• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biotechnology Progress >Serial C-13-based flux analysis of an L-phenylalanine-producing E-coli strain using the sensor reactor
【24h】

Serial C-13-based flux analysis of an L-phenylalanine-producing E-coli strain using the sensor reactor

机译：使用传感器反应器对产生L-苯丙氨酸的大肠杆菌菌株进行基于C-13的连续通量分析

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

With the aid of the recently developed Sensor reactor system, a series of three subsequent C-13 labeling experiments was performed mirroring the L-phenylalanine (L-Phe) production phase of a recombinant E. coli strain that was cultivated under industry-like conditions in a 300 L bioreactor. On the basis of the data from NMR labeling analysis, three subsequent flux patterns were successfully derived monitoring the L-Phe formation (luring an observation window from 14 to 23.3 h process time. Linear programming was performed to identify optimal flux patterns for L-Phe formation. Additionally, flux sensitivity analysis was used to identify the most promising metabolic engineering target. As a result, high rates of phosphoenolpyruvate (PEP) to pyruvate (PYR) conversion were identified as the most important reason for deterioration of the L-Phe/glucose yield from 20 to finally 11 mol %. Considering the characteristics of the enzyme kinetics involved, the working hypothesis was formulated that phosphoenolpyruvate synthase activity was increasingly hampered by rising oxaloacetate and 2-oxoglutarate concentrations, while at the same time pyruvate kinase activity arose due to activation by fructose 1,6-diphosphate. Hence, pps overexpression should be performed to optimize the existing production strain.
机译：借助最近开发的传感器反应器系统，进行了一系列的三个后续C-13标记实验，以反映在工业条件下培养的重组大肠杆菌菌株的L-苯丙氨酸（L-Phe）生产阶段。在300公升的生物反应器中根据NMR标记分析的数据，成功地获得了三个后续的通量模式，以监测L-Phe的形成（在14到23.3 h的处理时间中观察窗口的变化。进行线性编程，以确定L-Phe的最佳通量模式此外，通量敏感性分析被用来确定最有希望的代谢工程靶点，因此，高比例的磷酸烯醇丙酮酸（PEP）到丙酮酸（PYR）的转化被认为是导致L-Phe /降解的最重要原因。从20到11 mol％的葡萄糖产量，考虑到相关的酶动力学特性，提出了工作假设：草酰乙酸和2-氧戊二酸浓度的升高越来越阻碍磷酸烯醇丙酮酸合酶的活性，同时由于被1,6-二磷酸果糖激活，因此，应进行pps过表达以优化存在生产压力。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号