Cheng Yi, Liu Zhengchu, Zeng Jie, Cheng Lifeng, Yan Zhun, Duan Shengwen, Feng Xiangyuan, Zheng Ke, Zheng Xia, Wang Ruijun
Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Xianjiahu West road 348, Changsha, 410205, Hunan, People's Republic of China.
Biotechnol Lett. 2016 Dec;38(12):2089-2096. doi: 10.1007/s10529-016-2204-2. Epub 2016 Sep 15.
To research the inherent properties of the co-expression of three types degumming-related enzymes and breed more powerful degumming strains.
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 and 4.9, respectively.
The co-expression of degumming-related enzyme genes may be applied in industrial tests and represents a novel direction for bio-degumming research.
研究三种脱胶相关酶共表达的内在特性，培育更高效的脱胶菌株。
在大肠杆菌BL21(DE3)中对脱胶过程中至关重要的果胶酸裂解酶基因、木聚糖酶基因和内切-1,4-β-甘露聚糖酶基因的六个串联多聚体进行了共表达和评估。当多聚体中的木糖基因被木糖91基因取代时，木糖91基因与来自DCE-01的内切-1,4-β-甘露聚糖酶和果胶酸裂解酶具有协同作用。筛选出重组体pET-pxm(91x)并将其转化到原始脱胶菌株DCE-01中，这导致酶活性提高。此外，用新工程菌株pET-pxm(91x)/DCE-01处理的样品的失重、还原糖和化学需氧量分别增加到22.5%、460mg/ml和4.9。
脱胶相关酶基因的共表达可应用于工业试验，为生物脱胶研究提供了新方向。
