Proteomic Analysis Of Saccharomyces Cerevisiae Cultured At Extreme Survival Temperature

Saccharomyces cerevisiae is the the optimal model in which to study mammalian cellular control under stress conditions,yeast is also utilized widely as a biotechnological tool in the alcohol industry, food industry and pharmaceuticals industry. Fundamental researches on Saccharomyces cerevisiae is considered to be a supporter to eukaryote organism.The evolutionary conservation between organisms and the universal distribution of general stress responses make the budding yeast Saccharomyces cereisiae an ideal model system to investigate the ways in which cells adjust to changes in their environment. In fact, yeast has the same defence mechanisms as higher eukaryotes.The outward manifestation of these changes is the physiological-biochemical characteristic,but the immanent cause is the expression level of dormant genes. All these adjustments depend on proteins which acts a key role.In this paper we wish to find out the proteomic changes under high temperature stress,and so we can characterize it through mass spectrum, then identify the amino acid sequence and gene sequence.Recent research almost focus on the intercellular proteom,here we study on the intercellular,extracellular and cell wall proteom from Saccharomyces cerevisiae.In our pre-exams, we acclimatize the Saccharomyces cerevisiae FFC2146to high temperature,find extreme survival temperature is42℃,and we chose40℃as the culture temperature to collect proteins more efficient.Extracellular proteins was concentrated by non-denatured ultrafiltration.Proteomic analysis of yeast extracellular proteins which cultured at normal(28℃) and extreme high(42℃) temperatures was observed by Two-dimensional electrophoresis. Results shows that, about140spots was detected,52proteins’ expression changed between these two culture conditions, and2family of Glycogen is demonstrated by PAS stain,the changes of expression levels among these proteins show the regulation to environment.The sedimentation rat of yeas cells cultured at28℃and40℃was inspected,results shows that high temperatures accelerates cell sedimentation. Proteins of cell wall were obtained by dithiothreitol and phenol abstraction,about470protein spots was found in2-DE images by PDQuest software,among these19proteins which connected to sedimentation change its’density between two conditions.The growth velocity,glucose concentration and ethanol concentration was detected during fermentation at28℃and40℃.results shows that all these three index were more lower at40℃,high temperature is liability to yeast growth. Intercellular proteins of yeast culture at28℃and40℃collected by ultrasonic cleavage.Two-dimensional electrophoresis was performed to analysis the difference between these two condition.About330protein spots was observed,6protein changed there expression level.Those proteins release to Metabolism of grape and heat shock.Finally, analysis of these2-DE images from three different location of Saccharomyces cerevisiae FFC2146,indicate that yeast shows high ability in adjustments to environment stress through control the expression level of intercellular,cell wall and extracellular proteins.But the variation range of those three proteins are different:the cell wall proteins changes more than intercellular one,and the extracellular proteins changes more than cell wall proteins during self regulation responsed to environment stress.