Arroyo-Begovich A, DeMoss J A
Proc Natl Acad Sci U S A. 1969 Nov;64(3):1072-8. doi: 10.1073/pnas.64.3.1072.
A multienzyme complex that catalyzes the anthranilate synthetase, phosphoribosylanthranilate (PRA) isomerase, and indoleglycerolphosphate (InGP) synthetase reactions was produced in vitro when extracts from a tryp-1 mutant and a tryp-2 mutant of Neurospora crassa were mixed. The sedimentation values and the molecular weights for the interacting components obtained from the mutants were estimated by sucrose gradients and by gel filtration on Sephadex columns. The component coded for by the tryp-2 gene (a-component) which is present in the tryp-1-17 mutant has a sedimentation coefficient of 4.5S and molecular weight of 70,000. The component coded for by the tryp-1 gene (i-component) which is present in the tryp-2-6 mutant has a sedimentation coefficient 7.5S and a molecular weight of 170,000. The complex formed in vitro had similar properties to those previously reported for the wild-type complex. A Q(10) value of 3 and an apparent activation energy of 18,000 cal/mole were calculated for the formation of the complex from the two components.
当将粗糙脉孢菌的tryp - 1突变体和tryp - 2突变体的提取物混合时，在体外产生了一种多酶复合物，该复合物催化邻氨基苯甲酸合成酶、磷酸核糖基邻氨基苯甲酸（PRA）异构酶和吲哚甘油磷酸（InGP）合成酶反应。通过蔗糖梯度和在Sephadex柱上进行凝胶过滤，对从突变体中获得的相互作用组分的沉降值和分子量进行了估计。tryp - 1 - 17突变体中存在的由tryp - 2基因编码的组分（a组分）的沉降系数为4.5S，分子量为70,000。tryp - 2 - 6突变体中存在的由tryp - 1基因编码的组分（i组分）的沉降系数为7.5S，分子量为170,000。体外形成的复合物具有与先前报道的野生型复合物相似的性质。由这两种组分形成复合物的Q(10)值为3，表观活化能为18,000卡/摩尔。
