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

从药物到塑料，环状结构的分子无处不在，它们的特殊结构赋予了它们重要的功能特性。发现和开发此类分子和材料的瓶颈往往是用简单的起始材料构建复杂环的能力有限。这个项目建立了强大的和可推广的酶的途径，以不同的环结构，使用化学以前不知道在生物催化。这种新自然界的环状形成酶完全是遗传编码的，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、药品和化学品。该跨学科项目为可持续化学、生物技术和生物工程的学术和工业研究培养高素质的研究生和博士后。它的目的是激发新的催化剂技术和方法的发展，酶的发现和工程。这项研究建立在首席研究员成功的血红蛋白工程上，用于新的自然碳和亚硝基转移反应，并通过定向进化将其扩展到发现和优化新的酶催化剂。这些催化剂用于制备难以用合成化学方法制备的环状结构。优化了分子内羰基和亚硝基C-H插入反应，以接近重要的含环分子，如内酰胺、内酯和环胺。在许多情况下，没有等效的小分子催化剂来进行这些转化，因此它们将首次在催化上实现。生物催化剂在生物活性分子和先进材料前体的合成和后期修饰中的应用进行了评价。本研究还包括动力学、光谱、结构和计算研究，以阐明酶环形成反应的机制，并为进一步的酶工程或小分子催化剂的开发提供支持。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、环境和运输系统部门的细胞和生化工程项目以及化学部门的生命过程化学项目共同资助。该奖项反映了美国国家科学基金会的法定使命，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.