Kulshrestha Yasha, Husain Qayyum
Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, UP, India.
Biomol Eng. 2006 Dec;23(6):291-7. doi: 10.1016/j.bioeng.2006.07.004. Epub 2006 Aug 1.
This study demonstrates the immobilization of carbohydrate containing turnip peroxidase on an inexpensive bioaffinity adsorbent, Concanavalin A-cellulose support. The bioaffinity support was prepared simply by incubating cellulose powder with jack bean extract at 4 degrees C. Cellulose powder adsorbed 30 mg concanavalin A/g of the matrix. Concanavalin A adsorbed cellulose has been employed for the simultaneous purification and immobilization of glycoenzymes directly from ammonium sulphate fractionated proteins of turnip. The obtained bioaffinity support was quite effective in high yield immobilization of peroxidase from turnip and it retained 672 U/g. Turnip peroxidase immobilized on concanavalin A-cellulose support retained 80% of the initial activity. Immobilized turnip peroxidase preparation was quite resistant against the denaturation mediated by pH, heat, urea, guanidinium-HCl, Surf Excel, cetyltrimethylammonium bromide and water-miscible organic solvents; dimethyl formamide, dioxane and n-propanol. Low concentration of detergents like Surf Excel and cetyltrimethylammonium bromide enhanced the activity of soluble and immobilized turnip peroxidase.
本研究展示了将含碳水化合物的萝卜过氧化物酶固定在一种廉价的生物亲和吸附剂——伴刀豆球蛋白A-纤维素载体上。这种生物亲和载体的制备很简单,只需在4℃下将纤维素粉末与刀豆提取物孵育即可。纤维素粉末每克基质吸附30毫克伴刀豆球蛋白A。吸附了伴刀豆球蛋白A的纤维素已被用于直接从萝卜硫酸铵分级分离的蛋白质中同时纯化和固定糖酶。所获得的生物亲和载体在高产率固定萝卜过氧化物酶方面相当有效,其保留活性为672 U/g。固定在伴刀豆球蛋白A-纤维素载体上的萝卜过氧化物酶保留了初始活性的80%。固定化的萝卜过氧化物酶制剂对由pH、热、尿素、盐酸胍、汰渍洗衣粉、十六烷基三甲基溴化铵和与水混溶的有机溶剂(二甲基甲酰胺、二氧六环和正丙醇)介导的变性具有相当的抗性。低浓度的洗涤剂如汰渍洗衣粉和十六烷基三甲基溴化铵可提高可溶性和固定化萝卜过氧化物酶的活性。