Expression of Antigen Genes of Leptospira interrogans Serovar canicola in Escherichia coli

Leptospira interrogans serovar canicola DNA was cloned into the plasmid pBR322 and introduced into E. coli. Eight out of approximately 10,000 transformants were found to express antigens of canicola by ELISA including colony ELISA blot test using anti-canicola antiserum. The canicola antigens expressed in the transformants reacted with the antisera against the serovars belonging to Canicola serogroup and other serogroups of L. interrogans. They did not react, however, with the antiserum against L. biflexa (with only one exception) nor with the antiserum against Leptonema illini. Thus, the recombinant DNA technique may provide alternative possibilities for preparing antigens of leptospires.