IDENTIFICATION OF A PROTEIN IN SEVERAL BORRELIA SPECIES WHICH IS RELATED TO OSPC OF THE LYME-DISEASE SPIROCHETES

Using oligonucleotide probes which have previously been shown to be sp ecific for the ospC gene found in the Lyme disease spirochete species Borrelia burgdorferi, B. garinii, and group VS461, we detected an ospC homolog in other Borrelia species including B. coriaceae, B. hermsii, B. anserina, B. turicatae, and B. parkeri. In contrast to the Lyme di sease spirochetes, which carry the ospC gene on a 26-kb circular plasm id, we mapped the gene in other Borrelia species to linear plasmids wh ich varied in size among the isolates tested. Some isolates carry mult iple copies of the gene residing on linear plasmids of different sizes . The analyses conducted here also demonstrate that these Borrelia spe cies contain a linear chromosome. Northern (RNA) blot analyses demonst rated that the gene is transcriptionally expressed in all species exam ined. High levels of transcriptional expression were observed in some B. hermsii isolates. Transcriptional start site analyses revealed that the length of the untranslated leader sequence was identical to that observed in the Lyme disease spirochete species. By Western blotting ( immunoblotting) with antiserum (polyclonal) raised against the OspC pr otein of B. burgdorferi, we detected an immunoreactive protein of the same molecular weight as the OspC found in Lyme disease spirochete spe cies. The results presented here demonstrate the presence of a protein that is genetically and antigenically related to OspC which is expres sed in all species of the genus Borrelia tested.