title: How protein structure affects redox reactivity: example of Human centrin 2.
abstract: Electron transfer inside proteins plays a central role in their reactivity and biological functions. Herein, we developed a combined approach by gamma radiolysis and electrochemistry which allowed a deep insight into the reactivity of Human centrin 2, a protein very sensitive to oxidative stress and involved in several key biological processes. This protein bears a single terminal tyrosine and was observed to be extremely sensitive to ionizing radiation sources, leading to a tyrosine dimer. By cyclic voltammetry in the 100-1000 V s(-1) range, its redox potential and dimerization rate could be evaluated. Accordingly, reaction in solution with a redox mediator revealed an efficient catalysis. Finally, protein denaturation by a progressive increase in temperature was proportional to a decrease of dimerization radiolytic yield. Our results thus demonstrated that the protein structure plays a major role in oxidation sensitivity. This leads to meaningful results to understand protein redox reactivity.
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, UMR 8235, Laboratoire Interfaces et Systèmes Electrochimiques, F-75005, Paris, France. emmanuel.maisonhaute@upmc.fr.
authors.forename: Abdeslam
authors.initials: A
authors.lastname: Et Taouil
authors.forename: Emilie
authors.initials: E
authors.lastname: Brun
authors.forename: Patricia
authors.initials: P
authors.lastname: Duchambon
authors.forename: Yves
authors.initials: Y
authors.lastname: Blouquit
authors.forename: Manon
authors.initials: M
authors.lastname: Gilles
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Maisonhaute
authors.forename: Cécile
authors.initials: C
authors.lastname: Sicard-Roselli
mesh_terms: D002135:Calcium-Binding Proteins / Q000737:chemistry*; D002384:Catalysis; D018797:Cell Cycle Proteins / Q000737:chemistry*; D055664:Electrochemical Techniques; D004579:Electron Transport; D005720:Gamma Rays; D006801:Humans; D008958:Models, Molecular; D010084:Oxidation-Reduction; D011487:Protein Conformation / Q000528:radiation effects; D014443:Tyrosine / Q000737:chemistry*
chemical_list: C472752:CETN2 protein, human; D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; D014443:Tyrosine