[Use of R plasmids for isolating Vibrio cholerae donor strains]

Vibrio cholerae and Vibrio eltor donor strains were obtained using R plasmids RP1ts, pRP19.6, pTH10 and pNS10 which carry IS or Tn elements. Resulting from integration of the plasmids into cholera vibrio chromosome, two types of donors were constructed: those resembling Escherichia coli Hfr's and the strains analogous to F+ or F' donors. The order of some chromosome markers were determined in crosses between the donors obtained and V. cholerae recipient strains.