【作者】 白复芹； 刘晓光； 李惠； 于丹； 李静； 高克祥；

【Author】 BAI Fu-qin,LIU Xiao-guang, LI Hui, YU Dan,LI Jing,GAO Ke-xiang (College of Plant Protection, Shandong Agricultural University, Taian 271018,China; Institute of Life Sciences, Jiangsu University;Centre for Vocational Education of Anguo City, Hebei Province)

【机构】 山东农业大学植物保护学院； 江苏大学生命科学研究院； 河北省安国市职业教育中心；

【摘要】 以胶体几丁质为诱导物,内生菌螺旋毛壳(Chaetomium spirole)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Hg2+、Fe3+、Zn2+、Cu2+、Mg2+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 U ml-1。更多还原

【Abstract】 The crude extract with chitinase activity induced by colloidal chitin was obtained from Chaetomium spir-ale 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 hy-drophobic 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 Hg2+ ,Fe3+ ,Zn2+ ,Cu2+ and Mg2+ and slightly stimulated by Na2+. The Km and Vmax values for the chitinase, using colloidal chitin as substrate, were 1. 72mg ml-1 and 21.18 U ml-1, respective-更多还原