Abrahams I L, Bremner I, Diakun G P, Garner C D, Hasnain S S, Ross I, Vasák M
Biochem J. 1986 Jun 1;236(2):585-9. doi: 10.1042/bj2360585.
Zn-metallothionein 1 from rabbit liver was investigated by means of Zn K-edge extended X-ray-absorption fine structure (e.x.a.f.s.). Also, the Cu and Zn K-edge e.x.a.f.s. were measured for two samples of mixed Cu Zn-metallothionein 2, with Cu/Zn ratios of 5:2 and 6:3, from pig liver. Detailed simulation of the Cu sites shows a primary co-ordination with three sulphur atoms, presumably from cysteine residues at 0.225 nm +/- 0.001 nm (2.25 +/- 0.01 A). The data for the Zn sites are best reproduced by four Zn-S separations at 0.233 +/- 0.001 nm (2.33 +/- 0.01 A). The Zn K-edge e.x.a.f.s. recorded for rabbit metallothionein 1 at 77 K shows, in addition to the primary co-ordination shell, evidence for two Zn-Zn separations at approx. 0.50 nm (5.0 A). This latter result provides the first information concerning the internal arrangement of zinc atoms in Zn7-metallothionein.
采用锌K边扩展X射线吸收精细结构(e.x.a.f.s.)对兔肝中的锌金属硫蛋白1进行了研究。此外,还对猪肝中两种铜锌比分别为5:2和6:3的混合铜锌金属硫蛋白2样品进行了铜和锌K边e.x.a.f.s.测量。对铜位点的详细模拟显示,主要与三个硫原子配位,推测这些硫原子来自半胱氨酸残基,距离为0.225 nm±0.001 nm(2.25±0.01 Å)。锌位点的数据通过四个0.233±0.001 nm(2.33±0.01 Å)的锌-硫间距能得到最佳重现。在77 K下记录的兔金属硫蛋白1的锌K边e.x.a.f.s.显示,除了主要配位层外,还存在两个约0.50 nm(5.0 Å) 的锌-锌间距的证据。后一结果提供了关于Zn7-金属硫蛋白中锌原子内部排列的首个信息。