Team:UM Macau
Abstract
Gout is a common rheumatic disease. Symptoms include swollen, red, hot, and stiff joints. The accumulated purine in beer is one of the reasons that causes gout after drinking beer. Low purine beer, therefore, can reduce the risk of beer drinkers suffering from gout. Meanwhile, oxidation in beer causes off-flavors and darkened color. Based on these problems, our team hence proposed to edit the yeast used in beer fermentation in order to produce a beer with low purine content and good antioxidant properties. We engineer the wild-type yeast by synthetic biology method such that the engineered yeast is able to produce and secrete three enzymes--purine nucleoside phosphorylase1 (PNP1), superoxide dismutase 1 (SOD1), and endochitinase (chit42). The PNP1 can convert purine polynucleotides into purine bases that can be directly used by yeast, thereby improving the utilization of purines by yeast and ultimately reducing the purine content in beer. The SOD1 and endochitinase will increase antioxidation in the final product.