Developing biocatalysts to valorize lignin

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The Canadian forest products industry must undergo a paradigm shift to remain competitive, due to competition from abroad and the plummeting demand for traditional products. Meanwhile, there is burgeoning demand for environmentally-sustainable bioproducts. Next generation lignocellulosic biorefineries producing renewable fuels, commodity and feedstock chemicals, and biomaterials will drive the requisite shift. This shift will require that lignin, comprising 15-30% of woody biomass, be converted to higher value products. Our project will develop biocatalysts for the deconstruction and conversion of lignin into bioproducts. Such "biocatalysts" can unlock the enormous economic potential of Canada's forest biomass, usher in production of new value-added products, and substantially reduce the industry's ecological footprint. We aim to develop two types of biocatalysts: (a) enzymes that depolymerize lignin; and (b) bacteria that transform lignin depolymerization products to high-value products. These objectives will be achieved using cutting-edge methods pioneered in our laboratories. Lignin depolymerization activities will be mined using metagenomic and activity-based screens of microbial communities that naturally decompose biomass. Degradation pathways for lignin depolymerization products in bacteria will be discovered using genomic approaches. The genes encoding relevant enzymes and pathways will constitute a toolkit to develop biocatalysts and processes that valorize lignocellulosic biomass. With this toolkit, we will engineer bacteria to upgrade lignin-derived streams to commodity chemicals, such as wax esters and muconate. We will collaborate with our industrial partners to identify appropriate bioproducts, to integrate our biocatalysts in engineered systems under development, and to commercialize the resulting technologies. Our partners include FPInnovations, Fibria, Catalyst Paper, the National Renewable Energy Laboratory (NREL) and AB Enzymes. These organizations are developing technologies to improve the biorefining of biomass and are poised to take up novel lignin-transforming biocatalysts.