Tyrosine‐Targeted Spin Labeling and EPR Spectroscopy: An Alternative Strategy for Studying Structural Transitions in Proteins

Abstract

Keeping tabs on tyrosine: A three-component Mannich-type reaction extends the scope of site-directed spin labeling by selectively labeling the unique tyrosine residue of CP12 protein (see picture), as was confirmed by mass spectrometry. EPR spectroscopy of the labeled protein showed a very high mobility of the probe, which remained very mobile after complex formation with GAPDH.