Simulation of Dynamic Behavior of Glucose- and Tryptophan-Grown Escherichia coli Using Constraint-Based Metabolic Models with a Hierarchical Regulatory Network

  • Lee Sung-Gun (Department of Chemical Engineering, College of Engineering, Pusan National University) ;
  • Kim Yu-Jin (Department of Chemical Engineering, College of Engineering, Pusan National University) ;
  • Han Sang-Il (Department of Chemical Engineering, College of Engineering, Pusan National University) ;
  • Oh You-Kwan (Biomass Research Team, Korea Institute of Energy Research) ;
  • Park Sung-Hoon (Department of Chemical Engineering, College of Engineering, Pusan National University) ;
  • Kim Young-Han (Department of Chemical Engineering, Dong-A University) ;
  • Hwang Kyu-Suk (Department of Chemical Engineering, College of Engineering, Pusan National University)
  • 발행 : 2006.06.01

초록

We earlier suggested a hierarchical regulatory network using defined modeling symbols and weights in order to improve the flux balance analysis (FBA) with regulatory events that were represented by if-then rules and Boolean logic. In the present study, the simulation results of the models, which were developed and improved from the previou model by incorporating a hierarchical regulatory network into the FBA, were compared with the experimental outcome of an aerobic batch growth of E. coli on glucose and tryptophan. From the experimental result, a diauxic growth curve was observed, reflecting growth resumption, when tryptophan was used as an alternativee after the supply of glucose was exhausted. The model parameters, the initial concentration of substrates (0.92 mM glucose and 1 mM tryptophan), cell density (0.0086 g biomass/1), the maximal uptake rates of substrates (5.4 mmol glucose/g DCW h and 1.32 mmol tryptophan/g DCW h), and lag time (0.32 h) were derived from the experimental data for more accurate prediction. The simulation results agreed with the experimental outcome of the temporal profiles of cell density and glucose, and tryptophan concentrations.

키워드

참고문헌

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