离子液体修饰碳复合材料固定化脱氢酶  

Immobilization of dehydrogenases byionic liquid modified carbon composite materials

作　　者：刘凯泷 张骞 江亮 王世珍[1] LIU Kailong;ZHANG Qian;JIANG Liang;WANG Shizhen(College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China)

机构地区：[1]厦门大学化学化工学院,福建厦门361005

出　　处：《生物加工过程》2023年第3期255-262,共8页Chinese Journal of Bioprocess Engineering

基　　金：国家自然科学基金面上项目(21776233、22078273);福建省自然科学基金面上项目(2018J01013);中央高校基本科研业务费专项资金(20720200038、20720170033)。

摘　　要：为了探究离子液体修饰的氧化石墨烯聚乙烯亚胺(GO PEI)材料对苯丙氨酸脱氢酶固定化的影响,首先采用不同咪唑基离子液体对游离苯丙氨酸脱氢酶进行修饰,其次利用咪唑基离子液体[BMIM]Cl修饰GO PEI,分别考察GO、GO PEI和GO PEI[BMIM]Cl固定化苯丙氨酸脱氢酶的性能,然后利用扫描电镜(SEM)以及红外光探究酶固定化的机制。结果表明:咪唑基离子液体中[BMIM]Cl对酶有激活作用,其相对酶活为110.0%;GO PEI PheDH[BMIM]Cl固定化酶的酶活可达93.5%,高于GO PheDH和GO PEI PheDH固定化酶,且温度耐受性和pH耐受性均比游离酶有所提高;GO PEI PheDH[BMIM]Cl固定化酶经过6次重复利用,仍可保持82.7%的酶活,而对照的GO PEI固定化酶的酶活为69.7%。离子液体修饰的碳复合材料具有良好的生物相容性和导电性,在非水相酶催化和生物电催化领域具有广阔的应用前景。Ionic liquids functionalized polyethyleneimine-modified graphene oxide(GO-PEI)was applied in the immobilization of phenylalanine dehydrogenase(PheDH).As three imidazolidine ionic liquids showed different impact on the enzymatic activity of free phenylalanine dehydrogenase,the best-performing ionic liquid[BMIM]Cl was selected for the modification of GO-PEI,and the immobilization mechanism was studied by morphology characterization by SEM and infrared analysis.Our major observations include the following several points:a)[BMIM]Cl could enhance the enzymatic activity by 1.1-fold.b)By comparison of the catalytic characteristic of PheDH immobilized by GO,GO-PEI,GO-PEI-[BMIM]Cl,the activity recovery for GO-PEI-PheDH-[BMIM]Cl was 93.5%,which was higher than those for GO-PheDH and GO-PEI-PheDH.c)Immobilization could improve the stability of enzyme PheDH,resulting in higher optimal temperature and pH.In addition,the enzymatic activity of GO-PEI-PheDH-[BMIM]Cl maintained at the level of 82.7%after reuse for 6 times,while GO-PEI-PheDH could only retain the activity at 69.7%.Due to the synergistic effect from good biocompatibility and conductivity,ionic liquid modified carbon composites have great potential for enzyme immobilization,especially in the field ofbioelectrocatalysis.

关 键 词：生物催化 酶 复合材料 离子液体 非水相体系 

分 类 号：Q814.2[生物学—生物工程]