Phosphate is an inhibitor of copper-zinc superoxide dismutase.
Phosphate is an inhibitor of copper-zinc superoxide dismutase.
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磷酸盐是铜锌超氧化物歧化酶的抑制剂。
DOI：
10.1021/bi00304a031
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发表时间：
1984
期刊：
影响因子：
2.9
通讯作者：
Valentine,JS
中科院分区：
文献类型：
--
作者：
MotadeFreitas,D;Valentine,JS
Duarte Mota de Freitas和Joan S.情人节 * 摘要：牛铜锌超氧化物歧化酶（Cu，Zn-SOD）在50 mM Hepes [4-（2-羟乙基）-1-哌嗪乙磺酸]（pH7.4）中的超氧化物歧化酶（SOD）活性，在10 mM磷酸盐溶液中，尽管调节两种溶液的离子强度使之相等，但仍下降约50%。用在Arg-141处用苯乙二醛化学修饰的牛Cu，Zn-SOD进行类似的实验，其因此具有未修饰蛋白质的约20%的活性。(This显示活性不是由于残留的未修饰的蛋白质。在修饰蛋白溶液中加入10 mM磷酸盐，SOD活性仅略有下降（< 5%）。磷酸盐的存在也导致了铜，锌-超氧化物歧化酶结合叠氮或氰阴离子的亲和力降低;这种影响的磷酸盐也少得多的甜菜碱修饰的蛋白质。我们的结论是
Duarte Mota de Freitas and Joan S. Valentine* abstract: The superoxide dismutase (SOD) activity of bovine copper-zinc superoxide dismutase (Cu, Zn-SOD) in 50 mM Hepes [4-(2-hydroxyethyl)-l-piperazineethanesulfonic acid], pH 7.4, was decreased by approximately 50% when the solu-tion was made 10 mM in phosphate, in spite of the fact that the ionic strength of both solutions was adjusted to be equal. A similar experiment was carried out with bovine Cu, Zn-SOD chemically modified at Arg-141 with phenylglyoxal, which consequently had approximately 20% of the activity of the unmodified protein.(This activity was shown not to be due to residual unmodified protein.) Addition of 10 mM phosphate to solutions of the modified protein caused only a small de-crease (< 5%) in the SOD activity. The presence of phosphate also caused the affinity ofCu, Zn-SOD for binding azide or cyanide anions to be reduced; this effect of phosphate was also much less for the arginine-modified protein. We conclude that