纳豆激酶的分离纯化及其特性研究

从实验室保存的1株高产纳豆激酶菌株出发,进行发酵产酶,确立具有纤溶活力的纳豆激酶的分离纯化工艺,主要通过硫酸铵分级盐析法和Phenyl Sepharose疏水柱层析进行分离纯化,用纤维蛋白平板法测定酶活力,用SDS-PAGE电泳验证为电泳纯,分子质量为28 ku。试验了不同作用温度、pH值和金属离子对NK活力的影响。结果表明,NK的适宜温度为25~50℃,适宜pH值为7.0,Cu2+,Mn2+,Hg2+是其抑制剂,而Mg2+,Ca2+为激活剂。

Study on the Purification of Nattokinase from the Liquid Fermentation and Its Characteristics

Nattokinase(NK) was a kind of fibrinolytic enzyme produced by Bacillus subtilis natto.The enzyme was separated by the ammonium sulfate fractionation and purified by Phenyl Sepharose.The purified enzyme was showed a single protein band in the SDS-PAGE and Mr.28KD.The effects of the temperature,pH value and different metal ions on NK were experimented.The results showed the optimum temperature 25-50℃,pH 7.0 and inhibitor Cu~(2+),Mn~(2+),Hg~(2+) however promoter Mg~(2+),Ca~(2+).It is expected to be a new thrombolytic medicine.