Mapping Local Protein Electrostatics by EPR of pH-Sensitive Thiol-Specific Nitroxide

• Published in: Biochemistry (Easton) Vol. 47; no. 20; pp. 5626 - 5637
• Main Authors: Voinov, Maxim A, Ruuge, Andres, Reznikov, Vladimir A, Grigor’ev, Igor A, Smirnov, Alex I
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 20.05.2008
• Subjects: Calibration; Electron Spin Resonance Spectroscopy; Hydrogen-Ion Concentration; Nitrogen Oxides - chemistry; Proteins - chemistry; Protons; Sensitivity and Specificity; Static Electricity; Sulfhydryl Compounds - chemistry; Titrimetry

A first thiol-specific pH-sensitive nitroxide spin-label of the imidazolidine series, methanethiosulfonic acid S-(1-oxyl-2,2,3,5,5-pentamethylimidazolidin-4-ylmethyl) ester (IMTSL), has been synthesized and characterized. X-Band (9 GHz) and W-band (94 GHz) EPR spectral parameters of the new spin-lab...