[The isolation of Vibrio cholerae strains that produce cholera toxin and its B-subunit]

The creation of two V. cholerae strains, belonging to the classical biovar, serovars Ogawa and Inaba, and serving as hyperproducers of cholera toxin, is described. The strains have been created by means of recombinant plasmid pCO107-2, carrying the cloned gene of cholera toxin vctAB. The use of recombinant plasmid pIEMZ3 carrying the cloned gene of the B-subunit of cholera toxin vctB has made it possible to obtain a strain, capable of producing the B-subunit of cholera toxin, on the basis of V. cholerae strain non 01. Besides, V. cholerae isogenic toxigenic strains, serovars Inaba and Ogawa, with the increased production of the B-subunit of cholera toxin, have been obtained.