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联合研究的机会，并利用国外独特或互补的设施、专业知识和实验条件。该奖项将支持吉姆·普芬特纳博士与瑞士苏黎世理工学院的米歇尔·帕里内洛博士合作的为期24个月的研究奖学金。确保充足的清洁、可再生能源供应无疑是本世纪科学家面临的最大挑战之一。令人震惊的化石燃料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，鉴于西方和发展中国家的石油供应有限，石油消费增长率很高，没有办法解决即将到来的“能源危机”。据估计，我们的能源组合现在只有8%来自可再生能源，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。目前阻碍生物质在燃料生产中广泛使用的两个主要障碍是：1)非生产性木质素-酶结合减慢了催化速度；2)缺乏有效的酶来消化植物细胞内的强健物质。单靠实验技术不能充分解决这些问题，因为很难在动力学的时间尺度上测量基元反应和酶的运动速度。这项工作的目的是开发一种新的建模框架，使用粗粒度分子模拟和新的自由能采样方法来探索这些现象。国际和平研究所和东道主正在建立新的多尺度模型，将原子水平的信息传播到与生物燃料生产相关的时间/长度尺度。这个新的建模框架被用来研究木质素/纤维素酶体系的结构-性质关系，以及内切-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理解如何从生物质中获得可持续燃料。社会在生活的方方面面都对能源和燃料有巨大的依赖。除了燃烧化石燃料外，我们目前还没有开发出能够满足我们能源需求的技术。因此，发展可持续燃料对于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.