Ethanol inhibition of D-xylulose fermentation by Schizosaccharomyces pombe

Summary The kinetics of the utilization of D-xylulose by the yeast Schizosaccharomyces pombe has been examined under anaerobic batch conditions. The inhibitory effect of ethanol on xylulose uptake and ethanol production was studied at pH 6.0 and 30°C. Ethanol had little or no effect on the sugar uptake rate, but end product inhibition was observed on ethanol production. This non-competitive inhibition was linear with respect to ethanol concentration between 0 and 60 g/l. A kinetic model for the alcoholic fermentation of xylulose is presented.     

Radiation resistance in Schizosaccharomyces pombe

The fission yeast Schizosaccharomyces pombe serves as an excellent alternative and complementary model system for the analysis of genes and gene products involved in DNA repair. This brief review outlines the advantages of S. pombe and describes the radiation-sensitive mutants available for the analysis of DNA repair and recombination mechanisms in this organism. The progress in the cloning and characterization of representative genes is also described.     

Mutations induced by x-radiation in the yeast Schizosaccharomyces pombe

Experiments in strains of yeast with different genetic backgrounds were done to evaluate the kinetics of inactivation and mutation induction by X-radiations. A system of forward mutation induction in five loci was used and a specific mutation rate of 0.14·10⁻⁸×locus×rad was evaluated for the wild type.From a comparison of observations with wild type and radiation-sensitive strains, it may be assumed that, in this yeast, mutations are mainly the result of a repair-active process.The range of genotypic and phenotypic influence upon the specific locus mutation rate was evaluated with appropriate biological material and experiments.