Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland.
J Phys Chem B. 2013 Mar 21;117(11):3145-53. doi: 10.1021/jp401806g. Epub 2013 Mar 8.
We present the first example of chemoselective site-specific spin labeling of a monomeric protein with two spectroscopically orthogonal spin labels: a gadolinium(III) chelate complex and a nitroxide radical. A detailed analysis of the performance of two commercially available Gd(III) ligands in the Gd(III)-nitroxide pulse double electron-electron resonance (DEER or PELDOR) experiment is reported. A modification of the flip angle of the pump pulse in the Gd(III)-nitroxide DEER experiment is proposed to optimize sensitivity.
镧系金属螯合物复合物和氮氧自由基，对单体蛋白进行化学选择性定点自旋标记的实例。详细分析了两种市售的 Gd(III)配体在 Gd(III)-氮氧自由基脉冲双电子-电子共振（DEER 或 PELDOR）实验中的性能。提出了在 Gd(III)-氮氧自由基 DEER 实验中改变泵浦脉冲翻转角以优化灵敏度的方法。
