利用增强子样DNA片段提高几丁酶基因的表达

Study on an Enhancer-like Fragment Increasing the Expression of Chitinase Gene

将来源于环状芽孢杆菌 (Bacilluscirculans)C 2中增强子样DNA片段插入质粒 pCHT1的几丁酶基因 5’ 端 ,构建成重组质粒pCHTX+ 和pCHTX- .将含pCHT1,pCHTX+ 和pCHTX- 质粒的大肠杆菌转化子分别点种在几丁质平板上 ,不同菌株产生了不同大小的水解圈 .利用比色法测定不同菌种的几丁酶活性发现 ,在大肠杆菌中 ,该片段的插入可促进几丁酶基因的表达 。

The XbaI fragment cloned from Bacillus circulans C-2, which could enhance gene transcription was inserted in the upstream site of the chitinase gene in plasmid pCHT1. The resulted recombinant plasmids were called pCHTX + and pCHTX - respectively. The Escherichia coli transformants containing pCHT1, pCHTX +, pCHTX - were incubated on chitin-containing plate respectively, and produced chitin-digested zones with different sizes. At the same time, the chitinase activity of different strains was detected by colorimetric assay. The result showed that the XbaI fragment could increase the expression of chitinase gene in E.coli, but had no positive effect in Bacillus subtilis.