Development of Synthetic Yeast for Enzymatic Pretreatment of Lignocellulosic Biomass
The production of some biofuels is inhibited by lignin, a complex organic polymer which physically blocks carbohydrate substrates and inhibits biomass degrading enzymes (BDEs). A common biofuel practice is to sequester lignin using energy-intensive thermal pretreatment. The recent development of a synthetic yeast that spatially separates lignin degradation products from vulnerable BDEs enables an efficient lignin breakdown system to reduce the energy input for biofuel production. By expressing enzymes from lignin-degrading species (termites and white rot fungi), we aim to establish a novel enzymatic pretreatment system in a yeast chassis. Six enzymes were selected for their ability to operate at room temperature and standard pH. The expressed enzymes were evaluated individually and in combination for lignin-degradation efficiency. Furthermore, we designed an additional vector to contain our genetically modified yeast using an oxygen-repressed killswitch.