摘要
从一株海洋放线菌株HY-G中纯化得到了一种胞内中性β-葡萄糖苷酶。通过SDS-聚丙烯酰胺凝胶电泳和Superdex 200凝胶柱层析估计酶分子质量分别是43.3 kD和45.0 kD,两者估计值接近,表明该酶是一个单聚体,不含亚基。采用对硝基酚基-β-D-葡萄糖苷(p-NPG)做底物,测得该酶的最适pH和最适温度分别为pH 7.5和40 C。该酶在pH 6.0~7.0最稳定,在70 C保温30 min仍能保留56%的酶活力,表明具有一定的温度稳定性。基于16S rRNA基因的分类研究表明,该菌株属于拟诺卡氏菌属。
An intracellular neutral β-glucosidase was isolated from a marine actinomycetes strain HY-G.The molecular weight of the β-glucosidase was confirmed to be 43.3 kD,by Sodium Dodecyl Sulphate Polyacryl Amide Gel Electrophoresis(SDS-PAGE)and 45.0 kD by size exclusion chromatography.suggesting it might be a monomer.The optimal pH and temperature for p-nitrophenyl-β-D-glucopyranoside(p-NPG) hydrolysing were around 7.5 and 40 C,respectively.The β-glucosidase was most stable at pH 6.0-7.0,and retained 56% activity under 70 C for 30 min.The taxonomy based on 16S rRNA gene suggested that strain HY-G belongs to genus Nocardiopsis.
出处
《海洋科学》
CAS
CSCD
北大核心
2013年第4期41-46,共6页
Marine Sciences
基金
中央财政支持地方高校发展专项资金-应用海洋生物学科研创新团队项目(CXTD20)
江苏省海洋生物技术重点实验室开放课题(2010HS05)
淮海工学院引进人才启动基金项目(KQ08015)资助
关键词
中性β-葡萄糖苷酶
海洋放线菌
拟诺卡氏菌
酶性质
neutral β-glucosidase
marine actinomycetes
Nocardiopsis
enzymological characteristics