Port A E, Hunt D M
Biochem J. 1979 Dec 1;183(3):721-30. doi: 10.1042/bj1830721.
The Cu2+-binding proteins from liver and kidney tissue of 7--8-day-old brindled (Mobr) mice and their normal littermates were compared. (1) Separation over Bio-Gel P-10 showed that the differences in the Cu2+ content of mutant tissues were largely associated with a low-molecular-weight protein fraction (mol.wt. 14 500). (2) Further purification of this low-molecular-weight fraction by anion-exchange chromatography revealed four subfractions. The Cu2+ content of each subfraction reflected the Cu2+ status of the tissue of origin; the Cu2+ contents of the mutant kidney subfractions were elevated and those of the mutant liver were depressed compared with normal. In contrast, the protein contents of the subfractions were less variable and did not reflect the differing Cu2+ contents. (3) Amino acid analysis of the four subfractions from CuCl2-treated mutant and normal animals revealed clos similarities. The proteins showed high glycine, glutamic acid, serine, alanine and lysine contents and a rather variable cysteine content. Differences were apparent in the normal liver subfractions, which showed a higher cysteine content and lower glutamic acid content than did either the mutant liver or normal and mutant kidney subfractions. These observations, together with the recorded presence of aromatic amino acids, indicated that these proteins are not thioneins.
对7 - 8日龄花斑（Mobr）小鼠及其正常同窝仔鼠肝脏和肾脏组织中的铜离子结合蛋白进行了比较。（1）在Bio - Gel P - 10上的分离表明，突变组织中铜离子含量的差异主要与低分子量蛋白组分（分子量14500）有关。（2）通过阴离子交换色谱对该低分子量组分进一步纯化后得到四个亚组分。每个亚组分的铜离子含量反映了其来源组织的铜离子状态；与正常情况相比，突变型肾脏亚组分的铜离子含量升高，而突变型肝脏的铜离子含量降低。相比之下，亚组分的蛋白质含量变化较小，且不能反映不同的铜离子含量。（3）对来自氯化铜处理的突变型和正常动物的四个亚组分进行氨基酸分析，结果显示它们非常相似。这些蛋白质的甘氨酸、谷氨酸、丝氨酸、丙氨酸和赖氨酸含量较高，半胱氨酸含量变化较大。正常肝脏亚组分存在明显差异，其半胱氨酸含量高于突变型肝脏以及正常和突变型肾脏亚组分，而谷氨酸含量则低于这些亚组分。这些观察结果，连同所记录的芳香族氨基酸的存在，表明这些蛋白质不是硫蛋白。
