Hinberg I, O'Driscoll K F
Biotechnol Bioeng. 1975 Oct;17(10):1435-41. doi: 10.1002/bit.260171004.
Urate oxidase from hog liver (urate: oxygen oxidoreductase, EC 1.7.33) has been entrapped in a crosslinked 2-hydroxyethyl methacrylate gel with a 47% retention of activity. The kinetic behavior of the gel entrapped enzyme has been studied in a slurried tank reactor using uric acid as substrate. Internal diffusion effects were found to be negligible for particle sizes below 128 mum. A threefold increase in Km (app) was observed for the 128 mum particles and attributed to diffusional effects. The pH activity profile of the gel entrapped enzyme was bell-shaped at high substrate concentration and could be fitted to a titration curve of two ionizable groups, a basic group having a pK of 7.9 and an acidic group with a pK of 11.0. The gel entrapped enzyme showed excellent stability between pH 6.5 and 10.5.
猪肝尿酸氧化酶（尿酸：氧氧化还原酶，EC 1.7.33）被包埋在交联的甲基丙烯酸2-羟乙酯凝胶中，活性保留率为47%。在搅拌釜式反应器中，以尿酸为底物，研究了凝胶包埋酶的动力学行为。发现粒径小于128μm时，内部扩散效应可忽略不计。对于128μm的颗粒，观察到Km（表观）增加了三倍，这归因于扩散效应。在高底物浓度下，凝胶包埋酶的pH活性曲线呈钟形，可拟合为两个可电离基团的滴定曲线，一个碱性基团的pK为7.9，一个酸性基团的pK为11.0。凝胶包埋酶在pH 6.5至10.5之间表现出优异的稳定性。
