RUI: Novel Heme Chemistry of Cytochrome c'

Eastern Oregon University, La Grande OR

Investigators

Abstract

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.