论文标题:鸟苷工程菌的构建及其发酵条件的初步研究
The Construction of an Guanosine-Producing Engineering Strain and the Primary Study on the Fermentation Conditons
论文作者
论文导师 陈宁,论文学位 硕士,论文专业 发酵工程
论文单位 天津科技大学,点击次数 77,论文页数 75页File Size3086K
2005-01-01论文网 http://www.lw23.com/lunwen_613078047/
Guanosine;Bacillus subtilis;fermentation;gene engineering Kinetics
本文以代谢控制发酵理论为指导,进行了鸟苷工程菌的构建及其发酵条件的初步研究。主要研究内容和结果如下: 1.建立了发酵液中鸟苷定量测定的方法——离子交换法,对其最佳分离条件进行了研究,并与纸层析法进行比较,发现该方法准确度和精确度比纸层析方法高,可用于简单条件下对鸟苷发酵液中目的产物的测定。 2.利用质粒DNA的原生质体转化法,将工程菌Q2901中携带有磺胺胍抗性基因的重组质粒pUBLW2导入鸟苷产生菌TA208中,构建出鸟苷工程菌株TA424(pUBLW2/Km~r+SG~r)。 3.研究了鸟苷工程菌TA424摇瓶发酵生产鸟苷的最佳条件。通过均匀设计和模式识别方法分别研究了鸟苷种子和发酵培养基的最佳配比。在最佳条件下,摇瓶分批发酵产鸟苷24.8g/L。 4.利用5升发酵罐上的鸟苷分批发酵实验数据,基于构建的数学模型,采用MATLAB数值应用软件进行非线性规划建立了菌体生长、产物生成和底物消耗动力学模型。该模型能够较好地反映鸟苷分批发酵过程。
According to the theory of metabolic control fermentation, the dissertation focuses on the the construction of an guanosine-producing engineering strain and the primary study on the fermentation conditions. The main research contents and results are as follows:1. The method of ion exchange chromatography was defined to determinate guanosine concentration quantitatively in the fermentation broth. The separation conditions of this method was optimized and compared with paper chromatography method. Both accuracy and precision are better than that of paper chromatography.2. By means of protoplast transformation, the plasmid pUBLW2 containing SG~r gene was transformed to the recipient — the guanosine-producing strain Bacillus subtilis TA208. The engineering strain TA424(pUBLW2/Km~r+SG~r) with higher resistence was finally obtained.3. The batch fermentation conditions of the transformant TA424(pUBLW2/Km~r+SG~r) in shake flask was studied in this dissertation. The proportions of seed medium and fermentation medium were optimized by uniform design experiment and pattern recognition . Under the optimum condition, strain TA424(pUBLW2/Km~r+SG~r) could produce guanosine 24.8g/L by shaking flask batch fermentation.4. The guanosine batch fermentation kinetics were studied based on the datas got from 5-liter fermentor fermentation. Three kinetic models were constructed which could perfectly reflect the growth、 product formation and substrate consumption in the process of batch fermentation.
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