中国农业科学 ›› 2010, Vol. 43 ›› Issue (1): 192-199 .doi: 10.3864/j.issn.0578-1752.2010.01.023

• 兽医 • 上一篇    下一篇

猪囊尾蚴dUTPase基因的克隆、表达及其产物的酶学活性分析

刘振勇,吕志慧,郑亚东,窦永喜,乔 军,骆学农,张 艳,景志忠,才学鹏
  

  1. (中国农业科学院兰州兽医研究所/家畜疫病病原生物学国家重点实验室/农业部兽医公共卫生重点实验室/甘肃省动物寄生虫病重点实验室)
  • 收稿日期:2008-04-14 修回日期:2008-11-28 出版日期:2010-01-10 发布日期:2010-01-10
  • 通讯作者: 才学鹏

Cloning, Expression of Cysticercus Cellulosae dUTPase and the Determination of Its Enzymatic Activity

LIU Zhen-yong, Lü Zhi-hui, ZHENG Ya-dong, DOU Yong-xi, QIAO Jun, LUO Xue-nong,ZHANG Yan, JING Zhi-zhong, CAI Xue-peng
  

  1. (中国农业科学院兰州兽医研究所/家畜疫病病原生物学国家重点实验室/农业部兽医公共卫生重点实验室/甘肃省动物寄生虫病重点实验室)
  • Received:2008-04-14 Revised:2008-11-28 Online:2010-01-10 Published:2010-01-10
  • Contact: CAI Xue-peng

摘要:

【目的】克隆、表达猪囊尾蚴dUTPase基因并分析其酶学活性。【方法】通过RT-PCR的方法克隆猪囊尾蚴dUTPase基因,将其与pET载体连接并在原核系统中高效表达;表达产物经Ni柱纯化后进行酶学活性测定。【结果】序列分析表明猪囊尾蚴dUTPase基因与六钩蚴的dUTPase基因核苷酸同源性为100%,而且其氨基酸序列中同样存在5个保守基序。SDS-PAGE显示在21kD附近出现与目的蛋白大小相符的特异条带,表达产物经纯化后dUTPase的含量为2.863 mg?mL-1。酶学活性试验证实重组dUTPase能特异性降解dUTP,同时EDTA可以抑制dUTPase的活性;而Mg2+可以增强猪囊尾蚴dUTPase的活性。【结论】成功克隆表达了猪囊尾蚴dUTPase基因并鉴定了它的酶学活性,为进一步研究dUTPase在猪囊尾蚴中的生物学功能奠定了基础,同时也为抗猪囊尾蚴病的药物设计和开发提供了研究基础。

关键词: dUTP焦磷酸酶, 猪囊尾蚴, 原核表达, 酶学活性

Abstract:

【Objective】 In order to develop new drugs against cysticercosis, the dUTPase gene from Cysticercus cellulosae was cloned and expressed. Functionality of the purified recombinant dUTPase was proven by demonstrating catalytic activity towards different substrates. 【Method】 The gene of the dUTPase was obtained by reverse transcription-polymerase chain reaction (RT-PCR) from Cysticercus cellulosae, then cloned into fusion expression vector of pET, and highly expressed in E. coli BL21. The His6-tagged recombinant dUTPase was purified on Ni2+–IDA–Sepharose, and the enzymatic activity was investigated. 【Result】 Analysis showed that the open reading frames (ORFs) of dUTPase genes from both cysticerci and oncospheres shared 100% identity, and five conserved motifs were also found in amino acid sequence. The molecular mass of recombinant dUTPase was 21 kD as judged by SDS-PAGE. After purified, the protein concentration of dUTPase was 2.863mg?mL-1. The analysis of the enzymatic activity indicated that the recombinant dUTPase could catalyse the hydrolysis of dUTP and the activity of enzyme was enhanced by Mg2+ and inhibited by EDTA. 【Conclusion】 The dUTPase from Cysticercus cellulosae has been cloned, expressed and identified, which provided a material foundation for a novel drug design against cysticercosis.

Key words: dUTP pyrophosphatase, cysticercus cellulose, prokaryotic expression, enzymatic activity