新型D-氨基酰化酶的特性及固定化酶的研究  

A Study on the Characterization of a Novel D-aminoacylase and Immobilized Enzyme

作　　者：刘建[1] 李明堂[1] 李洪广[1] 孙立志[1] 

机构地区：[1]长春理工大学生命科学技术学院,长春130022

出　　处：《长春理工大学学报（自然科学版）》2015年第2期142-146,共5页Journal of Changchun University of Science and Technology(Natural Science Edition)

基　　金：吉林省科技厅资助项目(20100950)

摘　　要：本文研究了一株具有N-酰基酰化酶(DAA)生产能力的细菌,通过对其酶学特性及固定化酶用于D-氨基酸的生产进行了研究。显示此酶的最适温度为37℃,最适p H7.4,1mmol/L以下的Ca Cl2,Cd Cl2,Co Cl2,Cu Cl2,Fe Cl2,Hg Cl2,Mn Cl2,Zn Cl2对酶的活性没有影响,在20mmol/L的EDTA条件下仍可保持65%的酶活性。底物特异性显示酶的最佳底物是N-乙酰-D-苯丙氨酸,50mmol/L以上的N-乙酰-D-苯丙氨酸显著抑制酶的活性。利用海藻酸钠固定酶后,在30℃条件下,使用50mmol/L的N-酰基-D-苯丙氨酸底物进行的降解实验显示水解率可以达到84%,转化批次达到6次以上,活性保持达到70小时以上。This paper analyzes a bacterium possessing the capacity to produce D-aminoacylase （DAA） and its applica-tion in the production of D-amino acid by analyzing its characterization of enzyme and immobilized enzyme. The results show that the optimum temperature of the enzyme is 37℃,the optimum pH is 7.4. Moreover, CaCl2, CdCl2, CoCl2, CuCl2, FeCl2, HgCl2, MnCl2, ZnCl2 under 1mmol/L have no effect on the enzyme activity, it can maintain 65% en-zyme activity under the EDTA condition of 20mmol/L. The substrate specificity shows that the optimum substrate is N-acetyl-D-phenylalanine.N-acetyl-D-phenylalanine above 50mmol/L inhibits the enzyme activity remarkably. Under the condition of 30℃, making use of immobilized DAA of sodium alginate, the degradation experiment using N-ace-tyl-D-phenylalanine shows that the hydrolysis rate can reach to 84%, the converting batches can reach six times or more,and the activity can keep over 70 hours.

关 键 词：N-乙酰-D-氨基酸 D-氨基酸酰化酶 固定化酶 酶学特性 

分 类 号：Q814[生物学—生物工程]