Evolving Hemoproteins for New-to-Nature Ring-Forming Reactions

具有环状结构的分子存在于从药物到塑料的所有物质中，它们的特殊结构赋予了重要的功能特性。发现和开发这种分子和材料的瓶颈通常是从简单的起始材料构建复杂环的能力有限。该项目建立了强大的和可推广的酶途径，以不同的环结构，使用化学以前不知道在生物催化。这种新的天然成环酶完全由基因编码，使用地球上丰富的铁，在温和的条件下发挥作用，可持续生产各种材料，药物和化学品。这个跨学科的项目培养了非常有才华的研究生和博士后研究员在可持续化学，生物技术和生物工程的学术和工业研究。本研究是在首席研究员成功地将血红素蛋白用于新的卡宾和氮烯转移反应的基础上，通过定向进化新的酶催化剂，将其扩展到发现和优化。这些催化剂用于制备使用合成化学难以制备的环结构。优化了分子内卡宾和氮烯C-H插入反应，以获得重要的含环分子，如内酰胺，内酯和环胺。在许多情况下，这些转化没有等效的小分子催化剂，因此它们将首次以催化方式实现。进化的生物催化剂的效用进行了评估，在合成和后期阶段的生物活性分子和先进材料的前体的修改。该研究还包括动力学，光谱，结构和计算研究，以阐明酶成环反应的机制，并支持进一步的酶工程或小分子催化剂的开发。该项目由分子和细胞生物科学部的系统和合成生物学集群，化学，生物工程部的细胞和生物化学工程项目，该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Molecules with ring structures are found in everything from drugs to plastics, where their special structures confer important functional properties. The bottleneck for discovering and developing such molecules and materials is often a limited ability to build complex rings from simple starting materials. This project establishes powerful and generalizable enzymatic routes to diverse ring structures, using chemistry not previously known in biological catalysis. The new-to-nature ring-forming enzymes are entirely genetically encoded, use earth-abundant iron, and function under mild conditions for sustainable production of a variety of materials, pharmaceuticals and chemicals. This interdisciplinary project trains highly talented graduate students and postdoctoral fellows for academic and industrial research in sustainable chemistry, biotechnology, and bioengineering. It is intended to inspire development of new catalyst technologies and methods for enzyme discovery and engineering.This research builds on the principal investigator’s successful engineering of hemeproteins for new-to-nature carbene and nitrene transfer reactions and extends it to discovery and optimization by directed evolution of new enzyme catalysts. These catalysts are used for preparing ring structures that are difficult to make using synthetic chemistry. Intramolecular carbene and nitrene C–H insertion reactions are optimized to access important ring-containing molecules such as lactams, lactones and cyclic amines. In many cases there are no equivalent small-molecule catalysts for these transformations, therefore they will be enabled catalytically for the first time. The utility of the evolved biocatalysts is evaluated in synthesis and late-stage modification of bioactive molecules and precursors to advanced materials. This research also includes kinetic, spectroscopic, structural and computational studies to elucidate the mechanisms of the enzymatic ring-forming reactions and support further enzyme engineering or development of small-molecule catalyst counterparts.This project is co-funded by the Systems and Synthetic Biology cluster in the Division of Molecular and Cellular Biosciences, the Cellular and Biochemical Engineering program in the Division of Chemical, Bioengineering, Environmental, and Transport Systems and the Chemistry of Life Processes program in the Division of Chemistry.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.