Abstract
Colanic acid (CA) is a major exopolysaccharide synthesized by Escherichia coli that serves as a constituent of biofilm matrices. CA demonstrates potential applications in the food, cosmetics, and pharmaceutical industry. Moreover, l-fucose, a monomeric constituent of CA, exhibits various physiological activities, such as antitumor, anti-inflammatory, and skin-whitening. Here, the effects of genetic and environmental perturbations were investigated for improving CA production by E. coli. When rcsF, a positive regulator gene of CA synthesis, was expressed in E. coli ΔwaaF, a CA-producing strain constructed previously, the CA titer increased to 3051.2 mg/L as compared to 2052.8 mg/L observed with E. coli ΔwaaF. Among the environmental factors tested, namely, osmotic and oxidative stresses and pH, pH was a primary factor that significantly improved CA production. When the pH of the culture medium of E. coli ΔwaaF + rcsF was maintained at 7, the CA titer significantly increased to 4351.6 mg/L. The CA yield obtained with E. coli ΔwaaF + rcsF grown at pH 7 was 5180.4 mg CA/g dry cell weight, which is the highest yield of CA reported so far. This engineered E. coli system with optimization of environmental conditions can be employed for fast and economically-feasible production of CA.
Original language | English |
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Pages (from-to) | 4083-4096 |
Number of pages | 14 |
Journal | Applied Biochemistry and Biotechnology |
Volume | 193 |
Issue number | 12 |
DOIs | |
Publication status | Published - 2021 Dec |
Bibliographical note
Funding Information:This work was supported by the Mid-career Researcher Program through the National Research Foundation of Korea (2020R1A2B5B02002631) and the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry, and Fisheries, funded by the Ministry of Agriculture, Food, and Rural Affairs (321036051SB010).
Funding Information:
We acknowledge the facility support by the Institute of Biomedical and Food Safety at CJ Food Safety Hall, Korea University.
Publisher Copyright:
© 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Keywords
- Colanic acid
- Environmental perturbation
- Escherichia coli
- Exopolysaccharide
- rcsF
- waaF
ASJC Scopus subject areas
- Biotechnology
- Bioengineering
- Biochemistry
- Applied Microbiology and Biotechnology
- Molecular Biology