极端嗜盐古生菌(Natrinema sp.)R6-5胞外嗜盐蛋白酶的纯化和性质研究

Purification and characterization of extracellular halophilic protease from haloarchaea Natrinema sp.R6-5

摘要:

采用bacitracin-Sepharose 4B亲和层析的方法得到凝胶电泳均一的来自极端嗜盐古生菌(Natrinema sp.)R6-5的胞外嗜盐蛋白酶。经SDS-PAGE分析该酶亚基分子量为62kDa。PMSF对它的活性完全抑制,表明它是一种丝氨酸蛋白酶,该酶反应的最适NaCl浓度为3mol/L,最适温度为45℃,最适pH值为8.0。在高盐条件下能维持高活性并十分稳定,具有重要的潜在应用价值。

Abstract:

A halophilic extracellular protease from a halophilic archaea Natrinema sp. R6-5 was purified to SDS-PAGE homogeneity using bacitracin-Sepharose 4B chromatography. A molecular mass of the purified protease subunit was 62KD determined by SDS-PAGE. The protease activity was inhibited by phenylmethylsulfonyl fluoride (PMSF), suggesting that the protease belong to serine protease. The protease exhibited optimum NaCl concentration is 3 mol/L. At the 3 mol/L NaCl concentration, the optimum temperature and the optimum pH were 45℃ and 8.0. The protease could keep high activity and stability in high salt environment and had potential application value.