摘要
以地衣芽孢杆菌（ＢａｃｉｌｕｓＬｉｃｈｅｎｉｆｏｒｍｉｓ）５３号菌为出发菌株，在原生质形成和再生的最佳条件下制备原生质体，并对原生质体进行了多次诱变处理，从大量突变株进行筛选最终获得了高产、稳定、耐热的碱性蛋白酶产生菌株５３－Ｇ３８－６，产酶活力由１１０４Ｕ／ｍｌ提高到２２０８０Ｕ／ｍｌ．该诱变株最适产酶条件为：培养基由质量分数（ｗ／％）为胰蛋白胨１，酵母膏０．５，玉米粉５，Ｎａ２ＨＰＯ４１２Ｈ２Ｏ０．４，ＫＨ２ＰＯ４０．０３，Ｎａ２ＣＯ３０．１组成，ｐＨ自然，培养温度４２℃，培养时间４４～４８ｈ，ｗ／％为０．２的ＣａＣＯ３可提高酶的产量．酶作用的最适条件：６２℃，ｐＨ１０．０。
Under the optimal conditions for protoplasts formation and regeneration, the protoplasts from the primitive strain Bacillus Licheniformis 53 A 6 were prepared. After many times of mutagenetic treatment of protoplasts of strain 53 and selections from a lot of mutants obtained, a mutant 53 G 38 6 was finally obtained with properties of high output, stable and thermo resistant alkaline protease. The enzyme activity of the mutant rose up to 22080 U/ml as compared with 1104 U/ml of th original. The fermentation medium consisted of w/% 1% Tryptone, 0.5% Yeast extract, 5% corn, 0.4% Na 2HPO 4·12H 2O, 0.03% KH 2PO 4, 0.1% Na 2CO 3. The high yield strain produced maximal alkaline protease after growing at 42℃ for 44～48h on a rotary shaker. The optimum temperature and pH for the protease activity production are 62℃ and 10.0 respectively and stable at pH 9～10.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
1997年第2期72-78,共7页
Journal of Lanzhou University(Natural Sciences)
基金
甘肃省自然科学基金
