Abstract
A chemically defined medium capable of eliciting high titers of skin permeability factor (PF)/enterotoxin from three different strains of Vibrio cholerae has been developed. Toxin/antigen elaboration in synthetic and in complex media was monitored by a specific passive hemagglutination-inhibition test. A distinct temporal difference in the pattern of toxin/antigen elaboration was noted when the two types of media were compared. In complex media, PF activity and corresponding antigen release were coincident, whereas in the defined medium a biphasic pattern resulting in elaboration of nontoxic antigen during the second phase was seen. Possible reasons for the latter observation are discussed, and several experiments illustrating the unique utility of the defined medium are presented.