Gutensohn W, Jahn H
Eur J Clin Invest. 1979 Feb;9(1):43-7. doi: 10.1111/j.1365-2362.1979.tb01665.x.
A mutant hypoxanthine-phosphoribosyltransferase (EC 2.4.2.8.) from a patient with gout is examined. The activity of the erythrocyte enzyme is about 5% of normal in this case. Immunoprecipitation studies using antiserum against highly purified human hypoxanthine-phosphoribosyltransferase reveal that the patient's erythrocytes contain a normal amount of cross-reacting material. The mutant enzyme has an altered net charge as shown by preparative isoelectric focusing (pI values of 5.75 and 4.55). The influence of chemical modification on enzymic activity was studied using a number of different reagents directed against sulfhydryl-, amino-, and guanidino-groups. Compared with normal hypoxanthine-phosphoribosyltransferase the mutant enzyme shows a generally lowered susceptibility to active site-directed inhibition. It is concluded that the patient's enzyme is the product of a structural mutation.
对一名痛风患者的突变次黄嘌呤 - 磷酸核糖转移酶（EC 2.4.2.8.）进行了检测。在这种情况下，红细胞酶的活性约为正常水平的5%。使用针对高度纯化的人次黄嘌呤 - 磷酸核糖转移酶的抗血清进行免疫沉淀研究表明，患者的红细胞含有正常量的交叉反应物质。如制备性等电聚焦所示（pI值为5.75和4.55），突变酶的净电荷发生了改变。使用多种针对巯基、氨基和胍基的不同试剂研究了化学修饰对酶活性的影响。与正常次黄嘌呤 - 磷酸核糖转移酶相比，突变酶对活性位点定向抑制的敏感性普遍降低。得出的结论是，患者的酶是结构突变的产物。
