Dr. Shen-Long Tsai
Associate Professor, Department of Chemical Engineering, National Taiwan University of Science and Technology, Taiwan, China

Speech Title: Genetically Engineered Saccharomyces cerevisiae for enhanced ethanol production from heavy metal-contaminated substrates

Abstract: New energy sources and their production are attracting increased attention due to the issue of energy crisis. Cellulosic ethanol is an emerging liquid energy to replace the fossil fuels that we are using nowadays. The aim of this work was to study the feasibility of surface displaying synthetic phytochelatin (EC) on Saccharomyces cerevisiae to overcome the inhibitory effect of heavy metals on ethanol production. Via the fusion of a gene encoding EC to an α-agglutinin gene, the engineered S. cerevisiae was able to successfully display EC on its surface. This surface engineered yeast strain exhibited an efficient cadmium adsorption capability and a remarkably enhanced cadmium tolerance. Moreover, its ethanol production efficiency was significantly improved as compared to a control strain in the presence of cadmium. Similar results could also be observed in the presence of other metals, such as nickel, lead and copper. Overall, this method allows simultaneous biorefinery and heavy metal removal when using heavy metal-contaminated biomass as raw materials.