产2,3-丁二醇高木糖耐性肺炎克雷伯氏菌转录组学分析与发酵优化  

Transcriptomics Analysis of High-xylose-tolerance Klebsiella pneumonia Strain and Optimization of Fermentation Conditions for 2,3-butanediol Production

作　　者：郭学武 张玉 关翔宇 倪晓丰 汪庆 陈叶福 肖冬光 GUO Xue-wu;ZHANG Yu;GUAN Xiang-yu;NI Xiao-feng;WANG Qing;CHEN Ye-fu;XIAO Dong-guang(Key Laboratory of lndustrial Ferrnentation Microbiology of Ministry of Edueation,College of Biotechnology,TianJin University of Science and Technology,Tianjin 300457;Tianjin Industrial Microbiology Key Lab,College of Biotechnology,Tianjin University of Science and Technology,Tianjin 300457)

机构地区：[1]天津科技大学生物工程学院工业发酵微生物教育部重点实验室,天津300457 [2]天津科技大学生物工程学院天津市工业微生物重点实验室,天津300457

出　　处：《生物技术通报》2018年第8期159-169,共11页Biotechnology Bulletin

基　　金：国家自然科学基金项目(21406168)

摘　　要：选育高木糖耐性肺炎克雷伯氏菌并对其进行转录组学分析与产2,3-丁二醇发酵条件的优化。首先通过适应性进化定向筛选出了具有高木糖耐受能力和2,3-丁二醇产量提高的肺炎克雷伯氏菌(KP2),然后对其进行转录组学分析与发酵条件优化。结果显示,筛选出的高木糖耐性的肺炎克雷伯氏菌木糖的转化率提高了174.5%,2,3-丁二醇的产量提高了227%。转录组分析结果表明亲本菌株KPG和KP2菌株差异表达基因中有242个基因上调和263个基因下调。Pathway分析表明,转录水平的变化主要表现在信号转导、碳水化合物代谢、能量代谢和其它物质代谢等。在1L反应器中,初始木糖浓度120 g/L时最优发酵条件为:温度35℃,转速230 r/min,通气量0.7 L/min,最适pH值5.9。在最优条件下,2,3-丁二醇产量达43.75 g/L,相比优化前提高了32.7%。本研究获得了高效利用木糖生产2,3-丁二醇的菌株,对表型变化产生的机理在分子水平上进行阐述,并得到了最优的发酵条件,结果可以为2,3-丁二醇的生物转化提供参考,对2,3-丁二醇的生物法生产具有一定的指导意义。This work is to breed a strain of Klebsiella pneumonia with high xylose tolerance, to analyze its transcriptomics, and to optimize the fermentation conditions of producing 2,3-butanediol （ 2,3-BD ） . Firstly, the adaptive evolution method was used to screen a K. pneumonia strain KP2 with high xylose tolerance and high yield of 2,3-BD. Then, the transcriptome analysis and the optimization of fermentation conditions were conducted. Results showed that the xylose conversion rate and 2,3-BD production by KP2 increased by 174.5% and 227%, respectively. The transcriptome analysis of parental strain KPG and KP2 demonstrated that 242 genes were up-regulated and 263 genes were down-regulated in KP2. The pathway analysis further revealed that the changes of transcripts mainly oecurred in signal transduction, carbohydrate metabolism, energy metabolism and other material metabolism. Under the initial concentration of xylose i20 g/L in 1 L reactor, the optimal fermentation conditions were as follows ： 35℃, 230 r/vain, 0.7 L/min （ aeration ）, and pH 5.9. Under this optimal condili（ms, lhe maximal production of 2,3-BD reached 43.9 g/L, which was improved by 33.3% compared to that before optimization. In sum, we successfully obtained the strain of producing 2,3-BD by efficiently using xylose, the mechanism of phenotypic change was expounded at the molecular level, and the optimal fermentation conditions were determined. The result may provide reference for the production of 2,3-BD, and has a certain guiding significance for the biological production of 2,3-BD.

关 键 词：适应性进化 肺炎克雷伯氏菌 转录组学分析 响应面优化 2 3-丁二醇 

分 类 号：TQ923[轻工技术与工程—发酵工程] Q933[生物学—微生物学]