生物技术通报 ›› 2013, Vol. 0 ›› Issue (4): 110-115.

• 研究报告 • 上一篇    下一篇

谷氨酸棒杆菌L-天冬氨酸α-脱羧酶基因的克隆及重组酶性质研究

石增秀 崔文璟 周丽 周哲敏   

  1. 江南大学生物工程学院 工业生物技术教育部重点实验室,无锡 214122
  • 收稿日期:2012-11-01 修回日期:2013-04-22 出版日期:2013-04-22 发布日期:2013-04-22
  • 作者简介:石增秀,女,硕士研究生,研究方向:发酵工程;E-mail:shitouszx@163.com
  • 基金资助:
    国家自然科学基金项目(31070711),新世纪优秀人才项目(NCET-10-0461)

Cloning and Characterization of L-aspartate-α-decarboxylase from Corynebacterium glutamicum

Shi Zengxiu, Cui Wenjing, Zhou Li, Zhou Zhemin   

  1. The Key Laboratory of Industrial Biotechnology of the Ministry of Education,School of Biotechnology, Jiangnan University,Wuxi 214122
  • Received:2012-11-01 Revised:2013-04-22 Published:2013-04-22 Online:2013-04-22

摘要: 从谷氨酸棒杆菌(Corynebacterium glutamicum)中克隆得到L-天冬氨酸α-脱羧酶基因panD。将该基因连接到pET- 24a 载体上,并在Escherichia coli BL21(DE3)中实现了成功表达。蛋白电泳检测显示,PanD 自裂解后形成的α 亚基和β 亚基,即 PanD 重组酶具有自身加工功能。重组酶的比酶活高达2.60 U/mg(156 mmol/g?h)。酶学性质研究表明,其最适温度为55℃,最适 pH 为7.0。80℃条件下,PanD 的半衰期约为40 min。在37℃,pH7.5 条件下,Km 值为4.26 mmol/L,Vmax 为35.97 nmol/min,kcat 为1.02/s, 催化效率kcat/Km 为0.24 L/mmol?s。

关键词: L-天冬氨酸α-脱羧酶, 谷氨酸棒杆菌, 表达, 纯化, 酶学性质

Abstract: L-aspartate-α-decarboxylase gene panD from Corynebacterium glutamicum was cloned and efficiently expressed in Escherichia coli BL21(DE3). The α and β subunits of PanD were observed by Tris-tricine SDS-PAGE, indicating that the PanD was successful processed by self cleavage. The specific activity of the recombinant enzyme was as high as 2.60 U/mg(156 mmol/g?h). The optimum temperature was 55℃ and the optimum pH was 7.0. Under the condition of 80℃ , the half-life of PanD was approximately 40 min. Under the condition of 37℃ and pH7.5, the Km value was 4.26 mmol/L, the Vmax value was 35.97 nmol/min, the kcat value was 1.02/s and the catalytic efficiency(kcat/Km)was 0.24 L/mmol?s.

Key words: L-aspartate-α-decarboxylase, Corynebacterium glutamicum, Expression, Purification, Enzymatic properties