Biomass recalcitrance, the use of enzymes and their component-parts to better elucidate cellulose amorphogenesis and fiber structure

生物质顽抗性，使用酶及其组成部分更好地阐明纤维素无定形发生和纤维结构

• 批准号: RGPIN-2014-04965
• 负责人: Saddler, Jack(John)
• 金额: $ 3.21万
• 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: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=588123
• 关键词: Biomass; recalcitrance; use; enzymes; their

The innate resistance of lignocellulosic materials, particularly the cellulosic component, to enzymatic and chemical attack is due to the physical, mechanical and chemical structures/mechanisms that nature has evolved in these materials to prevent access and disassembly of the plant cell wall’s major components. This is problematic if we hope to deconstruct biomass substrates to valuable chemical intermediates or to modify them to enhance their fiber properties. The work described in the detailed proposal hopes to make use of our expertise in pretreatment/pulp modification, enzyme characterization/action and enzyme-substrate interaction to better understand the physical, mechanical and chemical impacts of fiber structure and to see if poorly understood mechanisms such as the suggested “amorphogenesis” step of cellulose deconstruction can be better elucidated. To do this we will produce a range of pretreated and highly characterized biomass/pulp substrates (using our steam pretreatment, organosolv and pulping equipment) and traditional pulp and paper methods (coarseness, fiber strength, FQA, Kajani, etc.) as well as methods we have developed or refined in our lab (Simons Stain, use of Cellulose Binding Modules for amorphous/crystalline regions of cellulose) to assess changes in the biomass substrate. We will also make use of crystalline nanocellulose (CNC), nanofibrillated cellulose (NFC) and cellulose filaments (CF) substrates that have been produced and characterized by colleagues at the US Forest Products Lab, FP Innovations, Inventia, Alberta Innovates, etc. We will use individual and cocktails of enzymes and their component-parts, such as swollenin, expansin, CBM’s, (both produced and purified in house as well as supplied by collaborators in industry and in other research groups) to investigate the relationship between biomass structure, ultrastructure, composition and resistance to enzymatic modification and deconstruction. The overall goal is to develop a better understanding of enzyme mediated biomass deconstruction/modification. The work will strengthen the synergies between pretreatment/pulping processes and enzymatic modifications to improve both the fiber characteristics of cellulosic materials (such as increasing their absorbency or strength) and the potential of the biomass-derived sugar platform (by increasing the rate and completeness of cellulose hydrolysis). It is hoped that, with a better understanding of mechanisms such as enzyme-mediated amorphogenesis, this will help us both better understand how biomass deconstruction/delamination/disaggregation might occur and help with potential applications such as producing super adsorbent pulp/tissue paper or more easily degraded biomass substrates that could form that bases of a biochemically based sugar platform for fuels and chemicals production.

木质纤维素材料，特别是纤维素成分，对酶和化学攻击的先天抗性是由于自然在这些材料中进化出的物理、机械和化学结构/机制，以防止植物细胞壁的主要成分进入和分解。如果我们希望将生物质基质分解为有价值的化学中间体或对其进行改性以增强其纤维性能，这是有问题的。详细提案中描述的工作希望利用我们在预处理/纸浆改性，酶表征/作用和酶-底物相互作用方面的专业知识，更好地了解纤维结构的物理，机械和化学影响，并看看是否可以更好地阐明纤维素解构的“非形态发生”步骤等尚不清楚的机制。为此，我们将生产一系列预处理和高度表征的生物质/纸浆基材（使用我们的蒸汽预处理、有机溶剂和制浆设备）、传统的纸浆和造纸方法（粗度、纤维强度、FQA、Kajani等）以及我们在实验室开发或改进的方法（Simons Stain，使用纤维素结合模块用于纤维素的非晶/结晶区域），以评估生物质基材的变化。我们还将利用晶体纳米纤维素（CNC）、纳米纤化纤维素（NFC）和纤维素细丝（CF）底物，这些底物已经由美国森林产品实验室、FP Innovations、Inventia、Alberta Innovates等公司的同事生产和表征。我们将使用单独的和混合的酶及其组成部分，如膨化酶、膨胀酶、CBM，（既可以在内部生产和纯化，也可以由工业和其他研究小组的合作者提供）来研究生物质结构、超微结构、组成和对酶修饰和解构的抗性之间的关系。总体目标是更好地理解酶介导的生物质解构/修饰。这项工作将加强预处理/制浆过程和酶修饰之间的协同作用，以改善纤维素材料的纤维特性（如增加其吸收性或强度）和生物质衍生糖平台的潜力（通过提高纤维素水解的速度和完整性）。人们希望，随着对酶介导的非形态发生等机制的更好理解，这将有助于我们更好地理解生物质解构/分层/分解可能发生的机制，并有助于潜在的应用，如生产超吸附性纸浆/薄纸或更容易降解的生物质底物，这些底物可以形成用于燃料和化学品生产的基于生化的糖平台的基础。