摘要
从海水中分离筛选到一株高活力的海洋琼胶降解菌2.2-g。通过硫酸铵盐析、透析袋透析、离子交换柱层析和凝胶柱层析,得到了电泳纯的琼胶酶样品,通过SDS-PAGE电泳,其分子量约为55kDa。该琼胶酶的最适pH值和温度分别为7.0和55℃。Mg2+和Ca2+对酶促反应有较强的促进作用,而Mn2+、Zn2+、NH4+、EDTA和SDS等则有不同程度的抑制作用。酶解产物的质谱和核磁共振谱结果证明,该琼胶酶降解琼胶后得到由新琼二糖、新琼四糖、新琼六糖组成的混合物,证明该琼胶酶为β-琼胶酶。
An agar-decomposing strain 2.2-g was isolated and selected from sea water. The enzyme was achieved by amrnonium, dialysis and DEAE-cellulose separation, and its molecular mass was determined as 55 kDa. The most suitable pH and temperature of the enzyme were 7.0 and 55℃, respectively. Mg〉 and Ca2＋ can be used as enzyme activators for this extracelhilar agarase, while Mn2＋, Zn2＋, NH4＋, EDTA and SDS partially or completely inhibited its activity. MS and NMR analysis showed that the enzyme is a β-agarase, which was further validated by the components of its degraded products （ neoagarobiose, neoagarotetose and neoagarohexaose）.
出处
《现代食品科技》
EI
CAS
2008年第12期1217-1221,共5页
Modern Food Science and Technology
关键词
海洋细菌
Β-琼胶酶
酶学性质
酶解产物
marine bacteria
13-agarase
Enzymeology properties
Enzymatic products
作者简介
蔡俊鹏（1963-），男，教授，主要从事海洋生物技术的研究
