Chitinase and chitin synthase 1: counterbalancing activities in cell separation of Saccharomyces cerevisiae

J Gen Microbiol. 1992 Jan;138(1):97-102. doi: 10.1099/00221287-138-1-97.


Previous results [E. Cabib, A. Sburlati, B. Bowers & S. J. Silverman (1989) Journal of Cell Biology 108, 1665-1672] strongly suggested that the lysis observed in daughter cells of Saccharomyces cerevisiae defective in chitin synthase 1 (Chs1) was caused by a chitinase that partially degrades the chitin septum in the process of cell separation. Consequently, it was proposed that in wild-type cells, Chs1 acts as a repair enzyme by replenishing chitin during cytokinesis. The chitinase requirement for lysis has been confirmed in two different ways: (a) demethylallosamidin, a more powerful chitinase inhibitor than the previously used allosamidin, is also a much better protector against lysis and (b) disruption of the chitinase gene in chs1 cells eliminates lysis. Reintroduction of a normal chitinase gene, by transformation of those cells with a suitable plasmid, restores lysis. The percentage of lysed cells in strains lacking Chs1 was not increased by elevating the chitinase level with high-copy-number plasmids carrying the hydrolase gene. Furthermore, the degree of lysis varied in different chs1 strains; lysis was abolished in chs1 mutants containing the scs1 suppressor. These results indicate that, in addition to chitinase, lysis requires other gene products that may become limiting.

MeSH terms

  • Cell Division
  • Chitin Synthase / genetics
  • Chitin Synthase / metabolism*
  • Chitinases / antagonists & inhibitors
  • Chitinases / genetics
  • Chitinases / metabolism*
  • Genes, Fungal
  • Genes, Suppressor
  • Mutation
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics


  • Chitin Synthase
  • Chitinases