克雷伯氏杆菌发酵生产1,3-丙二醇的代谢通量优化分析  

Optimization of microbial production of 1,3-propanediol by Klebsiella pneumoniae under anaerobic and microaerobic conditions by metabolic flux analysis

作　　者：张青瑞[1] 修志龙[1] 曾安平 

机构地区：[1]大连理工大学环境与生命学院,辽宁大连116024 [2]德国国家生物技术中心,德国布伦瑞克d38106

出　　处：《化工学报》2006年第6期1403-1409,共7页CIESC Journal

基　　金：国家科技部"十五"科技攻关项目(子课题)(2004BA713B06-03);国家重点基础研究发展规划项目(2003CB716000).~~

摘　　要：以克雷伯氏杆菌为研究对象,系统研究了1,3-丙二醇厌氧和微氧代谢途径.采用代谢通量分析法建立了代谢通量平衡模型,通过线性规划对1,3-丙二醇厌氧和微氧发酵进行了优化分析,得到其最优代谢通量分布和最大理论得率,并分析了比生长速率、底物浓度以及乙醇生成速率、氧气消耗速率、呼吸商对1,3-丙二醇得率的影响.In this paper, a simplified metabolic network was constructed according to glycerol metabolism in Klebsiella pneumoniae under anaerobic and microaerobic conditions. A model of metabolic flux balance was set up by using metabolic flux analysis. The maximum theoretical yield of 1,3-propanediol （1,3-PD） to glycerol and the optimal flux distributions were obtained by using linear programming. In addition, the influences of specific growth rates, ethanol formation rates, molar fraction of NADH2 oxidized completely by molecular oxygen in TCA （tricarboxylie acid） cycle and respiratory quotient （RQ） on the maximum theoretical yield of 1,3-PD to glycerol were analyzed as well. The metabolic flux analysis showed that the maximum theoretical yield of 1,3-PD to glycerol could reach 0. 875 mol · mol^-1 rather than 0.75 mol · mol^-1 if all aeetyl-CoA entered into TCA cycle under mieoraerobie conditions instead of acetic acid pathway under anaerobic conditions. The theoretical yield of 1,3-PD decreased as the specific growth rate and the ethanol formation rate increased. There existed an optimum oxygen uptake rate and a RQ value at different specific growth rates.

关 键 词：1 3-丙二醇 代谢通量分析 线性规划 克雷伯氏杆菌 

分 类 号：Q591[生物学—生物化学]