新的分离纯化青霉素酰化酶方法的研究

按0．6％(w／v)的比例将皂土加到青霉索酰化酶发酵上清液中，可将酶100％吸附，而吸附的蛋白质仅占发酵上清液中的10％左右。吸附时的pH和无机盐对酶的吸附影响不大。使用不同pH和种类的缓冲液洗涤皂土－酶复合物，不能将酶洗脱，但可洗脱15％左右吸附的杂蛋白。使用含10％以上的PEG和NaCl的磷酸缓冲液可将酶全部洗脱．酶纯化25倍，浓缩6倍左右。此法特点是简便，酶活力收率高，可在常温下操作，也可直接从未除菌体的发酵液中提取酶，具有工业应用价值。

Study on Isolation and Purification of Penicillin Acylase by Adsorption on Bentonite

Bentonite I as an absorbent according to 0. 65% (w/v) was added into the supernatant of fermentation broth for adsorption of penicillin acylase from Bacillus megatherium. It found that 100% activity of penicillin acylase and about 10% protein in the supernatant were adsorbed. The adsorption of enzyme was not obviously changed by different pH and salt .concentration of the supernatant. Verious kinds of buffer having different pH were used to wash the adsorbent-enzyme complex. Only 1 % enzyme activity adsorbed was washed out, however, it can wash out about 15% protein adsorbed. When phosphate buffer containing 10% PEG and NaCl as an eluent was used to elute the complex, 100% of enzyme activity adsorbend on the complex would be eluted, and purification and concentration of enzyme could achieve about 25 and 6 fold, respectively. The isolation and purification process can be carried out at room temperature. Its characters were very simple and high recovery yield of enzyme activity, and it can be directly used for isolation and purification of penicillin acylase from the fermentation broth.