Bacterial lignin degradation: characterization and biocatalytic applications

细菌木质素降解：表征和生物催化应用

• 批准号: RGPIN-2018-04867
• 负责人: Eltis, Lindsay
• 金额: $ 4.23万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=690756
• 关键词: Bacterial; lignin; degradation; characterization; biocatalytic

Bacteria are responsible for most of the degradation of natural and human-made compounds in the biosphere. This degradation constitutes an essential link in the global carbon cycle and is critical to sustaining life on our planet. Bacterial degradation activities also represent a rich, barely tapped source of biocatalysts to sustain the emerging global bioeconomy. Over the past two decades, my NSERC-funded research program has provided novel insights into the function of bacterial enzymes involved in the degradation of aromatic compounds and pollutants as well as into how these enzymes are regulated. Over the next five years, I will focus my program on enzymes that degrade lignin, a complex aromatic polymer that comprises about 25% of the land-based biomass. Lignin occurs in tight association with cellulose and hemicellulose to form the strong, rigid structure that is very resistant to degradation. Deconstructing this lignocellulose is critical to using woody biomass as a renewable source of chemicals, materials and other bioproducts. While fungal enzymes that degrade lignin have been studied for years, bacterial lignin-degrading enzymes have been largely overlooked despite being more amenable for industrial processes. My research will focus on two types of bacterial enzymes that: (a) breakdown the polymeric lignin; and (b) degrade the lignin depolymerization products. These enzymes represent important classes of metal-containing enzymes that are not well understood. The proposed research will increase our understanding of what these enzymes do and how they do it. This will in turn provide fundamental insights into the molecular mechanism of important biological processes as well as how Nature uses metals to catalyze these processes. The knowledge gained will also facilitate the engineering of enzymes and bacteria for biotechnological applications. More particularly, it will help in the design of biocatalysts to transform low-value lignin into high-value materials, such lubricants, cosmetics and bioplastics. The research objectives will be achieved using an interdisciplinary approach involving a variety of cutting-edge techniques. The research will benefit from a number of tools and approaches developed in the Eltis lab. Finally, the research program provides trainees with a wide range of skills, preparing them for fulfilling careers in academia, industry and government.

细菌负责生物圈中天然和人为化合物的大多数降解。这种退化构成了全球碳周期中的重要联系，对于维持我们星球上的生命至关重要。细菌降解活性也代表了维持新兴的全球生物经济学的丰富，几乎没有利用的生物催化剂来源。在过去的二十年中，我由NSERC资助的研究计划提供了对参与芳香族化合物和污染物降解的细菌酶功能的新见解，以及这些酶如何调节这些酶的功能。在接下来的五年中，我将重点放在降解木质素的酶上，该酶是一种复杂的芳香族聚合物，约占陆基生物量的25％。木质素与纤维素和半纤维素密切相关，形成了非常耐降解的强，刚性结构。解构该木质纤维素对于使用木质生物量作为可再生化学物质，材料和其他生物产品的来源至关重要。尽管多年来研究了降解木质素的真菌酶，但细菌木质素降解酶仍被忽略了，尽管更适合工业过程。我的研究将集中在两种类型的细菌酶上：（a）分解聚合物木质素； （b）降解木质素解聚产物。这些酶代表了含金属的重要类酶，这些酶尚不清楚。拟议的研究将提高我们对这些酶的理解以及它们如何做到的。反过来，这将提供对重要生物学过程的分子机制以及自然如何使用金属催化这些过程的基本见解。获得的知识还将促进生物技术应用的酶和细菌的工程。更特别的是，它将有助于设计生物催化剂，以将低价值木质素转化为高价值材料，例如润滑剂，化妆品和生物塑料。将使用涉及各种尖端技术的跨学科方法来实现研究目标。该研究将受益于ELTIS实验室中开发的许多工具和方法。最后，该研究计划为受训者提供了广泛的技能，为他们的学术界，工业和政府的职业做好准备。