首页 | 官方网站   微博 | 高级检索  
     

蚯蚓纤溶酶基因(Efp-Ⅰ)在大肠杆菌中的克隆、表达及活性分析
引用本文:赵晓瑜,李晓霞,侯艳,静天玉.蚯蚓纤溶酶基因(Efp-Ⅰ)在大肠杆菌中的克隆、表达及活性分析[J].生物工程学报,2007,23(3):452-456.
作者姓名:赵晓瑜  李晓霞  侯艳  静天玉
作者单位:河北大学生命科学学院,保定071002
基金项目:河北省生物工程重点学科项目
摘    要:从GenBank查询到的蚯蚓纤溶酶(earthworm fibrinolyti cenzyme,EFE)基因序列中,只有AY438624翻译的蛋白质序列与天然EfP-Ⅰ在N-端具有较高的相似性。根据该基因的5′与3′序列设计引物,通过RT-PCR从赤子爱胜蚓(Eisenia fetida)获得一个完整的基因(GenBank,DQ418454)。序列分析证明,由该基因编码蛋白质的N-末端与天然EfP-Ⅰ的N-末端的氨基酸顺序完全相同。ScanProsite prediction programs分析显示,该基因与AY438624相似性极高,二者均属于胰蛋白酶家族;不同的是,该基因编码蛋白质的序列中含有N-糖苷键的结构域,所以DQ418454是EfP-Ⅰ中的一个新基因。在此基础上,构建了该基因的原核表达载体pMAL-c2X-Efp-Ⅰ,并进行了转化、诱导和表达。Western blotting证明,表达产物同时具有MBP和EfP-Ⅰ的抗原特异性,是MBP和EfP-Ⅰ的融合蛋白(MBP-EfP-Ⅰ)。经亲和层析分离纯化的MBP-EfP-Ⅰ,在酪蛋白平板和纤维蛋白平板上表现出明显的纤溶酶活性。

关 键 词:赤子爱胜蚓  蚯蚓纤溶酶  基因克隆  融合表达  纤溶酶活性
文章编号:1000-3061(2007)03-0452-05
修稿时间:2006-09-252006-12-18

Cloning,Expression of Fibrinolytic Enzyme Gene Efp-Ⅰ from Eisenia fetida in Escherichia coli and Activity Analysis
ZHAO Xiao-Yu,LI Xiao-Xia,HOU Yan,JING Tian-Yu.Cloning,Expression of Fibrinolytic Enzyme Gene Efp-Ⅰ from Eisenia fetida in Escherichia coli and Activity Analysis[J].Chinese Journal of Biotechnology,2007,23(3):452-456.
Authors:ZHAO Xiao-Yu  LI Xiao-Xia  HOU Yan  JING Tian-Yu
Affiliation:College of Life Sciences, Hebei University, Baoding 071002, China
Abstract:Earthworm fibrinolytic enzyme (EFE) is a group of protease having fibrinolytic and plasminogen-activator activities isolated from earthworm. Molecular biology research showed that there were 21 EFE coding sequences, in which only one sequence, AY438624, whose translated protein had similar N-terminal amino-acid sequence to EfP-I purified from Eisenia fetida. To obtain coding sequence of EfP-I , we designed specific primers according to 5' and 3' sequences of AY438624. A new DNA sequence was obtained by RT-PCR, sequence analysis showed that the protein translated from the coding sequence had identical N-terminal amino-acid sequence with EfP-I purified from Eisenia fetida and Lumbricus rubellus. Analysis by using ScanProsite prediction programs proved that the sequence had high similarity to AY438624 and belonged to trypsin family of serine protease. But there was difference between two sequences, that was there was a domain of characteristic amino acids of N-glycosylation site Asn-Xaa-Ser/Thr(N-x-S/T)in the new sequence (DQ418454). Then the expressed vector pMAL-c2X-Efp-I was constructed by cloning the gene into the plasmid pMAL-c2X, and was transformed to E. coli TB1. After induction and expression of the recombinant, the product MBP-EfP-I was purified by MBP affinity chromatography. Western blotting analysis showed that the product reacted with both anti-MBP and anti-EfP-I -1 serum. Casein plate test and fibrin plate test showed that the protein expressed had fibrinolytic activity.
Keywords:Eisenia fetida  earthworm fibrinolytic enzymes  gene cloning  fusion expression  fibrinolytic activity
本文献已被 CNKI 维普 万方数据 等数据库收录!
点击此处可从《生物工程学报》浏览原始摘要信息
点击此处可从《生物工程学报》下载全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号