共表达木聚糖酶和木糖还原酶生产木糖醇的研究

运用PCR技术扩增出短小芽孢杆菌木聚糖酶A基因,构建分泌型重组质粒pET22-xynA,并构建木糖还原酶重组质粒pET28-xyl1。利用双抗生素抗性将pET22-xynA和pET28-xyl1在E.coliBL21(DE3)plysS中共表达,鉴定了木聚糖酶和木糖还原酶的活性。此外,还对其利用木聚糖生产木糖醇做了初步研究,为将来直接应用玉米芯等农副产品生产木糖醇奠定了基础。

Coexpression of Xylanase and Xylose Reductase for the Production of Xylitol

The xynA gene encoding xylanase was amplified using PCR technique,and cloned into secreted expression vector pET-22b,resulting in the recombinant vector pET22-xynA.Xyl1 gene encoding xylose reductase was inserted in pET-28a(+)to yield the recombinant vector pET28-xyl1.Under screening pressure by ampicillin and kanamycin simultaneously,the activity of xylanase and XR were characterized by co-expression of pET22-xynA and pET28-xyl1 in E.coli BL21(DE3)plysS.Furthermore,xylitol production from xylan by this recombinant E.coli was also studied,which could be the foundation of xylitol production from agricultural by-products in the future.