Interspecific actions of alpha mating pheromones on the a mating-type cells of three Saccharomyces yeasts.

The alpha mating pheromones synthesized in three Saccharomyces yeasts (S. cerevisiae, S. kluyveri, and S. exiguus) displayed interspecific actions on the a cells of all three species despite the fact that the amino acid sequences of all three alpha pheromones are different. Mating between species, however, did not occur. The interspecific alpha pheromone--a cell reaction was not necessarily more effective than the interspecific one.