DELETION MUTANT AS VACCINE FOR CHOLERA

摘要

PROBLEM TO BE SOLVED: To provide nontoxigenic, genetically stable mutant strains of Vibrio cholerae, and to provide a method for producing mutant strains which are useful as live, oral vaccines for inducing immunological protection against cholera. SOLUTION: The mutant strains are genetically engineered mutants which lack DNA encoding a functional ctxA subunit which is responsible for many of the symptoms of cholera. The strains also lack any functional attRS1 sequences which are required for recombination and amplification of the CTX genetic element. These strains are safe because they can not recombine with the wild type attRS1-containing vehicles which include the ctxA-encoding DNA. COPYRIGHT: (C)2004,JPO