高温蛋白酶生产菌BY25不同培养基下产酶差异研究

Differences in Enzyme Production Induced by Fermentation Media of a Moderate Thermophilic Strain Bacillus subtilis BY25

枯草芽孢杆菌是一种广泛存在于土壤中的产酶细菌,在环境领域也具有广阔的应用前景。本文以一株产高温蛋白酶枯草芽孢杆菌BY25为研究对象,比较添加不同有机氮源的产酶培养基进行发酵时,各处理中枯草芽孢杆菌胞外蛋白酶的组成和产量的差异;并对不同培养基发酵液的粗酶液组分进行酶学性质分析和明胶酶谱检测。结果表明,枯草芽孢杆菌BY25在不同培养基条件下会出现差异性产酶,产酶培养基中添加麸皮有利于中性金属蛋白酶(Npr)的产生,而添加豆饼粉则有利于枯草菌素(Apr)的产生。

Bacillus subtilis secret different proteolytic enzymes into culture media during stationary phase.Two major proteases are Subtilisin （Apr） and Metelloproteinase （Npr）,which account for more than 90％ of total activity.Both of them are of important application on industry.In this study,these two proteases induced by different media components,soybean cake and wheat bran were observed.After B.subtilis BY25 fermentation,enzyme property examination showed Apr was induced by soybean cake.Gelatin zymograph was then operated and different bands were revealed among enzyme solutions.However,35 KD Npr protein was observed only in the enzyme solution fermented with wheat bran.