Acquotti D, Bonomi F, Brocca P, Ganadu M L, Pagani S
Centro Interuniversitario per lo Studio delle Macromolecule Informazionali, Milano, Italy.
Biochem Biophys Res Commun. 1994 Jul 15;202(1):591-5. doi: 10.1006/bbrc.1994.1969.
Different sets of geminal J coupling constants for the eight beta-CH2 protons in the iron-coordinating cysteines in Clostridium pasteurianum ferredoxin were detected by 2D TOCSY 1H NMR experiments on the oxidized protein. Four resonances were characterized by quite similar high values of J, two more resonances had a J value about half of the former ones, while the last two had extremely low J values. These findings suggest that the cysteines required for cubane symmetry around the iron atoms are constrained into different geometries. The simplified model used for fine tuning of tau m in these TOCSY experiments is also presented and discussed.
通过对氧化态巴氏芽孢杆菌铁氧化还原蛋白中铁配位半胱氨酸的八个β-CH₂质子进行二维全相关谱¹H核磁共振实验，检测到了不同组的偕偶J耦合常数。四个共振峰的特征是具有非常相似的高J值，另外两个共振峰的J值约为前一组的一半，而最后两个共振峰的J值极低。这些发现表明，围绕铁原子形成立方烷对称性所需的半胱氨酸被限制在不同的几何结构中。本文还介绍并讨论了在这些全相关谱实验中用于微调弛豫时间的简化模型。
