indeed has linear structure. DNA sequence of some fragments of 25 kb linear plasmid has shown similar sequence to eukaryotic viruses specially Vaccinia and Varriola. © 2006 Asian Network for Scientific Information.