New Catalysts by Cofactor Modulation

辅因子调节的新催化剂

• 批准号: 2204096
• 负责人: Steven Rokita
• 金额: $ 51万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2204096&HistoricalAwards=false
• 关键词: New; Catalysts; Cofactor; Modulation

With the support of the Chemistry of Life Processes (CLP) program in the Division of Chemistry, Professor Steven Rokita from Johns Hopkins University is studying the development of new catalysts based on proteins containing synthetic analogues of natural cofactors. Complexes between proteins and their cofactors are highly efficient at promoting reactions that are fundamental to our own metabolism. However, their exquisite specificity precludes their widespread application for industry. Proteins can often be engineered to enhance their catalytic repertoire for such applications. Cofactor engineering offers a powerful alternative to protein engineering but has received little attention to date. This project will use organic chemistry to synthesize new cofactors that, in combination with their protein scaffolds, may be applied to green chemistry and bioremediation. The project will provide advanced training, spanning chemistry and biochemistry, and will provide students with a foundation for future contributions to enzyme optimization and application in biocatalytic process chemistry, an emerging area in sustainable chemistry. The power of chemistry to manipulate biological systems will also be introduced into new courses associated with the creation of a biochemistry major through a collaboration between the Departments of Chemistry, Biophysics, and Biology at Johns Hopkins University. Enzymes of the flavin-dependent nitroreductase superfamily promote a wide range of chemical transformations with promise for deployment in industrial biocatalytic processes. Still, the search for natural variants and the construction of enzyme libraries has yet to produce satisfactory candidates from the best characterized subgroups of nitroreductases and iodotyrosine deiodinases. Under this project, research in the Rokita laboratory will instead focus on controlling specificity and chemistry by modifying the cofactors necessary to promote catalysis. Only minor changes to the flavin structure can engender large changes in catalytic chemistry as illustrated by examples of 5-deazaflavin and 6-carboxyflavin. The reducing power of native flavin is not sufficient to drive the full reduction of nitroaromatics to their amine products, but a nitroreductase containing 5-deazaflavin should have sufficient reducing capacity to produce the amines, for example. In a complementary aim, the ability of 6-carboxyflavin to form a more stable semiquinone intermediate than the native cofactor will be integrated into biocatalyst development for reductive dehalogenation 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.

在化学系生命过程化学（CLP）项目的支持下，约翰霍普金斯大学的Steven Rokita教授正在研究基于含有天然辅因子合成类似物的蛋白质的新催化剂的开发。 蛋白质及其辅因子之间的复合物在促进对我们自身代谢至关重要的反应方面非常有效。 然而，它们精致的特异性排除了它们在工业上的广泛应用。 蛋白质通常可以被工程化以增强其用于此类应用的催化库。 辅因子工程为蛋白质工程提供了一种强有力的替代方案，但迄今为止很少受到关注。 本项目将利用有机化学合成新的辅因子，与它们的蛋白质支架结合，可能应用于绿色化学和生物修复。 该项目将提供先进的培训，跨越化学和生物化学，并将为学生提供酶优化和生物催化过程化学应用的未来贡献的基础，这是可持续化学的一个新兴领域。 化学操纵生物系统的力量也将被引入到与生物化学专业的创建相关的新课程中，通过约翰霍普金斯大学化学，生物物理学和生物学系之间的合作。黄素依赖性硝基还原酶超家族的酶促进广泛的化学转化，有望在工业生物催化过程中部署。尽管如此，寻找天然变体和构建酶库还没有产生令人满意的候选人从硝基还原酶和碘酪氨酸脱碘酶的最佳特征的亚组。 在该项目下，Rokita实验室的研究将集中在通过修改促进催化所需的辅因子来控制特异性和化学。 仅对黄素结构的微小改变可引起催化化学的大的改变，如5-脱氮黄素和6-羧基黄素的实例所示。 天然黄素的还原能力不足以驱动硝基芳族化合物完全还原为它们的胺产物，但是含有5-脱氮黄素的硝基还原酶应该具有足够的还原能力来产生例如胺。 在一个互补的目标中，6-羧基黄素形成比天然辅因子更稳定的半醌中间体的能力将被整合到还原脱卤化学的生物催化剂开发中。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。