Biovalorization of lignin

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Canada is home to 12% of the world's forests and the forestry sector contributes roughly $25 billion to our economy each year. This industry also directly employs over 200,000 Canadians. Large as these numbers are, though, the Canadian forestry sector has been in a state of sustained decline over the past few years. Society's embracement of the electronics age has meant that Canadians simply do not consume pulp and paper products, which comprise over a third of the output of Canadian forest, to the same extent as they did a generation earlier. The sector's other major offering, softwood lumber, is a high-volume, low-value product with thin margins. Even if demand for Canadian softwood lumber were to increase substantially - which, incidentally, is not the case - it is unlikely to add more value to the Canadian economy. It is imperative that the Canadian forestry sector modernize itself and become more technologically intensive if it is to regain its lost glory. Calculations suggest that transitioning away from traditional lumbering operations and instead developing and implementing novel chemical and biocatalytic processes to produce low-volume, high-value products such as pharmaceuticals, biomaterials, polymers and personal care products would not only exponentiate the economic contribution of the sector and generate more, higher paying jobs, but also preserve Canada's forests and reduce the environmental footprint of the sector. The production of value-added products such as pharmaceuticals currently comprises about 1% of the sector's GDP. The current proposal seeks to develop novel biocatalysts and bioprocesses to convert lignin, a major constituent of forest biomass, into pharmaceuticals and spice ingredients. Lignin makes up a third of forest biomass but is a highly recalcitrant material that is typically burned for energy. There are very few commercial processes that can convert lignin into valuable products and our inability to utilize lignin is a lost opportunity for the green economy. The first family of biocatalysts that we will develop will selectively degrade lignin to its monoaromatic constituents. The second family of biocatalysts will then modify the monoaromatic constituents to desired target molecules. Biocatalytic processes are greener, emit lesser carbon dioxide and are more energy efficient than other alternatives. In the long term, we will manipulate the metabolic network of the bacterium E. coli to express the novel biocatalysts. The engineered strains will then be employed in consolidated bioprocesses that convert lignin into value-added chemicals. We will also work closely with our existing industrial collaborators to translate our innovations to the market. In summary, the proposed research will not only facilitate monetization of a recalcitrant and hitherto worthless waste stream, but will also reduce the environmental footprint and revitalize the forestry sector in Canada.