乳酸氧化酶的固定化研究

Immobilization of Lactate Oxidase

将乳酸氧化酶(LOx)在大肠杆菌E.coli BL21(DE3)中重组表达,研究了LOx游离酶的基本性质,优化了LOx的固定化条件,并考察了固定化LOx的使用稳定性及储存稳定性。结果表明,LOx游离酶具有较好的pH值稳定性和热稳定性;LOx的最优固定化条件为:使用ECHA/S氨基载体、LOx游离酶与载体比例为1000∶1(U∶g)、自然盐浓度、固定化温度20℃、固定化pH值7~8;固定化LOx具有较好的使用稳定性和储存稳定性,转化13批次后,固定化LOx酶活无明显下降;4℃下储存130 d,无酶活损失。

Lactate oxidase(LOx)was recombinantly expressed in E.coli BL21(DE3).We studied the basic properties of the free LOx,optimized the immobilization conditions of LOx,and investigated the use stability and storage stability of the immobilized LOx.The results show that the free LOx has good pH value stability and thermal stability.The optimum immobilization conditions of LOx are determined as follows:using ECHA/S amino carrier,the ratio of the free LOx to carrier of 1000∶1(U∶g),natural salt concentration,the immobilization temperature of 20℃,and the immobilization pH value of 7-8.After 13 batches of conversion,the immobilized LOx has no significant decrease in enzyme activity;when stored at 4℃for 130 d,the immobilized LOx shows no loss of enzyme activity,indicating that the immobilized LOx has good use stability and storage stability.