A Novel Strategy For Enhancing Bioethanol Production By Saccharomyces Cerevisiae By Using Molecular Biology Methods

During the last few years,the Global Transcription Machinery Engineering(gTME)technique has gained more attention as an effective approach for the construction of novel mutants.Genetic strategies(molecular biology methods)were utilized to get mutations for both genes(SPT15 and TAF23)basically existed in the Saccharomyces cerevisiae(S.cerevisiae)genome via screening the libraries produced by gTME approach in order to obtain a new mutant S.cerevisiae diploid strain.The vector pYX212 was utilized to transform these genes into the control diploid strain S.cerevisiae through the process of mating between haploids control strains S.cerevisiae(MAT-a [CICC 1374])and(MAT-? [CICC 31144]),by using the oligonucleotide primers SPT15-EcoRI-FW / SPT15-Sal I-RV and TAF23-Sal I-FW/ TAF23-Nhe I –RV,respectively.The resultant mutants were examined for a series of stability tests.This study showed how strong the effect of using strategic gTME with the importance of the modification we conducted in error-prone polymerase chain reaction(Ep-PCR(protocol by increasing MnCl2 concentration instead of MgCl2.More than ninety mutants we obtained in this study were distinguished by a high-level production of bioethanol as compared to the diploid control strain.Mutants recorded the highest ethanol production by using 3 % MnCl2 with improving the yield rate to 60.24 % compared to R-control strain.