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金属蛋白由于其所带金属离子具有未配对电子而具有顺磁性，致使弛豫时间缩短、谱线加宽（～５０Ｈｚ）以及谱范围变大（～１００ｐｐｍ），因而具有与抗磁蛋白不同的谱特征。这时一些常用的２ＤＮＭＲ实验方法将失效。本文探索顺磁金属蛋白的几种ＮＭＲ实验方法，如溶剂峰抑制、２ＤＭＣＯＳＹ、ＮＯＥＳＹ、１ＤＮＯＥ差谱及ＳＵＰＥＲＷＥＦＴ等，并精心设计实验条件使之适用于顺磁金属蛋白的结构研究。这些实验方法成功地应用于紫色震颤菌血红蛋白（ｍｅｔ－ＶｔＨｂ－ＣＮ）。通过这些实验找到了与血红素Ｆｅ３＋配位的组氨酸，并完成了该金属蛋白的顺磁位移的共振峰的识别、活性中心质子间距离的测量、抗磁性化学位移及电离常数ｐＫａ值的确定。
Metalloproteins have paramagnetic properties due to their metal ions having unpaired electrons, resulting in shorter relaxation times, broadened spectral lines (-50 Hz), and larger spectral ranges (-100 ppm), thus having a different spectrum from diamagnetic proteins feature. At this point some of the commonly used 2D NMR experimental methods will fail. This paper explores some NMR experimental methods of paramagnetic metal proteins, such as solvent peak suppression, 2DMCOSY, NOESY, 1DNOE difference spectra and SUPERWEFT, and carefully designed experimental conditions to make them suitable for the structural study of paramagnetic metal proteins. These experimental methods were successfully applied to purple-vibrio hemoglobin (met-VtHb-CN). Through these experiments, the histidine coordinated to heme Fe3 + was found and the formant of the paramagnetic shift of the metalloprotein was identified. The distance between active proton protons, the diamagnetic chemical shift and the pKa value of the ionization constant determine.