叶绿素降解工程菌株的构建

为特异、高效地降解烟叶中的叶绿素,从模式植物拟南芥中克隆获得了叶绿素酶基因At CLH1片段,大小为975 bp。通过构建表达载体p ET28a-At CLH1,并转化大肠杆菌BL21,获得了重组工程菌株。该菌株在30℃下,经0.5 mmol/L IPTG诱导培养22 h,可较好地表达重组蛋白At CLH1,蛋白质电泳图谱显示其大小约为35 ku。该菌株的叶绿素酶活力可达24.9 U/m L,能够明显降解烟叶提取物中的叶绿素,在提升低次烟叶品质方面具有很好的应用前景。

Construction of Chlorophyll Degradation Engineering Bacteria

For the specific and efficient degradation of chlorophyll in tobacco leaves,the chlorophyllase gene AtCLH1 containing a full coding region of 975 bp was cloned from Arabidopsis thaliana.AtCLH1 gene was cloned into vector pET28a,and the vector was then transformed into E.coli BL21 cells,finally the recombinant engineering bacterium was obtained.After culturing under 30 ℃ for 22 h,the protein AtCLH1 could express well with 0.5 mmol/L IPTG(isopropy-β-D-thiogaIactopyranoside) as inducer.Sodium dodecyl sulfate(SDS) fingerprint results showed that the molecular mass of AtCLH1 was 35 ku.The activity of AtCLH1 was 24.9 U/mL,which could degrade the chlorophyll in tobacco extract and had a good application prospect in improving the quality of low quality tobacco.