大孔树脂固定化磷脂酶D

Immobilization of phospholipase D by macroporous resin

磷脂酶D(Phospholipase D,EC3.1.4.4,PLD)是催化磷酸酯键水解和碱基交换反应的一类酶的总称。利用PLD的转碱基作用是目前催化合成磷脂酰丝氨酸(PS)的最佳途径。本实验以5种大孔树脂为载体固定化磷脂酶D(PLD)进行了研究。以酶回收率为主要指标,选择了最佳载体和优化了固定化条件。结果表明:非极性阳离子交换树脂H103是最佳固定化载体;其最优固定化条件:加酶液量1.2 m L,固定时间80 min,p H 6.0柠檬酸-柠檬酸钠的缓冲液浓度为10 mmol/L。最佳固定化条件下,固定化之后的PLD比游离PLD酶活提高了三倍。

Phospholipase D （PLD） generally defined as a kind of enzyme catalyzes PC to generate choline and PA. PLD transacylation is currently the best way for catalytic synthesis of phosphatidylserine. In this study, five kinds of macroporous resin were chosen to immobilize phospholipase D. The enzyme recovery activity was served as the main indexes, then the optimum carrier was confirmed and the immobilized conditions were optimized. The results showed that the nonpolar H103 was the best carrier and the optimum conditions for immobilized PLD were as follows： the amount of enzyme solution 1.2 mL, pH 6.0 of citric acid-sodium citrate buffer 10 mmol/L and immobilized for 80 minutes. Under the optimized conditions, the immobilized PLD displayed the highest activity, which was three times than that of the free PLD.