木聚糖酶TgXyn2的酶学特性研究

Enzymatic Characterization of Xylanase TgXyn2

目的:本研究旨在发掘和研究一种新的低温酸性内切-1,4-β-木聚糖酶TgXyn2并研究其酶学特性,为其在食品等轻工业生产中的实际应用提供理论依据。方法:利用pCold-TF表达质粒在大肠杆菌中异源表达,纯化后检测其酶学特性,并通过同源建模分析其三维结构。结果:该酶的最适温度为35℃,最适pH为5.0,K_(m)为1.287μmol L^(−1),V_(max)为2.083μmol min^(−1)mg^(−1);同源建模结果表明,TgXyn2由2个反向平行的β-折叠和1个α-螺旋构成,是典型的糖苷水解酶GH11家族木聚糖酶。结论:本文研究的TgXyn2具有良好的酶学特性,在食品等行业具有较好的应用潜力。

Objectives:This study aimed to discover a acidic xylanase TgXyn2 with high enzymatic activities at low temperatures,which might have potential application in food industry.Method:TgXyn2 was heterologously expressed in E.coli with the expression vector pCold-TF.Results:The optimum reaction condition of TgXyn2 was 35℃and pH5.0,respectively.Its K_(m) was 1.287μmol L^(−1) and V_(max) was 2.083μmol min^(−1) mg^(−1).Homology modeling showed that TgXyn2 had two antiparallelβ-sheets and anα-helix,which was typical for the GH11 family.Conclusions:TgXyn2 had good enzymatic activities,which has potential application in food industry.