Coexpression of β-mannanase and xylanase genes in Escherichia coli

Abstract:

[Objective] β-mannanase and xylanase are hemicellulase, which are already used in many areas of industrial and agricultural. The aim of this study was to coexpress two hemicellulase genes in E. coli (Escherichia coli). [Methods] The β-mannanase and xylanase genes were cloned from Bacillus subtilis BE-91, then linked together by a common restriction enzyme site and inserted into the pET28a(+), establishing a coexpression strain named B.pET28a-man-xyl for the extracellular production of β-mannanase and xylanase in E.coli. [Results] After being induced 21 h, the specific activities of β-mannanase and xylanase were 713.34 U/mL and 1455.83 U/mL, respectively. [Conclusion] The result of SDS-PAGE analysis, hydrolytic ring detection and enzyme activity determination showed that each enzyme was expressed extracellularly as individual functional proteins. In addition, comparing with β-mannanase and xylanase degraded hemicellulose alone, the effection of compound enzymes are much better. The successful construction of a strain which produces xylanase and β-mannanase will be helpful for the study and production of hemicellulases preparation.