CRYSTAL-STRUCTURE OF CD,ZN METALLOTHIONEIN
CRYSTAL-STRUCTURE OF CD,ZN METALLOTHIONEIN
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DOI：
10.1126/science.3945804
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发表时间：
1986-02-14
期刊：
影响因子：
56.9
通讯作者：
STOUT, CD
中科院分区：
文献类型：
--
作者：
FUREY, WF;ROBBINS, AH;STOUT, CD
利用天然蛋白质中5种镉的反常散射数据，测定了大鼠肝脏中镉、锌（Cd，Zn）金属硫蛋白异构体II的晶体结构。用直接法求解了4-Cd团簇的结构。A 2.3.角用迭代单波长反常散射计算了高分辨电子密度图。该结构被折叠成两个结构域。氨基末端结构域（β）的残基1至29 enfolds的三金属簇的一个镉和两个锌原子协调的六个终端巯基化半胱氨酸配体和三个桥接巯基化半胱氨酸。羧基末端结构域（α）的残基30至61 enfolds的4-Cd簇由六个终端和五个桥接巯基化半胱氨酸协调。所有七个金属位点具有四面体配位几何结构。畴大致为球形，直径为15至20埃;域之间的联系有限。α的折叠和β拓扑相似但手性相反。冗余的、短的含半胱氨酸序列在α和β中的簇形成中具有相似的作用。和β
The anomalous scattering data from five Cd in the native protein were used to determine the crystal structure of cadmium, zinc (Cd,Zn) metallothionein isoform II from rat liver. The structure of a 4-Cd cluster was solved by direct methods. A 2.3 .ANG. resolution electron density map was calculated by iterative single-wavelength anomalous scattering. The structure is folded into two domains. The amino terminal domain (.beta.) of residues 1 to 29 enfolds a three-metal cluster of one Cd and two Zn atoms coordinated by six terminal cysteine thiolate ligands and three bridging cysteine thiolates. The carboxyl terminal domain (.alpha.) of residues 30 to 61 enfolds a 4-Cd cluster coordinated by six terminal and five bridging cysteine thiolates. All seven metal sites have tetrahedral coordination geometry. The domains are roughly spherical, and the diameter is 15 to 20 .ANG.; there is limited contact between domains. The folding of .alpha. and .beta. is topologically similar but with opposite chirality. Redundant, short cysteine-containing sequences have similar roles in cluster formation in both .alpha. and .beta.