Toward Artificial Enzyme Analogues for Cellulose Hydrolysis Using High-throughput Screening

1033017李的知识产权优点一种可持续和环境友好的乙醇运输燃料来源是纤维素，这是木质纤维素植物生物质的主要成分。 纤维素水解产生葡萄糖，葡萄糖可发酵成乙醇。 然而，通常，纤维素的水解是困难的过程，并且目前是纤维素至乙醇转化中的限速步骤。 具有非常特异的催化结构的纤维素酶能够有效地水解纤维素而不形成副产物。 然而，酶是相对缓慢的，热不稳定的，并且昂贵，因为它们必须是生物产生的，不容易重复使用。这项研究将开发和理解可以水解纤维素及其亚基的人工酶类似物的功能。 基于溶胶-凝胶法，将纤维素低聚物分子印迹到有机-无机杂化固体催化剂载体上，将产生人工酶结构。 这种策略具有潜在的联合收割机的效率和特异性的蛋白质为基础的酶的鲁棒性和成本效益的非均相固体catalysts.In拟议的研究中，人工酶类似物的水解纤维素低聚物和纤维素将产生基于分子印迹溶胶-凝胶技术结合高通量的合成和筛选方法。 印迹过程产生的分子空腔将为纤维素亚基提供特异性结合域，以及糖苷键水解所需的固体酸位点。 为了潜在地增强底物水解并促进分子印迹催化剂和底物之间的诱导配合，将通过向溶胶-凝胶基质中添加有机硅烷来调节溶胶-凝胶催化剂的柔性。 据推测，分子印迹催化剂的特异性将阻碍导致葡萄糖降解的副反应，这是常规固体酸催化剂的主要问题。高通量的方法将能够筛选大量（~ 10，000）的合成参数，以优化分子印迹催化剂的组成和结构。更广泛的影响拟议的教育和推广活动的目的是激发学生对生物质能源和科学和工程的基本思想的兴趣。 通过路易丝·斯托克斯少数民族参与联盟（AMP）夏季本科生研究计划招募的代表性不足的群体的本科生将有机会参与研究。 作为推广计划的一部分，PI将与当地有线电视台合作，开发关于能源现状和开发可再生能源技术重要性的节目。 这个科学节目将在整个费城都会区播出。

1033017LeeIntellectual MeritsA sustainable and environmentally friendly source of ethanol for transportation fuel is cellulose, which is the major component of lignocellulosic plant biomass. Hydrolysis of cellulose generates glucose, which can be fermented to ethanol. However, in general, the hydrolysis of cellulose is a difficult process, and is currently the rate-limiting step in the cellulose-to-ethanol conversion. Cellulase enzymes with very specific catalytic structures are capable of efficient cellulose hydrolysis without byproduct formation. However, enzymes are relatively slow, thermally unstable, and expensive, as they must be biologically produced are not readily reusable. The proposed research will develop and understand the function of artificial enzyme analogues that can hydrolyze cellulose and its subunits. Artificial enzyme structures will be created by molecular imprinting of cellulose oligomers onto organic-inorganic hybrid solid catalyst supports based on sol-gel methods. This strategy has the potential to combine the efficiency and specificity of protein-based enzymes with the robustness and cost effectiveness of heterogeneous solid catalysts.In the proposed research, artificial enzyme analogues for hydrolysis of cello-oligomers and cellulose will be generated based on a molecular-imprinting sol-gel technique combined with a high-throughput synthesis and screening method. Molecular cavities generated by the imprinting process will provide specific binding domains for sub-units of cellulose as well as solid acid sites required for hydrolysis of glycosidic bonds. To potentially enhance substrate hydrolysis and promote induced fit between the molecularly imprinted catalyst and substrate, the flexibility of the sol-gel catalysts will be tuned by adding organo-silanes to the sol-gel matrix. It is hypothesized that the specificity of the molecularly-imprinted catalysts would hinder side reactions that lead to degradation of glucose, which is a major problem with conventional solid-acid catalysts. The high throughput method will be able to screen a large number (~10,000) of synthesis parameters to optimize the composition and structure of the molecularly-imprinted catalysts.Broader ImpactsThe proposed education and outreach activities are designed to stimulate student interest in biomass energy and fundamental ideas in science and engineering. Undergraduate students from underrepresented groups recruited through the Louise Stokes Alliance for Minority Participation (AMP) Summer Undergraduate Research Program will be given opportunities to participate in the research. As part of the outreach plan, the PI will work with a local cable access TV station to develop programming on the current state of energy landscape and the importance of developing renewable energy technologies. This scientific program will be aired throughout the Philadelphia metro area.