吉林大学学报(理学版)

• 生命科学 • 上一篇    下一篇

玉米半胱氨酸蛋白酶的原核表达及酶学性质表征

刘回民1,2, 陈方奇2,3, 郑明珠2,3, 程国栋2,3, 詹冬玲2,3, 刘景圣2,3   

  1. 1. 吉林农业大学 生命科学学院, 长春 130118; 2. 吉林农业大学 小麦和玉米深加工国家工程实验室, 长春 130118;3. 吉林农业大学 食品科学与工程学院,
    长春 130118
  • 收稿日期:2014-12-09 出版日期:2015-09-26 发布日期:2015-09-29
  • 通讯作者: 刘景圣 E-mail:liujs1007@vip.sina.com

Prokaryotic Expression and Characterization ofCysteine Protease from Zea mays

LIU Huimin1,2, CHEN Fangqi2,3, ZHENG Mingzhu2,3, CHENG Guodong2,3,ZHAN Dongling2,3, LIU Jingsheng2,3   

  1. 1. College of Life Science, Jilin Agricultural University, Changchun 130118, China; 2. National Engineering Laboratory for Wheat and Corn Deep Processing, Jilin Agricultural University, Changchun 130118, China;3. College of Food Science and Engineering, Jilin Agricultural University, Changchun 130118, China
  • Received:2014-12-09 Online:2015-09-26 Published:2015-09-29
  • Contact: LIU Jingsheng E-mail:liujs1007@vip.sina.com

摘要:

以玉米基因组DNA为模板扩增获得玉米半胱氨酸蛋白酶基因(zmCP1), 先将其克隆至pET28a(+)原核表达载体中, 再转化至大肠杆菌BL21(DE3)中. 对重组酶进行诱导表达后经聚丙烯酰胺凝胶电泳(SDS-PAGE)和蛋白免疫印迹(Western blotting)鉴定, 经Ni柱纯化后其质量分数大于95%. 利用二肽荧光底物(R-AMC)和四肽荧光底物(LAFR-AMC)进行酶反应动力学实验, 证明该酶对小底物R-AMC具有更好的亲和力和催化活性. 重组酶的酶学性质研究表明, 该酶最适温度为55 ℃, 最适pH值为6.0, 在90 ℃下的半衰期为39.82 min.

关键词: 玉米, 半胱氨酸蛋白酶, 原核表达, 酶学性质

Abstract:

Cysteine protease from Zea mays (zmCP1) was cloned by PCR with corn genome DNA as template, and ligated to pET28a(+), expressed in E.coli BL21(DE3). The recombinant enzyme was identified by SDSPAGE and Western blotting, finally purified through Nichelating affinity chromatography. The purity can reach 95%. The properties characterization of zmCP1 showed that the optimal temperature was 55 ℃, and the optimal pH was 6.0, the halftime was 39.82 min at 90 ℃. The enzyme kinetics researches with RAMC and LAFR-AMC as substrate show that zmCP1 has better affinity and catalytic activity to small substrate.

Key words: Zea mays, cysteine protease, prokaryotic expression, enzyme properties

中图分类号: 

  • Q786