青霉素酶发酵液的预处理和酶学特性

Studies on the pretreatment of fermentation broth and the characterization of penicillinase

研究了在发酵液中添加絮凝剂对发酵液进行预处理,对蜡状芽孢杆菌(Bacillus cereus)产生青霉素酶的影响与酶学特性。实验结果表明,发酵液膜处理的难易程度与芽孢释放程度成正相关,在发酵液中添加0.02 g/mL自制絮凝剂进行预处理,过滤效率提高10倍,而酶活损失仅5%;酶学特性研究结果表明,该酶最佳反应温度55℃时,酶的最适反应pH值7.0,金属离子锌、锰、镁对酶有激活作用,其浓度为0.25 mol/L;酶热稳定性研究结果表明,在75℃下保温30 m in时,酶活损失85%。该酶在过量青霉素底物下,酶促反应为0级反应。

The pretreatment of fermentation broth and the characterization of penicillinase are studied. The results showed that, the treatment of membrane for fermentation broth were related to the lysis and release of Bacillus cereus spore. When adding flocculant 0. 03 g/mL to fermemtation broth, the treatment of membrane was very easy,but the loss of penicillinase activity was 5%. The optimum conditons for the enzymatic reaction were as follaws, the temperature at 55 ℃, and pH 7.0. The enzyme was activated by Zinc, Manganese and Magnesium with 0. 25 mol/L, when the enzyme remaining at 75 ℃ for 30 min, the activity of penicillinase lost 85%. The reaction showed 0 order with overfeeding of substrate-penicillin .