摘要
产酸克雷伯氏菌Klebsiella oxytoca在利用葡萄糖产2,3-丁二醇过程中,底物葡萄糖主要有7种去处:转化为生物量;通过TCA循环支路产生CO2和H2O;通过各发酵支路分别产生2,3-丁二醇、乙醇、乙偶姻、乙酸以及乳酸等代谢产物。在拟稳态假设的基础上分别利用ATP及辅酶平衡建立了该过程中葡萄糖碳流在这7条支路之间分配的数学模型,着重分析了氧气供给量对发酵过程影响的相关机制;并应用实验数据回归了模型参数,将模型预测值与实验值进行了比较。结果表明,模型预测值与实验值较吻合,该模型能较好地反映Klebsiella oxytoca发酵产2,3-丁二醇过程中葡萄糖碳流的分配规律,对利用溶氧合理控制代谢流分布具有一定的指导意义。
During the fermentative production of 2,3-butanediol from glucose by Klebsiella oxytoca, the glucose that was taken up could be channelled through seven general pathways： assimilation to biomass, oxidation to carbon dioxide and water by respiration and conversion to 2,3-butanediol, ethanol, acetoin, acetic acid and lactic acid by fermentation. In this study, a model of glucose carbon flux distribution among the seven different pathways was established by assuming that the ATP and NAD （FAD） concentration in the bacteria cell were at a pseudo-steady-state level. Also, the influence of oxygen transfer rate on fermentation process was specially discussed. And the model parameters were regressed with the experimental data. The predictive values by the model were in good agreement with the experimental data. So the model could reflect the rule of glucose carbon flux distribution and thus guide the metabolic flux controlling based on the oxygen transfer rate during the fermentative production of 2,3 butanediol by Klet）siella o.rytoca.
出处
《化学与生物工程》
CAS
2007年第2期32-36,共5页
Chemistry & Bioengineering
基金
国家自然科学基金项目(20606018)
国家重点基础研究发展计划(973计划)(2007CB707805)
