摘要为了获得酶活力高且专一性强的非特异性核酸酶，满足核苷酸工业的生产和发展需求，本研究运用单因素实验法对培养含有非特异性核酸酶基因的基因工程大肠杆菌的培养基进行优化，从而获得培养该菌的最适培养基。本实验主要研究pH值、甘油、葡萄糖、蔗糖、酵母粉等碳源，氯化铵、蛋白胨等氮源，镁离子、钾离子、钠离子等无机盐离子对非特异性核酸酶活性及产量的影响。通过一系列的培养和检测，结果表明：最适pH为7，碳源中甘油、酵母粉为促进因素，葡萄糖，蔗糖为抑制因素，氮源中氯化铵表现为抑制，蛋白胨则表现为促进。无机盐离子中，钾离子、镁离子、钠离子、钙离子在一定浓度范围内对酶活的作用表现为促进，其他无机盐离子对酶活的影响则均表现为抑制。47718

Abstract   In order to obtain the non-specific nuclease of high enzymatic activity and specificity, meet nucleotide industrial production and development need, this research used the method of single factor experiment of culture medium to optimize the culture of gene engineering with nonspecific nuclease gene of Escherichia coli, thereby obtaining the optimal culture medium for culturing the bacteria. This experiment mainly study effect of pH value, glycerol, glucose, sucrose, yeast powder as carbon source, ammonium chloride, peptone as nitrogen source, magnesium ion, potassium ion, sodium ion and other inorganic salt ions on activity and yield of non-specific nuclease. Through a series of training and testing, the results show that the optimal pH is 7, glycerol, yeast powder, carbon source are promoting factors, and glucose, sucrose as inhibitory factors, ammonium chloride inhibited nitrogen source, peptone show promotion. Among the inorganic salt ions, role of potassium ion, magnesium ion, sodium ion, calcium ion activity of enzyme show promotion in certain concentration range, other inorganic salt ions on the enzymatic activity were inhibited.

毕业论文关键词：基因工程大肠杆菌；核酸酶；培养基优化；单因素实验法

Keyword: Genetically engineered Escherichia coli; Nuclease; Medium optimization; Single factor experiment

目   录

1 材料与方法 2

1.1实验材料 2

1.1.1菌种 2

1.1.2种子培养基及其组分 2

1.1.3发酵培养基及其组分 2

1.1.4试剂 2

1.1.5实验仪器 2

1.2实验方法 2

1.2.1菌种保藏 3

1.2.2 菌种活化、传代与接种 3

1.2.3摇瓶培养 3

1.2.3酶活测定 3

2 结果分析 4

2.1 pH对酶活的影响 4

2.2 碳源对酶活的影响 4

2.2.1葡萄糖和蔗糖对酶活的影响 4

2.2.2甘油对酶活的影响 4

2.2.3酵母粉对酶活的影响 5

2.3 氮源对酶活的影响 5

2.3.1氯化铵对酶活的影响 6

2.4无机盐离子对酶活的影响 6

2.4.1 Mn2+、Cu2+、Zn2+、Fe2+等对酶活的影响 6

2.4.2 K+对酶活的影响