Interaction effects between flocculent and non-flocculent cells of S. cerevisiae

Abstract

Interaction between nonflocculent and flocculent cells of Saccharomyces cerevisiae was studied. Adhesion experiments were done using three types of nonflocculent cells and a flocculent one. Two types of nonflocculent cells were obtained from the flocculent strain by changing environmental growth conditions. The integration of nonflocculent cells in the flocs was observed by two different methods: measurement of the sedimentation capacity of mixtures and microscopic observation of stained nonflocculent cells blended with flocculent cells. It was possible to verify that cellcell interaction corresponds to a true stable binding and not to a simple entrapment inside the floe matrix. Key words: yeast, Saccharomyces cerevisiae, flocculation, adhesion.