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Upstream development of Escherichia coli fermentation process with PhoA promoter using design of experiments (DoE).

ABSTRACT: In this work, a fed-batch fermentation development was performed with recombinant E. coli carrying the PhoA promoter system. The phosphate concentrations tested for this PhoA strain, 2.79 mM to 86.4 mM, were beyond the concentrations previously evaluated for cell growth and product titer. The results from the scouting work was used for design of experiments (DoE) where a range of phosphate levels from 27.1 mM to 86.4 mM was simultaneously evaluated with temperature, pH and DO set points. Definitive screening was used to evaluate these parameters simultaneously and the results indicate that fermentation temperature and phosphate content are the major contributors of product titer. The other factors tested such as pH had a minimal effect and DO had no impact on product titer.

SUBMITTER: Agbogbo FK

PROVIDER: S-EPMC7658055 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Upstream development of Escherichia coli fermentation process with PhoA promoter using design of experiments (DoE).

Agbogbo Frank K FK Ramsey Phil P George Renija R Joy Jobin J Srivastava Shikha S Huang Mian M McCool Jesse J

Journal of industrial microbiology & biotechnology 20200825 9-10

In this work, a fed-batch fermentation development was performed with recombinant E. coli carrying the PhoA promoter system. The phosphate concentrations tested for this PhoA strain, 2.79 mM to 86.4 mM, were beyond the concentrations previously evaluated for cell growth and product titer. The results from the scouting work was used for design of experiments (DoE) where a range of phosphate levels from 27.1 mM to 86.4 mM was simultaneously evaluated with temperature, pH and DO set points. Definit ...[more]

PMID: 32844325

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