【作者】 刘晓辉；

【导师】 熊宗贵；

【作者基本信息】 沈阳药科大学 ， 微生物与生化药学， 2002， 硕士

【摘要】 以氨甲酰妥布霉素产生菌S.tenebrarius UVS-51为出发菌株，通过UV和NTG等诱变剂反复处理，再进一步结合耐自身代谢物的驯育，运用混菌生检法初筛，获得两株高产稳定变株NS-81和NT-26。这两株菌的摇瓶发酵效价分别比UVS-51菌株提高53％和77％，经薄层层析检验，该两变株的产物仍为单一氨甲酰妥布霉素。 本文还对这三株氨甲酰妥布霉素产生菌的遗传稳定性、发酵工艺和培养条件进行了考察研究。结果表明：斜面生长10天左右最为合适；成熟的孢子斜面在4℃冰箱中放置一周左右，发酵结果最好；以10％接种量，250mL摇瓶中装量40mL为最佳发酵条件。同时测定了发酵代谢曲线。 实验过程中，由于采用混菌生检法作为初筛模型，大大缩短了实验周期，减小了工作量；再引入循环诱变的思路，有效地提高了诱变育种的工作效率，能在较短时间内选育到理想变株。更多还原

【Abstract】 By treating original s, tenebrarius UVS-51 producing only carbamoyl tobramycin with UV and NTG as mutagens and the tolerant treatment was used, two stable mutants were isolated through the cyclic screening and mixed cultures assay method. The titers of antibiotic produced by the two mutants NS-81 and NT-26 in shaken flasks were 53% and 77% higher than that of the control respectively. They were all identified to be a single component producer of tobramycin by means of TLC.Studies were carried out on genetic stability, fermentation process and cultural characters of the three strains in this paper. Optimum time that the mutants were grown on slant medium were 10d, mature spores were placed in refrigerator for about a week, 10% of inoculum size and 40ml medium in 250ml flask were proved to be the best fermentation condition. At the same time, metabolic changes were observed too.Because the idea of cyclic mutation and the method of mixed cultures assay were introduced in this test, the cycle of the test was shortened widely and the efficiency of mutation breeding was improved effectively. The good mutants could be obtained in a short time.更多还原