绿色木霉纤维素酶CBHI基因的克隆与原核表达

Cloning and Expression of CBHI Gene from Trichoderma viride in Escherichia coli

绿色木霉(Trichoderma viride)所产生纤维素酶可将秸秆天然纤维素组分转化为可发酵的糖,不仅对废物进行再利用,还可以减少环境污染。以纤维素酶工业生产菌株绿色木霉Sn-9106总RNA为模板,利用RT-PCR技术反转录合成外切葡聚糖水解酶(CBHI)基因约1545bp的cDNA片段。该序列与GenBank中的cbhI E00389序列比较,氨基酸序列同源性达91%。大肠杆菌BL21原核表达和SDS-PAGE结果表明,重组蛋白分子量约为53kDa,重组酶活力为5.3U.mg-1。

The cellulase produced by Trichoderma viride can convert straw,it can convert the natural cellulose into fermentable sugars.It not only takes use of the natural resources,but also reduces environmental pollution from straw burning in countryside.The cDNA fragments were amplified with RT-PCR by using the total RNA of strain Sn-9106 as template.The cloned cbhI gene fragment was 1545bp.By comparing with sequence E00389,the identity of amino acid sequence was 91%.The cDNA was successfully expressed in Escherichia coli（BL21） and the maximum activity of 5.3U.mg-1 was achieved.The molecular weight of the recombinant enzyme was about 53kDa by SDS-PAGE analysis.