EL112发酵条件的确定及弹性蛋白酶的纯化研究

Production and Purification of Elastase by EL112 Strain Mediated Fermentation

对本实验室筛选分离到的弹性蛋白酶高产菌株EL112的发酵条件及其所得的弹性蛋白酶进行了纯化研究,其发酵条件为葡萄糖2.0%,酵母粉0.25%,pH7.5,37℃,150r/min的摇瓶发酵;在最佳条件下发酵所得的发酵液经过离心过滤、硫铵沉淀、亲和层析等步骤可使其中的弹性蛋白酶纯化近50倍,收率为51.2%。纯化后的酶蛋白比活达到4576U/mg。采用垂直板状SDS-PAGE电泳分析,得出该菌株产生得弹性蛋白酶蛋白相对分子质量为27000。

The fermentation by elastase-producing EL112 was studied and the achieved elastase was purified by laminar analysis. The best fermentation conditions were found as glucose 2.0 %, powdery microzyme 0.25 %, pH 7.5, temperature 37 ℃, and shaking speed 150 r/min. The achieved fermented liquid was centrifugal filtrated, grading precipitated by （NH4）2SO4 and then purified by affinity chromatography, giving crud enzyme with specific activity of 4576 U/mL and yield of 51.2%. SDS-PAGE showed that the molecular weight of the elastase was 27 000.