Modeling of Nitrite Utilization in E. coli Cells: Flux Analysis
Khlebodarova T.M., Kogai V.V., Akberdin I.R., Ri N.A., Fadeev S.I., Likhoshvai V.A.
Institute of Cytology and Genetics, SB RAS, Novosibirsk, 630090, Russia
Novosibirsk State University, Novosibirsk, 630090, Russia
Institute of Mathematics SB RAS, Novosibirsk, 630090, Russia
Abstract. The results of the model analysis are presented in the article. The model describes of nitrite utilization in E. coli cell under continuous cultivation in the chemostat. The model takes into account expression dynamics of nrf and nir operons encoding the structure of enzymes that participate in the nitrite' metabolism and transport. It has shown that the model adapted to the known data describes experimentally observed dynamics of the nitrite accumulation in the chemostat at millimolar concentrations of added nitrite without supplementary hypothesis. In the concentration area the permanent intracellular nitrite concentration which does not depend on its concentration in the growth environment is maintained in accordance to the model. To describe the kinetics of nitrite accumulation in the chemostat at micromolar concentrations of added nitrite the supplementary hypothesis about the existence of more high level of NrfA enzymatic activity than it observes in the genetic studies is required to be included in the model.
Key words: modeling, regulation of gene expression, Escherichia coli, anaerobic respiration.