Patent ID: 8039008

Claim:
A recombinant Vibrio cholerae comprising a mutated transcriptional regulatory protein (ToxT) amino acid sequence, wherein the mutated ToxT comprises a mutation at a lysine corresponding to K203 of SEQ ID NO: 2 or a lysine corresponding to K237 of SEQ ID NO: 2, and wherein the mutation results in a reduction in the expression of cholera toxin by the recombinant Vibrio cholerae to less than 1% of the expression of cholera toxin from a Vibrio cholerae comprising a wild-type ToxT having the amino acid sequence of SEQ ID NO: 2, and an expression of toxin co-regulated pilus by the recombinant Vibrio cholerae that is at least 10% of the expression of toxin co-regulated pilus from a Vibrio cholerae comprising a wild-type ToxT having the amino acid sequence of SEQ ID NO: 2.