Kinetics of the mating-specific aggregation in Saccharomyces cerevisiae.

Procedures are described for obtaining efficient mating (zygote formation) in the heterothallic yeast Saccharomyces cerevisiae. The methods separate operationally the initial, mating-specific aggregation from subsequent steps in conjugation. This cell-cell interaction has been characterized. The data support the conclusions that (i) aggregation in liquid suspension is a random collision process, and (ii) only non-budded cells participate in aggregation. A mathematical model for the kinetics of aggregation in liquid suspension has been developed which is in good agreement with the experimental data.