How protein structure affects redox reactivity: example of Human centrin 2

作者：Taouil Abdeslam Et; Brun Emilie; Duchambon Patricia; Blouquit Yves; Gilles Manon; Maisonhaute Emmanuel^*; Sicard Roselli Cecile

来源：Physical Chemistry Chemical Physics, 2014, 16(44): 24493-24498.

DOI：10.1039/c4cp03536d

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.

• 出版日期2014