采用中空纤维膜超滤和葡聚糖凝胶层析相结合的方法对黑曲霉N5-5单宁酶进行纯化,然后对纯酶性质进行测定。结果显示,黑曲霉N5-5单宁酶用该方法纯化后,可纯化近20倍,酶活力可回收23.30%。对纯酶作十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析,...采用中空纤维膜超滤和葡聚糖凝胶层析相结合的方法对黑曲霉N5-5单宁酶进行纯化,然后对纯酶性质进行测定。结果显示,黑曲霉N5-5单宁酶用该方法纯化后,可纯化近20倍,酶活力可回收23.30%。对纯酶作十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析,可知黑曲霉N5-5单宁酶为分子质量64.2 k D的单肽链蛋白。纯酶的酶促反应最适温度为45℃,且在25~45℃范围内热稳定性良好;酶促反应最适p H值为5.0,且在p H 5.0~5.5范围内酸碱稳定性良好。另外,反应动力学测定结果表明,该酶对底物没食子酸丙酯的米氏常数K_m为0.916 mmol/L,最大反应速率vmax为0.877 mmol/(L·min)。展开更多
Highly ionized Spectra from sulfur obtained at an energy of 80 MeV have been studied in the 19.0～53.0 nm wavelength range. Radiative lifetimes for some n =2 level in Be+-like S ⅩⅢwere measured using he beam-foil ti...Highly ionized Spectra from sulfur obtained at an energy of 80 MeV have been studied in the 19.0～53.0 nm wavelength range. Radiative lifetimes for some n =2 level in Be+-like S ⅩⅢwere measured using he beam-foil time of flight method. The results, using an arbitrarily normalized decay curves analysis, are compared with theoretical predictions and earlier measurement.展开更多
文摘采用中空纤维膜超滤和葡聚糖凝胶层析相结合的方法对黑曲霉N5-5单宁酶进行纯化,然后对纯酶性质进行测定。结果显示,黑曲霉N5-5单宁酶用该方法纯化后,可纯化近20倍,酶活力可回收23.30%。对纯酶作十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析,可知黑曲霉N5-5单宁酶为分子质量64.2 k D的单肽链蛋白。纯酶的酶促反应最适温度为45℃,且在25~45℃范围内热稳定性良好;酶促反应最适p H值为5.0,且在p H 5.0~5.5范围内酸碱稳定性良好。另外,反应动力学测定结果表明,该酶对底物没食子酸丙酯的米氏常数K_m为0.916 mmol/L,最大反应速率vmax为0.877 mmol/(L·min)。
文摘Highly ionized Spectra from sulfur obtained at an energy of 80 MeV have been studied in the 19.0～53.0 nm wavelength range. Radiative lifetimes for some n =2 level in Be+-like S ⅩⅢwere measured using he beam-foil time of flight method. The results, using an arbitrarily normalized decay curves analysis, are compared with theoretical predictions and earlier measurement.
