Genome-wide Study For Genes Involved In Furfural Tolerance In Saccharomyces Cerevisiae

The dependence on fossil energy resources has been extended to all aspects ofdaily life. However, the price and supply system of the fossil energy in the worldtoday is not stable. In addition, the sustainable development and environmentalprotection is a major focus, with the renewable energy production receiving more andmore attention. Ethanol can contribute to energy. It is clear that large-scale use ofethanol for fuel will require bioconversion of lignocellulose derived from agriculturewastes, municipal solid wastes and wastes from paper industries. Nonetheless, manytechnological obstacles need to be addressed in this bioconversion production. One ofthese is the presence of multiple inhibitors, including furfural, produced during theinitial pretreatment.From a genome-scale genetic screening, we found that163gene disruptionmutants were identified to be tolerant to10mM furfural in Saccharomyces cerevisiae.These genes function in a wide spectrum of physiological pathways, suggesting thatfurfural tolerance is a complex biological process. About eleven percent of the163genes are involved in cellular transport, ten percent involved in metabolism, and ninepercent in cell cycle and DNA processing. Proteins encoded by most of theses genesare localized in the mitochondrion; some are in the cytoplasm and the nucleus.We focused on the DEP1, SIZ1and SAP30, whose corresponding mutants,siz1/siz1, dep1/dep1, sap30/sap30and siz1, dep1, sap30were identified as the mosttolerant mutants with approximately100×increased growth in comparison to thecorresponding wild-type. We constructed their double mutants, siz1dep1, siz1sap30and dep1sap30, and found that siz1dep1and siz1sap30double mutants are lesstolerant than their single mutants, demonstrating that SIZ1interacts with DEP1andSAP30in furfural tolerance.