摘要
采用硫酸铵分级沉淀、HPLC脱盐、离子交换、Superdex G-200凝胶层析等步骤从华美链霉菌(Streptomyces sp.)发酵液中分离纯化L-谷氨酸氧化酶(GLOD),经过SDS-PAGE电泳检测,样品达到电泳级纯,分子量为140ku。对纯化的GLOD研究发现,该酶的最适反应温度为50℃,最适pH值为7.0,温度稳定范围为0℃～50℃,pH稳定范围在6.0～9.0,GLOD催化L-谷氨酸的米氏常数Km为2.1×10-4mol/L,Na+、K+、Mg2+对酶活几乎没有影响,而Hg2+、Cu2+、Ag+均不同程度的抑制酶的活性。
The L-glutamate oxidase（GLOD） produced by Streptomyces sp.was purified by fraction precipitation by ammonium sulfate,HPLC desalination,ion exchange,Superdex G-200 Gel filtration chromatography and other steps.The electrophoresis purity was examined by SDS-PAGE,and the relative molecular weight of purified enzyme is 140ku.The properties of the L-glutamate oxidase were studied.The optimal temperature and pH value were 50℃ and 7.0,respectively.The enzyme was stable between 0℃～50℃ and within pH value 6.0～9.0.The Km value for hydrolyzation of L-glutamic acid by this enzyme was 2.1×10-4mol/L.Metal ions of K＋,Na＋ and Mg2＋ had little effect on the activity of GLOD,but Hg2＋,Cu2＋ and Ag＋ can inhibit the activity of the enzyme.
出处
《中国酿造》
CAS
2012年第1期140-143,共4页
China Brewing
关键词
L-谷氨酸氧化酶
分离
纯化
酶学性质
L-glutamate oxidase
isolation
purification
enzyme properties
