摘要
以胶体几丁质为诱导物,内生菌螺旋毛壳(Chaetomium spirale)ND35通过在SMCS液体培养基中振荡培养,获得了具几丁质酶活性的粗酶液。经硫酸铵沉淀、DEAE-Sepharose阴离子交换层析及Phenyl-Sepharose疏水层析,并通过SDS-PAGE鉴定,纯化了一种分子量约为42kDa的几丁质酶。其最适反应温度为40℃,在30℃以下很稳定；最适pH值为5．5,在pH 5-8．5范围内均较稳定；酶活性受Hg\+\{2+\}、Fe\+\{3+\}、Zn\+\{2+\}、Cu\+\{2+\}、Mg\+\{2+\}等金属离子不同程度的抑制,Na+对酶有轻微的激活作用；以胶体几丁质为底物时,该酶的米氏常数Km为1．72mg ml\+\{-1\},最大反应速度Vmax为21．18 Uml\+\{-1\}。
The crude extract with chitinase activity induced by colloidal chitin was obtained from Chaetomium spirale ND35 in SMCS liquid medium. The chitinase was purified by ammonium sulfate precipitation, electrophoretic homogeneit and DEAE Sepharose Fast Flow anion -exchange chromatography, and Phenyl Sepharose Fast Flow hydrophobic chromatography. Its molecular weight was ca. 42 kDa analyzed by SDS -PAGE. The purified chitinase functioned optimally at 40℃ and pH 5.5, and was stable within a broad range of pH 5 - 8.5 and below 30℃. The chitinase activity was inhibited by Hg^2＋ ,Fe^3＋ ,Zn^2＋ ,Cu^2＋ and Mg^2＋ and slightly stimulated by Na ^＋ The K. and V~ values for the chitinase, using colloidal chitin as substrate, were 1. 72mg ml^-1 and 21.18 U ml^-1, respectively.
出处
《莱阳农学院学报》
2006年第4期268-271,共4页
Journal of Laiyang Agricultural College
基金
国家自然科学基金(30100143
30571498)山东农业大学青年创新基金项目(23406)
关键词
螺旋毛壳ND35
几丁质酶
纯化
酶学性质
Chaetomium spirale ND35
chitinases purification enzymatic properties
