Collaborative Research: Study of A- and B-class dye-decolorizing peroxidases (DyPs): From molecular mechanisms to applications in dye removal and lignin degradation

该奖项将资助堪萨斯州立大学的李平博士和佛罗里达州立大学的宋立凯博士研究A类和B类染料脱色过氧化物酶(DyPs)的分子机制及其结构-性质-活性-功能(SPRF)关系。研究结果可用于废水处理和生物燃料生产的生物催化剂的开发。拟议的研究填补了有关DYPs的关键知识空白，并指导蛋白质工程可能导致酶的氧化活性增强。这一追求使研究生和博士后实习生能够获得从化学到生物等多学科领域的专业知识，从而为他们成为成功的下一代科学家做好准备。还为一项外展计划做出了贡献，该计划鼓励STEM职业生涯中代表性不足的群体的学生主修科学。本研究旨在阐明DYPS这一新的依赖于H_2O_2的血红素过氧化物酶家族的分子机制和SPRF关系。研究主要集中在曲霉热单孢菌的TcDyP和木质素溶解肠杆菌的ElDyP作为该家族A类和B类酶的代表。利用结构生物学、酶学和电子顺磁共振的研究方法，研究了TcDyP中负责底物氧化的酶表面残基、控制涉及ElDyP化合物I的单电子和两电子还原反应的残基(S)以及DyP中围绕血红素口袋的环的动力学。有机合成和蛋白质工程正被用来定义和调节SPRF关系。这项研究的信息不仅填补了DYP的基本知识空白，而且为DYP在染料去除和木质素降解方面的应用铺平了道路。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Ping Li from Kansas State University and Dr. Likai Song from Florida State University to investigate the molecular mechanism of A- and B-class dye-decolorizing peroxidases (DyPs) and their structure-property-reactivity-function (SPRF) relationship. The results of this investigation can be used in the development of biocatalysts for wastewater treatment and biofuel production. The proposed studies fill the critical knowledge gap regarding DyPs and guide protein engineering that could lead to enzymes with enhanced oxidative activity. This pursuit allows the graduate students and postdoctoral trainees to acquire expertise in multidisciplinary areas spanning from Chemistry to Biology, thus preparing them to become successful next-generation scientists. Contributions are also made to an outreach program that encourages students from groups underrepresented in STEM careers to major in science. This research project seeks to elucidate the molecular mechanism and SPRF relationship of DyPs, a new family of H2O2-dependent heme peroxidases. The studies focus on TcDyP from Thermomonospora curvata and ElDyP from Enterobacter lignolyticus as the representatives for the A- and B-class enzymes from this family, respectively. The residues situated on the enzyme surface that are responsible for substrate oxidation in TcDyP, the residue(s) that control one- and two-electron reduction reactions that involve ElDyP compound I, and the dynamics of the loop surrounding the heme pocket in DyPs are being studied using structural biology, enzymology, and electron paramagnetic resonance (EPR) investigation methods. Organic synthesis and protein engineering are being utilized to define and modulate the SPRF relationship. Information from this study not only fills the fundamental knowledge gap on DyPs but also paves the way for DyPs' applications in dye removal and lignin degradation.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.