食品科学

• 生物工程 • 上一篇    下一篇

猪脑乙酰胆碱酯酶的分离纯化和性质研究

王 洁,李 星,王红扬,唐云明   

  1. 西南大学生命科学学院,重庆市甘薯工程研究中心,三峡库区生态环境教育部重点实验室,重庆 400715
  • 出版日期:2015-02-15 发布日期:2015-02-10

Purification and Characterization of Acetylcholinesterase from Porcine Brain

WANG Jie, LI Xing, WANG Hongyang, TANG Yunming   

  1. Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, Chongqing Sweet-potato Engineering
    Research Center, College of Life Science, Southwest University, Chongqing 400715, China
  • Online:2015-02-15 Published:2015-02-10

摘要:

通过离心、硫酸铵分级沉淀、DEAE-Sepharose和Superdex-200层析等步骤,从猪脑中获得电泳纯乙酰胆碱酯酶,该酶比活力和纯化倍数分别为2.05 U/mg和26.97,酶活回收率为11.95%;该酶分子质量为257.30 kD,亚基为66.94 kD;以碘化硫代乙酰胆碱为底物时,酶的最适反应温度为37 ℃,最适pH值为7.4,且在40 ℃以下,pH 6.0~8.0有较好的稳定性;最适底物浓度为4.0 mmol/L,Km为0.94 mmol/L。Ba2+和Zn2+对该酶有强烈的抑制作用,而低浓度Mg2+对该酶有激活作用。

关键词: 乙酰胆碱酯酶, 猪脑, 分离纯化, 性质

Abstract:

Acetylcholinesterase (AChE) was purified from porcine brain by consecutive steps including centrifugation,ammonium sulfate fractionation, DEAE-Sepharose chromatography and Superdex-200 gel filtration chromatography. Thepurified AChE exhibited a specific activity of 2.05 U/mg, with 26.97-fold purification and an activity yield of 11.95%. Therelative molecular weight of AChE was 257.30 kD, and the subunit molecular weight was 66.94 kD. The optimal pH andtemperature for the enzyme were 7.4 and 37 ℃, respectively. The enzyme was stable below 40 ℃ and in the pH range of6.0–8.0. At an optimal substrate concentration of 4.0 mmol/L, the apparent Km was 0.94 mmol/L. The activity of AChE wasinhibited by Ba2+ or Zn2+ , but enhanced by Mg2+.

Key words: acetylcholinesterase, porcine brain, isolation and purification, characterization

中图分类号: