北京大学学报(自然科学版)

α-胰凝乳蛋白酶在不同介质中稳定性的研究

沈鸿雁, 周闯, 叶蕴华, 田桂玲   

  1. 北京大学化学与分子工程学院,教育部生物有机重点实验室,北京,100871
  • 收稿日期:2003-06-24 出版日期:2004-07-20 发布日期:2004-07-20

Stability of α-Chymotrypsin in Different Media

SHEN Hongyan, ZHOU Chuang, YE Yunhua, TIAN Guiling   

  1. Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, E-mail: gltian@sina.com
  • Received:2003-06-24 Online:2004-07-20 Published:2004-07-20

摘要: 测定了α-胰凝乳蛋白酶在不同介质中的活性及稳定性。研究了有机溶剂性质、pH值、离子强度及离子类型对α-胰凝乳蛋白酶活性与稳定性的影响,并通过CD谱初步研究了α-胰凝乳蛋白酶在不同pH值缓冲液中的二级结构变化。研究结果表明,α-胰凝乳蛋白酶在某些有机溶剂中能在较长时间内维持较高的酶活性。α-胰凝乳蛋白酶在3种pH值不同的缓冲液中的CD谱表明其在pH=10.0的稀溶液中的α-螺旋和(或)β-折叠含量较高。在不同pH值条件下,离子强度对α-胰凝乳蛋白酶的活性与稳定性的影响不同。

关键词: α-胰凝乳蛋白酶, 稳定性, pH值, 离子强度, CD谱

Abstract: The activity and stability of α-chymotrypsin in different media were studied. The influence of organic solvents, pH values, ionic strengths and ionic types on the stability of α-chymotrypsin was preliminarily studied. The secondary structure of α-chymotrypsin in different pH was studied by circular dichroism (CD) spectra. The results showed that α-chymotrypsin could maintain its high activity and stability in some organic solvents for a long time. And the CD spectra of α-chymotrypsin in solutions with different pH showed that in pH 10.0, the content of α-helix and (or) β-sheet of α-chymotrypsin was higher than that in pH 5.0 or pH 7.0. The influence of ionic strengths on the activity and stability of α-chymotrypsin was different in different pH values.

Key words: α-chymotrypsin, stability, pH value, ionic strength, CD spectra

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