Identification of bacterium degrading xylan and the characteristics of its xylanase | 木聚糖降解细菌的鉴定及其木聚糖酶的特性

Chinese. [目的] 探讨木聚糖酶的生理生化特性。[方法] 采用平板活性筛选法从不同环境样品中筛选出木聚糖降解能力最强的菌株进行鉴定并对其所产粗木聚糖酶的特性进行研究。[结果] 菌株GXM1 被鉴定为洋葱假单胞菌, 菌株GXM4 为类芽孢杆菌。菌株GXM1 所产木聚糖酶的最适pH 为6.0 , 最适温度为55 ℃, 菌株GXM4 所产木聚糖酶的最适pH 为6.0 , 最适温度为50 ℃。2 株菌株所产的木聚糖酶在40 ℃以下较为稳定。Mn2 + 、Ca2 + 和Zn2 + 对菌株GXM1 所产木聚糖酶有显著的激活作用, 而Cu2 + 、Fe2 + 和Fe3 + 对其有显著的抑制作用;Ca2 + 和Fe3 + 对菌株GXM4 所产木聚糖酶有显著的激活作用, 而Mn2 + 、Zn2 + 和Fe2 + 对其有显著的抑制作用。[结论] 为高效木聚糖酶的生产应用奠定了理论基础。

English. [Objective] The aim was to discuss the physiological and biochemical characteristics of xylanase . [Method] The strains with strongest xylan degradation ability were screened from samples in different environment by plate activity screening method and then identified. The characteristics of the crude xylanase produced by the screened strains were studied. [Result] The strain GXM1 was identified as Burkholderia cepacia and the strain GXM4 was identified as Paenibacillus favisporus. The suitable pH value of xylanase produced by the strain GXM1 was 6 .0 and its suitable temperature was 55 ℃. The suitable pH value of xylanase produced by the strain GXM4 was 6 .0 and its suitable temperature was 50 ℃. The xylanase produced by the 2 trains were stable below40 ℃. Mn2+, Ca2+ and Zn2+ had significant activation on the xylanase produced by the strain GXM1, while Cu2+, Fe2+ and Fe3+ had significant inhibitory effect on it. Ca2+ and Fe3+ had significant activation on the xylanase produced by the strain GXM4, while Mn2+, Zn2+ and Fe2+ had significant inhibitory effect on it. [Conclusion] The research laid the theoretical foundation for the production application of efficient xylanase.