Nakada T, Maruta K, Mitsuzumi H, Kubota M, Chaen H, Sugimoto T, Kurimoto M, Tsujisaka Y
Hayashibara Biochemical Laboratories, Inc., Okayama, Japan.
Biosci Biotechnol Biochem. 1995 Dec;59(12):2215-8. doi: 10.1271/bbb.59.2215.
A novel enzyme, maltooligosyl trehalose trehalohydrolase from Arthrobacter sp. Q36 was purified from a cell-free extract to an electrophoretically pure state by successive column chromatography on Sepabeads FP-DA13, Butyl-Toyopearl 650M, DEAE-Toyopearl 650S, and Toyopearl HW-55S. The enzyme specifically catalyzed the hydrolysis of the alpha-1,4-glucosidic linkage that bound the maltooligosyl and trehalose moieties of maltooligosyl trehalose. The Km of the enzyme for maltosyl trehalose, maltotriosyl trehalose, maltotetraosyl trehalose, and maltopentaosyl trehalose was 5.5 mM, 4.6 mM, 7.0 mM, and 4.2 mM, respectively. The enzyme had a molecular mass of 62,000 by SDS-polyacrylamide gel electrophoresis and a pI of 4.1 by gel isoelectrofocusing. The N-terminal amino acid of the enzyme was threonine. The enzyme showed the highest activity at pH 6.5 and 45 degrees C, and was stable from pH 5.0 to 10.0 and up to 45 degrees C. The activity was inhibited by Hg2+, Cu2+, Fe2+, and Zn2+.
从节杆菌属Q36菌株中分离出一种新型酶——麦芽寡糖基海藻糖海藻糖水解酶，通过在Sepabeads FP - DA13、丁基 - Toyopearl 650M、DEAE - Toyopearl 650S和Toyopearl HW - 55S柱上连续进行层析，从无细胞提取物中纯化至电泳纯状态。该酶特异性催化连接麦芽寡糖基海藻糖中麦芽寡糖基和海藻糖部分的α - 1,4 - 糖苷键的水解。该酶对麦芽三糖基海藻糖、麦芽四糖基海藻糖、麦芽五糖基海藻糖和麦芽六糖基海藻糖的Km值分别为5.5 mM、4.6 mM、7.0 mM和4.2 mM。通过SDS - 聚丙烯酰胺凝胶电泳测定该酶的分子量为62,000，通过凝胶等电聚焦测定其pI为4.1。该酶的N端氨基酸为苏氨酸。该酶在pH 6.5和45℃时表现出最高活性，在pH 5.0至10.0以及高达45℃的条件下稳定。其活性受到Hg2 +、Cu2 +、Fe2 +和Zn2 +的抑制。
