Cholera toxin genes: nucleotide sequence, deletion analysis and vaccine development.John J Mekalanos, Dr. Frank J. Swartz, Gail Denise Pearson, Nigel Harford, F Groyne, Marlieke A. de WildeNature1983Nucleotide sequence and deletion analysis have been used to identify the regulatory and coding sequences comprising the cholera toxin operon (ctx). Incorporation of defined in vitro-generated ctx… (More)