Developing biocatalysts to valorize lignin

由于来自国外的竞争和对传统产品的需求急剧下降，加拿大林产品工业必须进行范式转变，以保持竞争力。与此同时，对环境可持续的生物产品的需求也在迅速增长。下一代生产可再生燃料、商品和原料化学品以及生物材料的木质纤维素生物精炼厂将推动必要的转变。这一转变需要将占木质生物质15-30%的木质素转化为更高价值的产品。我们的项目将开发用于木质素分解和转化为生物产品的生物催化剂。这样的“生物催化剂”可以释放加拿大森林生物质的巨大经济潜力，迎来新的增值产品的生产，并大幅减少该行业的生态足迹。我们的目标是开发两种类型的生物催化剂：(a)解聚木质素的酶；(b)将木质素解聚产物转化为高价值产品的细菌。这些目标将使用我们实验室开创的尖端方法来实现。木质素解聚活性将利用自然分解生物量的微生物群落宏基因组和基于活性的筛选来挖掘。木质素解聚产物在细菌中的降解途径将使用基因组方法被发现。编码相关酶和途径的基因将构成一个工具包，用于开发使木质纤维素生物质增值的生物催化剂和过程。有了这个工具包，我们将设计细菌将木质素衍生的流升级为商品化学品，如蜡酯和黏液酸盐。我们将与我们的工业伙伴合作，确定合适的生物产品，将我们的生物催化剂整合到正在开发的工程系统中，并将由此产生的技术商业化。我们的合作伙伴包括FPInnovations， Fibria, Catalyst Paper，国家可再生能源实验室（NREL）和AB酶。这些组织正在开发技术，以改善生物质的生物精炼，并准备采取新的木质素转化生物催化剂。

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.