New catalytic functions for [4Fe-4S] clusters

这一无机化学、生物无机和金属有机化学项目以及分子和细胞生物学项目的研究奖支持了阿拉巴马州奥本大学的Eduardus(Evert)C.Duin教授的工作，他探索了1-脱氧-D-木糖-5-磷酸(DOXP)途径中倒数第二和最后的蛋白质GcpE和LytB的反应机制，以及它们的活性部位铁-硫簇在这一过程中的作用。动力学实验将深入了解几个瞬时EPR活性物种在反应机理中的作用。这些物种将使用EPR/Endor光谱和衬底结构中选定原子的同位素标记相结合的方式进行表征。此外，我们还将通过底物调节研究进一步了解这些酶的作用机制。结合数据将提供对GcpE和LytB酶的机制的完整了解。由于这两种酶似乎都参与了一种全新的催化，这将是对铁硫领域的一项重要贡献。此外，这一知识将有助于生物技术的商业化，因为它增加了生产具有商业价值的异戊二烯类化合物的难度，并开发了对人类危害较小的新型除草剂。这笔资金还通过购置用于快速混合/快速冷冻研究的设备，支持生物化学处的研究和教学工作。

This Research award in the Inorganic, Bioinorganic and Organometallic Chemistry program and the Molecular and Cellular Biology program supports work by Professor Eduardus (Evert) C. Duin at Auburn University, Alabama, to probe the reaction mechanism of the penultimate and ultimate proteins in the 1-deoxy-D-xylulose-5-phosphate (DOXP) pathway, GcpE and LytB, and the role of their active-site iron-sulfur clusters in this process. Kinetic experiments will provide insight in the role of several transient EPR-active species in the reaction mechanisms. The species will be characterized using the combination of EPR/ENDOR spectroscopies and isotopic labeling of selected atoms in the substrate structures. In addition further details on the mechanisms of the enzymes will be obtained through substrate modulation studies. The combined data will provide a complete understanding of the mechanisms of the GcpE and LytB enzymes. Since both enzymes seem to be involved in a completely new type of catalysis this will be an important contribution to the iron-sulfur field. In addition, this knowledge will benefit the commericialization of biotechnology through increased ease of production of commercially interesting isoprenoids and the development of novel herbicides that are less harmful to humans. The funding also supports the Biochemistry division research and teaching efforts through the acquisition of equipment for rapid-mix/rapid freeze studies.