Several haploid species of Saccharomyces and Schiz. octosporus were shown to ferment sucrose in Durham tubes after a delay of 3 to 4 weeks. Detailed studies were done with a strain of S. rouxii. The delayed fermentation of sucrose was not caused by mutationselection or by inducible enzyme formation, since young glucose grown cells after drying, freezing, aging or autolysis contained an active sucrase. Cells pretreated by drying or freezing fermented sucrose nearly as fast as glucose. After autolysis, the sucrase of S. rouxii is only present in the cell debris and not in the autolysate. The use of a heavy inoculum in the van Iterson-Kluyver fermentometer resulted in a slow, but non-delayed fermentation. Variation in the pH or sucrose concentration had little effect on the delayed fermentation. It is suggested that after sufficient aging of the cells, the cell wall permeability undergoes a rather abrupt change, allowing the sucrose to come in contact with the sucrase of the cells.
ASJC Scopus subject areas
- Molecular Biology