Modeling of the pyruvate production with Escherichia coli in a fed-batch bioreactor

• Published in: Bioprocess and biosystems engineering Vol. 26; no. 4; pp. 249 - 258
• Main Authors: Zelić, B, Vasić-Racki, D, Wandrey, C, Takors, R
• Format: Journal Article
• Language: English
• Published: Germany Springer Nature B.V 01-07-2004
• Subjects: Bacteria; Batch processes; Bioreactors; Bioreactors - microbiology; Carbon sources; Cell Culture Techniques - methods; Cell Proliferation; Computer Simulation; E coli; Escherichia coli - physiology; Fermentation; Glucose - metabolism; Microbiology; Models, Biological; Pyruvic Acid - metabolism
• ISSN: 1615-7591; 1615-7605
• DOI: 10.1007/s00449-004-0358-0

A family of 10 competing, unstructured models has been developed to model cell growth, substrate consumption, and product formation of the pyruvate producing strain Escherichia coli YYC202 ldhA::Kan strain used in fed-batch processes. The strain is completely blocked in its ability to convert pyruvate into acetyl-CoA or acetate (using glucose as the carbon source) resulting in an acetate auxotrophy during growth in glucose minimal medium. Parameter estimation was carried out using data from fed-batch fermentation performed at constant glucose feed rates of q(VG)=10 mL h(-1). Acetate was fed according to the previously developed feeding strategy. While the model identification was realized by least-square fit, the model discrimination was based on the model selection criterion (MSC). The validation of model parameters was performed applying data from two different fed-batch experiments with glucose feed rate q(VG)=20 and 30 mL h(-1), respectively. Consequently, the most suitable model was identified that reflected the pyruvate and biomass curves adequately by considering a pyruvate inhibited growth (Jerusalimsky approach) and pyruvate inhibited product formation (described by modified Luedeking-Piret/Levenspiel term).