International Research Fellowship Program: Biomass-Derived Fuels: Modeling and Simulation of Enzymatic Processes

国际研究奖学金计划使美国科学家和工程师能够在国外进行9到24个月的研究。 该计划的奖项提供了合作研究的机会，以及使用国外独特或互补的设施，专业知识和实验条件。该奖项将支持Jim Pfaendtner博士与瑞士苏黎世ETH的Michele Parrinello博士合作进行为期24个月的研究奖学金。确保清洁，可再生能源的充足供应无疑是科学家在本世纪面临的最大挑战之一。 化石燃料的惊人消费加剧了气候变化和地缘政治不稳定，而且是非常不可持续的。 实际上，由于西方和发展中国家石油供应有限，石油消费增长率高，因此没有解决即将到来的“能源危机”的办法。 据估计，我们的能源组合目前仅包含8%的可再生能源，但这一贡献必须在未来大幅增长，以满足社会的能源需求。 可再生能源组合的一个主要增长领域将来自生物质衍生燃料。 目前阻止生物质在燃料生产中广泛使用的两个主要障碍是1）减缓催化的非生产性木质素-酶结合和2）缺乏可以消化植物细胞内的坚固材料的有效酶。实验技术本身不能充分解决这些问题，由于在测量速率的基本反应和酶运动的时间尺度上的动力学的困难。 所提出的工作的目的是开发一个新的建模框架，使用粗粒度的分子模拟和新的自由能采样方法来探测这些现象。 PI和主机正在构建新的多尺度模型，将原子级信息传播到与生物燃料生产相关的时间/长度尺度。 这种新的建模框架被用于研究木质素/纤维素酶系统中的结构-性质关系以及研究内切-β-1，4-木聚糖酶对木聚糖的酶促消化。这项工作对社会的明显影响将是更好地了解如何从生物质中获得可持续燃料。 社会在生活的各个方面都对能源和燃料有着巨大的依赖。 除了燃烧化石燃料，我们目前还没有开发出可以满足我们能源需求的技术。 因此，开发可持续燃料对维持我们的生活方式至关重要。

0700080PfaendtnerThe International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will support a twenty-four-month research fellowship by Dr. Jim Pfaendtner to work with Dr. Michele Parrinello at ETH in Zurich, Switzerland.Securing an abundant supply of clean, renewable energy is without question one of the greatest challenges facing scientists in this century. The alarming consumption of fossil fuels contributes to climate change and geopolitical instability and, moreover, is highly unsustainable. In practical terms, there is no solution to the coming ``energy crunch'', given limited supplies and the high growth rate in oil consumption in the west and the developing world. Our energy portfolio now contains, by some estimates, as little as 8% from renewables, but this contribution must grow dramatically in the future in order to address the energy needs of society. One main area of growth in the renewable energy portfolio will be from biomass-derived fuels. Two main obstacles currently preventing the broad use of biomass in the production of fuels are 1) non-productive lignin-enzyme binding that slows catalysis and 2) the lack of efficient enzymes that can digest robust materials within plant cells. Experimental techniques alone cannot sufficiently address these problems due to difficulties in measuring the rates of elementary reactions and enzyme motions on the time scale of their dynamics. The object of the proposed work is to develop a new modeling framework to probe these phenomena using coarse-grained molecular simulation and new free-energy sampling methods. The PI and host are building new multiscale models that propagate atomic-level information to time/length scales relevant to the production of biofuels. This new modeling framework is being used to study structure-property relationships in the lignin/cellulase system as well as to investigate the enzymatic digestion of xylan by endo-beta-1,4-xylanase. The clear impact of this work on society will be an improved understanding of how to obtain sustainable fuels from biomass. Society has an enormous dependence on energy and fuels in all aspects of life. Other than burning fossil fuels, we currently have no developed technologies that can meet our energy needs. As such, developing sustainable fuels is critically important in sustaining our way of life.