In vivo investigation of metabolic dynamics in Escherichia Coli K12 by evaluation of Rapid Sampling Experiments

摘要

The in vivo dynamics of the glycolysis and the pentose phosphate pathway (ppp) from Escherichia coli K12 were investigated with Rapid Sampling Experiments (RSE's) using an automated sampling device after a continuous culture grown under glucose limitation has been disturbed with a glucose pulse. For the interpretation of the experimental data 68 structured, kinetic models (model dimension: 9-10 ordinary differential equations (ODE's), 90-150 kinetic parameters) were formulated. 8 of the models based on 2 different topologies of the biochemical reaction network could represent the intracellular levels from 9 of 12 measured metabolites of the glycolysis and the ppp before and after the glucose pulse. The kinetic parameters identified were in the same order of magnitude as prepublished experimental observations. From the prediction of the flux distribution a maximal value of 0.8 could be derived for the split ratio into the glycolysis and the ppp.