Purification and characterisation of glyoxalase II from human red blood cells.
Purification and characterisation of glyoxalase II from human red blood cells.
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从人红细胞中纯化和表征乙二醛酶 II。
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
Paul J Thornalley
中科院分区：
文献类型：
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作者：
R. E. Allen;T. W. Lo;Paul J Thornalley
从人红细胞中纯化出乙二醛酶II。纯化因子为83，300，产率为24%或1.7微克/ml红细胞。纯化的蛋白质是分子量为29，200 Da、等电点为8.3的单体。由谷胱甘肽酶II催化的S-D-乳酰谷胱甘肽水解为还原型谷胱甘肽和D-乳酸盐的速率遵循Michaelis-Menten动力学，其中在37 ℃下，在50 mM Tris/HCl，pH 7.4中，Km和kcat值分别为146 +/- 9 μ M和727 +/- 16 s-1。其他S-2-羟酰基谷胱甘肽衍生物也是可接受的底物。S-p-硝基苄氧羰基谷胱甘肽是谷胱甘肽酶II的强竞争性抑制剂，Ki值为1.20 +/- 0.21 μ M，而甲基乙二醛与还原型谷胱甘肽反应非酶促形成的半硫缩醛是弱竞争性抑制剂，Ki值为834 +/- 98 μ M。
Glyoxalase II was purified from human red blood cells. The purification factor was 83,300 and the yield was 24% or 1.7 micrograms/ml red blood cells. The purified protein was a monomer with a molecular mass of 29,200 Da and an isoelectric point of 8.3. The rate of hydrolysis of S-D-lactoylglutathione to reduced glutathione and D-lactate, catalysed by glyoxalase II, followed Michaelis-Menten kinetics where the Km and kcat values were 146 +/- 9 microM and 727 +/- 16 s-1, respectively in 50 mM Tris/HCl, pH 7.4 at 37 degrees C. Other S-2-hydroxyacylglutathione derivatives were also acceptable substrates. S-p-Nitrobenzoxycarbonylglutathione was a potent competitive inhibitor of glyoxalase II with a Ki value of 1.20 +/- 0.21 microM, and the hemithioacetal formed non-enzymically from the reaction of methylglyoxal with reduced glutathione was a weak competitive inhibitor with a Ki value of 834 +/- 98 microM.