Munro P A, Dunnill P, Lilly M D
Biotechnol Bioeng. 1977 Jan;19(1):101-24. doi: 10.1002/bit.260190109.
Chymotrypsin has been immobilized to several nonporous magnetic materials. Nickel particles were considered to be most suitable as immobilized enzyme supports. Chymotrypsin immobilized to nonporous magnetic supports was not fouled significantly by either whole milk or clarified yeast homogenate. AE-cellulose-chymotrypsin was rapidly fouled by both these materials and chymotrypsin immobilized to acrylic-based ion exchangers was slowly fouled. Immobilized enzyme activity was found to be inversely proportional to particle diameter for nonporous rock magnetic particles. Immobilization by adsorption and then glutaraldehyde crosslinking was used to produce controlled amounts of chymotrypsin on the particles. Esterolytic activity increased with enzyme loading but caseinolytic activity did not increase. Chymotrypsin is inhibited by metal ions from the magnetic supports. It is partially protected by use of a preliminary protein coating and may be reactivated by incubation with EDTA or BSA.
胰凝乳蛋白酶已被固定在几种无孔磁性材料上。镍颗粒被认为是最适合作为固定化酶载体的材料。固定在无孔磁性载体上的胰凝乳蛋白酶不会被全脂牛奶或澄清的酵母匀浆显著污染。AE-纤维素-胰凝乳蛋白酶会被这两种材料迅速污染，而固定在丙烯酸基离子交换剂上的胰凝乳蛋白酶则会被缓慢污染。对于无孔岩石磁性颗粒，发现固定化酶活性与颗粒直径成反比。通过吸附然后戊二醛交联进行固定，以在颗粒上产生可控量的胰凝乳蛋白酶。酯解活性随酶负载量增加，但酪蛋白分解活性没有增加。胰凝乳蛋白酶受到磁性载体中金属离子的抑制。通过使用初步的蛋白质涂层可对其进行部分保护，并且可通过与EDTA或BSA孵育而重新激活。
