Construction and co-expression of polycistronic plasmids encoding bio-degumming-related enzymes to improve the degumming process of ramie fibres.
Ключови думи
Резюме
OBJECTIVE
To research the inherent properties of the co-expression of three types degumming-related enzymes and breed more powerful degumming strains.
RESULTS
Six tandem multimers of the pectate lyase gene, the xylanase gene, and the endo-1,4-β-mannanase gene, which are essential for degumming process, were co-expressed and evaluated in Escherichia coli BL21(DE3). The xyl91 gene had a synergistic effect with endo-1,4-β-mannanase and pectate lyase from DCE-01, when xyl gene was replaced with xyl91 in the multimer. The recombinant pET-pxm(91x) was selected and transformed into the original degumming strain DCE-01, which led to an enzymatic activity improvement. Furthermore, the weight loss, reducing sugar and COD value of the sample treated with the new engineered strain pET-pxm(91x)/DCE-01 increased to 22.5 %, 460 mg ml-1 and 4.9, respectively.
CONCLUSIONS
The co-expression of degumming-related enzyme genes may be applied in industrial tests and represents a novel direction for bio-degumming research.
