节杆菌LF-Tou2葡萄糖基转移酶是控制絮凝剂聚糖合成的酶。通过对细胞超声破碎使酶释放,经Sephadex G200凝胶色谱和DEAE-Sepharose Fast Flow离子交换色谱对酶进行了纯化。对酶学特性进行了分析,并用5种化学修饰剂对酶分子中5种不同氨基...节杆菌LF-Tou2葡萄糖基转移酶是控制絮凝剂聚糖合成的酶。通过对细胞超声破碎使酶释放,经Sephadex G200凝胶色谱和DEAE-Sepharose Fast Flow离子交换色谱对酶进行了纯化。对酶学特性进行了分析,并用5种化学修饰剂对酶分子中5种不同氨基酸残基与催化活性之间的关系进行了研究。结果表明:该酶的分子质量为14315Da;样品中w(α-螺旋)=31.7%,w(β-转角)=34.1%,w(无规卷曲)=34.2%。Km为2.752μmol,Vmax为58.056μmol/min;Mn2+是酶活性强有力的激活剂,Fe2+次之。酪氨酸和二硫键是酶分子的结构基团,色氨酸、巯基和组氨酸是酶活力的必需基团,在必需基团中色氨酸最关键。展开更多
To further understand characters of alkaline phosphatase and provide reference for in-depth study of the mechanism of NFRKN-1 invading into knot nematode and its development and utilization, the effects of metal ions,...To further understand characters of alkaline phosphatase and provide reference for in-depth study of the mechanism of NFRKN-1 invading into knot nematode and its development and utilization, the effects of metal ions, organic reagents and chemical modifier on activity of alkaline phosphatase from DFRKN-1 were analyzed in the paper. The results showed that Mg2+, Ba2+ and K+ under certain concentrations activated enzyme significantly and Zn2+ could inhibit enzyme activity. Methanol, ethanol and ethylene glycol inhibited enzyme activity in similar degrees. Histidine residue and Lysine residue are essential groups of alkaline phosphatase; sulfhydryl of cysteine was not an essential group, but disulfide bond played an important role in maintaining the active conformation of alkaline phosphatase.展开更多
文摘节杆菌LF-Tou2葡萄糖基转移酶是控制絮凝剂聚糖合成的酶。通过对细胞超声破碎使酶释放,经Sephadex G200凝胶色谱和DEAE-Sepharose Fast Flow离子交换色谱对酶进行了纯化。对酶学特性进行了分析,并用5种化学修饰剂对酶分子中5种不同氨基酸残基与催化活性之间的关系进行了研究。结果表明:该酶的分子质量为14315Da;样品中w(α-螺旋)=31.7%,w(β-转角)=34.1%,w(无规卷曲)=34.2%。Km为2.752μmol,Vmax为58.056μmol/min;Mn2+是酶活性强有力的激活剂,Fe2+次之。酪氨酸和二硫键是酶分子的结构基团,色氨酸、巯基和组氨酸是酶活力的必需基团,在必需基团中色氨酸最关键。
基金Supported by Key Laboratory Project of State Ethnic Affairs Commission (2010SY12)
文摘To further understand characters of alkaline phosphatase and provide reference for in-depth study of the mechanism of NFRKN-1 invading into knot nematode and its development and utilization, the effects of metal ions, organic reagents and chemical modifier on activity of alkaline phosphatase from DFRKN-1 were analyzed in the paper. The results showed that Mg2+, Ba2+ and K+ under certain concentrations activated enzyme significantly and Zn2+ could inhibit enzyme activity. Methanol, ethanol and ethylene glycol inhibited enzyme activity in similar degrees. Histidine residue and Lysine residue are essential groups of alkaline phosphatase; sulfhydryl of cysteine was not an essential group, but disulfide bond played an important role in maintaining the active conformation of alkaline phosphatase.