Remaining structures at the N- and C-terminal regions of alpha-synuclein accurately elucidated by amide-proton exchange NMR with fitting

AbstractAlpha-synuclein is analyzed in physiological conditions by CLEANEX-PM methodology, in which the amide-proton exchange can be monitored at millisecond scale. The relationship between kex and [OH]− is confirmed as a linear correlation with slope 1, indicating EX2 regime. There are significant residual structures at the N- and C-terminal regions. The structure at the C-terminal region is more stable than that of the N-terminal region. The middle part including NAC region is not completely protected. The data acquired at various pH and mixing time conditions followed by linear fitting give accurate information about residual structures

Activity Enhancement of a Carbon Electrode Material for Vanadium Redox Flow Battery by Electron-Beam Irradiation

The effective addition of surface oxygen groups, which are active sites for redox reactions, on carbon clothes as electrodes by electron beam irradiation in normal air which contains environmental humidity, dry air, or nitrogen atmosphere was carried out. The irradiation introduced 20 at% oxygen at the carbon surface as determined by X-ray photoelectron spectroscopy and the phenol-type hydroxyl group, the carboxylic group, etc., were detected by temperature-programmed desorption. Single-cell measurements indicated the current density at 1.3 V-IR-corrected of the irradiated electrode in normal air was 28% higher than that of the as-received electrode. Since double-layer capacitance between the as-received carbon cloth and irradiated carbon cloth in normal air was similar, the improvement of current density is attributed to the increase of surface oxygen groups. In addition, the radiation in both normal air and dry air improved electrochemical activity similarly. This result suggests the radiation-chemical reaction in this study is dominated by the oxidation reaction with ozone or nitrogen oxides (NOx), while in the meantime, the contribution of the hydroxyl radical from water is considered to be negligible