Synthesis and assembly of wall polymers on regenerating yeast protoplasts

Accumulation of chitin and glucan on S. cerevisiae and C. albicans protoplasts begins shortly after resuspension in the regeneration medium, and mannoprotein molecules also appear retained by the regenerating wall after 30-60 minutes in S. cerevisiae or after a longer lag period in C. albicans. Nevertheless, a considerable fraction of the synthesized mannoproteins, which in SDS-acrylamide gels exhibit a different pattern from that of wall manno-proteins of cells, are still released to the growth medium during at least eight hours. De novo synthesis of chitin synthase, but not of glucan synthase, is observed in S. cerevisiae from about 30 minutes after initiation of the regeneration process. The interaction between microfibrils of nascent chitin formed by C. albicans protoplasts is altered by strains as Calcofluor White or Congo Red. In the presence of the former one, no microcrystalline lattice of the polymer is formed and protoplasts do not regenerate correctly.