AI Article Synopsis
- D-galactose can be converted into D-galactonate by engineered E. coli, which is beneficial for the polymer and cosmetic industries.
- Engineered E. coli expressing a specific galactose dehydrogenase showed significant D-galactonate production, especially when metabolic pathways for D-galactose and D-galactonate were blocked.
- By optimizing fermentation conditions, the study achieved a high concentration and yield of D-galactonate, highlighting the potential for industrial applications.
Article Abstract
D-galactose is an attractive substrate for bioconversion. Herein, Escherichia coli was metabolically engineered to convert D-galactose into D-galactonate, a valuable compound in the polymer and cosmetic industries. D-galactonate productions by engineered E. coli strains were observed in shake flask cultivations containing 2 g L(-1) D-galactose. Engineered E. coli expressing gld coding for galactose dehydrogenase from Pseudomonas syringae was able to produce 0.17 g L(-1) D-galactonate. Inherent metabolic pathways for assimilating both D-galactose and D-galactonate were blocked to enhance the production of D-galactonate. This approach finally led to a 7.3-fold increase with D-galactonate concentration of 1.24 g L(-1) and yield of 62.0 %. Batch fermentation in 20 g L(-1) D-galactose of E. coli ∆galK∆dgoK mutant expressing the gld resulted in 17.6 g L(-1) of D-galactonate accumulation and highest yield of 88.1 %. Metabolic engineering strategy developed in this study could be useful for industrial production of D-galactonate.
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| http://dx.doi.org/10.1007/s00449-013-1003-6 | DOI Listing |
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