食品科学 ›› 2012, Vol. 33 ›› Issue (19): 254-258.

• 生物工程 • 上一篇    下一篇

巨大芽孢杆菌产胞外核糖核酸酶的分离纯化及部分酶学性质研究

赵 芯,成丽丽,邓 玉,敬海明,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
  • 收稿日期:2011-07-25 修回日期:2012-08-10 出版日期:2012-10-15 发布日期:2012-09-17
  • 通讯作者: 唐云明 E-mail:tbright@swu.edu.cn

Purification and Partial Characterization of Extracellular Ribonuclease from Bacillus megaterium

  • Received:2011-07-25 Revised:2012-08-10 Online:2012-10-15 Published:2012-09-17
  • Contact: Yum-Ming Tang Yum-Ming E-mail:tbright@swu.edu.cn

摘要: 巨大芽孢杆菌发酵液经硫酸铵沉淀、CM-Sepharose离子交换层析和Superdex-200凝胶过滤层析,纯化得到核糖核酸酶电泳纯品,并对其性质进行研究。该酶比活力为54272.27U/mg,回收率为11.37%,纯化倍数为606.67倍。该酶分子质量约为33.3kD,最适温度为52.5℃,最适pH值为8.5,在20~40℃以及pH6.0~7.0范围内稳定性较好。Fe2+、Cu2+、SDS、抗坏血酸和草酸对该酶活性有抑制作用。

关键词: 巨大芽孢杆菌, 核糖核酸酶, 分离纯化, 性质

Abstract: After amonanium sulfate precipitation followed by ion-exchange chromatography on CM-Sepharose column and Superdex-200 gel-filtration, ribonuclease from Bacillus megaterium was purified to electrophoretic homogeneity. Some of its enzymological properties were then explored. The results showed that the enzyme was 606.67-fold purified with specific activity of 54272.27 U/mg and recovery rate of 11.37%. The molecular weight was 33.3 kD. Optimum activity of the enzyme was achieved at 52.5 ℃ and pH 8.5. The enzyme displayed good stability at 20—40 ℃ and pH 6.0—7.0. The activity of this enzyme was inhibited by Fe2+, Cu2+, SDS, ascorbic acid and oxalic acid.

Key words: Bacillus megaterium, ribonuclease, isolation and purification, characterization