[Specificity of the recombinant DNA pCX7 and its restriction enzyme map]

The recombinant DNA pCX7 derived from L. interrogans serovar lai strain 017 was applied for hybridization with 17 strains (8 serogroups of L. interrogans, L. biflexa strain Patoc I and Leptonema strain 3055); meanwhile 15 restriction endonucleases were used for analysis of the restriction enzyme map of pCX7. The result showed that the recombinant DNA probe is specific to species L. interrogans and its homology with DNA from different leptospires. A restriction enzyme map of pCX7 was constructed. Unique site for Bgl II and 3 sites for Bst BI were located within the cloned fragment (1.7 kb).