Roles of metallothionein and related proteins in metal metabolism and toxicity: problems and perspectives.
Roles of metallothionein and related proteins in metal metabolism and toxicity: problems and perspectives.
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DOI：
10.1289/ehp.8665217
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发表时间：
1986-03
影响因子：
10.4
通讯作者：
Fowler BA
中科院分区：
文献类型：
--
作者：
Petering DH;Fowler BA
本文从化学角度考察了金属硫蛋白及其相关蛋白在调节金属代谢和毒性方面的一些已知和假想的作用。它试图从动力学的角度研究这些分子如何对基本的酶或其他分子系统中金属离子的细胞内生物有效性施加动态平衡控制。金属硫蛋白和相关蛋白质与细胞内其他金属结合部位之间持续竞争的概念也与这些蛋白质的热力学稳定性有关。哺乳动物金属硫蛋白与非哺乳动物类似蛋白的比较表明，它们在金属结合部位的类型、金属结合常数、氨基酸组成和二级结构上既有相似之处，又有很大的差异，使得自然界中这些低分子量金属结合分子的表观多样性似乎越来越大。这些数据的潜在价值在于描绘了金属硫蛋白进化的新假说，并为发现细胞中金属硫蛋白及其相关蛋白的正常功能提供了新的模型系统。
This summary examines some of the known and hypothesized roles of metallothionein and related proteins in mediating the metal metabolism and toxicity from a chemical perspective. It attempts to examine in kinetic terms how such molecules may exert homeostatic control over the intracellular bioavailability of metal ions to essential enzymatic or other molecular systems. The concept of ongoing competition between metallothionein and related proteins with other intracellular metal-binding sites for various metals is also examined in relation to the thermodynamic stability of these proteins. Comparisons between mammalian metallothionein and analogous nonmammalian proteins demonstrate both similarities and great differences in types of metal-binding sites, metal-binding constants, amino acid composition, and secondary structures such that apparent diversity of these low molecular weight metal-binding molecules in nature appears to be growing ever wider. The potential value of these data rests both in delineating new hypotheses for metallothionein evolution and in suggesting new model systems for discovering the normal function of metallothionein and related proteins in cells.