| Under the condition of high pressure, the irritative reactionoccurred after being stimulated for the Yeast cells. At first,byusing Saccharomyces cerevias as initial strain, The factorsaffecting the cell penetrability including diferent pressurevalue,Their morphoiogical,physiological andfermentation pro-lies were studied.We determined Saccharomyces cerevias as reactiontemperature, pH value,flocculability capability,fermentationdegree,fermentation rate,alcohol tolerance and yield of diacetyland other parameters respectively. In this paper, we analyzed thechange mechanism of Saccharomyces cerevias under high pressure andelementarily probed changes of geometrical model of Saccharomycescerevias treated by high pressure.We studied effect of difference pressure and variance time tocell killing of Saccharomyces cerevias, probed relation of highpressure and beer yeast mutagenesis.Then it was found thatSaccharomyces cerevias had higher mu-tation rate at the pressureof 200-200MPa within 30 mins. So this could be the best treatingparameters. We obtained an anti-high-pressure and anti-high-temperature variation, MS-2-2 with the treation.With the method of molecular biology, we analyzed and studiedthe difference at the level of DNA and Protein between the va-riation strain MS-2-2 induced by high pressure and the comparisonstrain by means of RAPD-PCR and SDS-PAGE. The result showed thatthere were some variant character bandings in the five RAPD primersamplifications of the total seven primers amplactions.And theresult of SDS-PAGE also showed that there were more one about 49KDprotein bandings of MS-2-2 than the com-parison strain. The genomeDNA of Saccharomyces cerevias treated by high pressure had occuredinsert, deletion and basic group mutation etc. And this had affectedthe structure,function,expression of gene. High pressure hadinduced expression of some genes and facilitated some proteinssynthesis such as PIPs(Pressure Induced Proteins). At last, the workof future had been prospected.
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