Covalent immobilization of mixed proteases, trypsin and chymotrypsin, onto modified polyvinyl chloride microspheres.
Covalent immobilization of mixed proteases, trypsin and chymotrypsin, onto modified polyvinyl chloride microspheres.
复制标题
DOI：
10.1021/jf403476p
复制
发表时间：
2013-10
影响因子：
6.1
通讯作者：
Dong-Fang Li;Hao-Chen Ding;Tao Zhou
中科院分区：
文献类型：
--
作者：
Dong-Fang Li;Hao-Chen Ding;Tao Zhou
将市售的胰蛋白酶-胰凝乳蛋白酶混合物共价固定到改性聚氯乙烯（PVC）微球上，通过随后用乙二胺和戊二醛处理PVC微球来活化PVC微球。采用FT-IR和SEM对固定化混合蛋白酶进行了表征。采用Box-Behnken设计和响应面法对固定化条件进行优化。在最佳条件下（pH6.6，23 °C，2 h）制备的固定化混合蛋白酶活力达到1341 U/g。与游离酶相比，固定化酶具有较高的最适pH值和较宽的pH-活性曲线，上级热稳定性和较高的Km值。固定化混合蛋白酶的重复使用性表明，在重复使用6次后，其活性仍保持在70%以上。
A commercially available trypsin-chymotrypsin mixture was covalently immobilized onto modified polyvinyl chloride (PVC) microspheres, which were activated by the subsequent treatment of PVC microspheres with ethylenediamine and glutaraldehyde. The immobilized mixed protease was characterized by FT-IR and SEM analyses. Immobilization conditions were optimized by Box-Behnken design and the response surface method. The activity of the immobilized mixed protease prepared under optimal conditions (pH 6.6, 23 °C, 2 h) reached 1341 U/g. Compared with the free form, the immobilized enzyme possesses a slightly higher optimal pH value and a wider pH-activity profile, superior thermal stability, and a higher Km value. Reusability of the immobilized mixed protease indicated that >70% of the original activity was retained after having been recycled six times.