RUI: Novel Heme Chemistry of Cytochrome c'

本研究将研究细胞色素c‘的新血红素化学，细胞色素c’是一种血红蛋白，最近由PI和同事发现，可以将一氧化氮（NO）结合到其近端（而不是远端）血红素面。NO与蛋白质中血红素中心的相互作用在细胞信号传导过程中以及NO水平的调节中是重要的。血红素-一氧化氮近端配位的发现为血红蛋白中的配体结合机制开辟了令人兴奋的新可能性，特别是那些与血红素为基础的一氧化氮传感和一氧化氮毒性保护有关的机制。本提案的科学目标是：(i)研究细胞色素c'中近端血红素- no协调的化学后果；（ii）了解为什么NO与近端（而不是远端）血红素面结合；（iii）了解细胞色素c‘如何调节其与NO的反应性，以及（iv）研究细胞色素c’帮助降低溶液中游离NO水平的可能机制。利用紫外可见吸收、共振拉曼光谱、闪光光解和停流动力学等技术研究细胞色素c的血红素化学。重组细胞色素c'蛋白将用于研究氨基酸替代对血红素反应性的影响。该项目的广泛影响包括为东俄勒冈大学的本科生提供从事前沿研究的机会。由于这个项目的合作性质，学生将在不同的实验室环境中获得各种生物化学和生物物理技术的实践经验，这将增加他们的学术研究，并为未来的科学努力提供宝贵的技能。该项目将延续PI部门支持和促进本科生研究的传统，并将为该机构目前生物化学教育和研究的转型增添动力。此外，该项目将使PI能够在课堂和研究社区中保持智力活力。

This research at an undergraduate institution (RUI) will investigate the novel heme chemistry of cytochrome c', a hemoprotein recently shown by the PI and coworkers to bind nitric oxide (NO) to its proximal (rather than distal) heme face. The interaction of NO with heme centers in proteins is important in cellular signaling processes, as well as in the regulation of NO-levels. The discovery of a proximal heme-NO coordination opens up exciting new possibilities for ligand binding mechanisms in hemoproteins, particularly those connected with heme-based NO-sensing and protection against NO toxicity. The scientific objectives of this proposal are (i) to investigate the chemical ramifications of proximal heme-NO coordination in cytochrome c'; (ii) to understand why NO binds to the proximal (rather than distal) heme face; (iii) to understand how cytochrome c' modulates its reactivity with NO, and (iv) to investigate possible mechanisms by which cytochrome c' could help reduce the levels of free NO in solution. The heme chemistry of cytochrome c' will be studied using the techniques of UV-visible absorption, resonance Raman spectroscopy, flash-photolysis, and stopped-flow kinetics. Recombinant cytochrome c' proteins will be used to study the effect of amino acid replacements on heme reactivity. The broader impacts of this project include opportunities for undergraduate students at Eastern Oregon University to be engaged in cutting-edge research. Due to the collaborative nature of this project, students will gain hands-on experience in a variety of biochemical and biophysical techniques in different laboratory environments, which will augment their academic studies and provide valuable skills for future scientific endeavors. The project will continue the tradition of the PI's department in supporting and promoting undergraduate research, and will add momentum to the current transformation of biochemistry education and research at this institution. Moreover, the project will enable the PI to maintain intellectual vibrancy within the classroom and research community.