Effect Of Key Enzymatic Gene Deletion In Saccharomyces Cerevisiae On Glutathione Synthesis And Amino Acids Synthesis

Glutathione is a tripeptide compound,it is condensed from L-glutamate,L-cysteine and glycine,containing biological activity bothγ-glutaminyl and sulfhydryl. Glutathione have a variety of important physiological functions in the body,especially plays a vital role for maintaining appropriate redox environment in organisms,and share a wide range of uses in the area of clinical medicine,food industry,sports and biological research.Cystathionineβ-synthase(β-CTSase)and cystathionineγ-lyase(γ-CTLase) are the key enzyme on cysteine biosynthesis in Saccharomyces cerevisiae,the corresponding regulated genes are CYS3 and CYS4,γ-glutamyl cysteine synthetase and glutathione synthetase are the key enzyme on glutathione biosynthesis in Saccharomyces cerevisiae,the corresponding regulated genes are GSH1 and GSH2,CYS3,CYS4 and GSH1,GSH2 deletion strains were constructed by homologous recombination method.Then we examined glutathione metabolism and amino acids metabolism production and compared them to relative production of wild strain of Saccharomyces cerevisiae,figuring out the effect on glutathione metabolism and amino acids metabolism after the deletion the gene of CYS3,CYS4 and GSH1,GSH2. The purpose was to know the effect of key genes on glutathione and amino acids synthesis by gene deletion in Saccharomyces cerevisiae.According to the laboratory result,compared with the wild strain,the yield of glutathione in the CYS3 deletion strain reduced by 26.1%,the yield of glutathione in the CYS4 deletion strain increased by 6%,the yield of glutathione in the GSH1 deletion strain reduced by 18.5%,the yield of glutathione in the GSH2 deletion strain reduced by 4.17%.These data,together with data of other glutathione synthesis related genes,can be established network of Saccharomyces cerevisiae glutathione metabolism systems biology model.