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Combining De Ley-Doudoroff and methylerythritol phosphate pathways for enhanced isoprene biosynthesis from D-galactose.
- Source :
-
Bioprocess and biosystems engineering [Bioprocess Biosyst Eng] 2014 Dec; Vol. 37 (12), pp. 2505-13. Date of Electronic Publication: 2014 Jun 14. - Publication Year :
- 2014
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Abstract
- An engineered Escherichia coli strain was developed for enhanced isoprene production using D-galactose as substrate. Isoprene is a valuable compound that can be biosynthetically produced from pyruvate and glyceraldehyde-3-phosphate (G3P) through the methylerythritol phosphate pathway (MEP). The Leloir and De Ley-Doudoroff (DD) pathways are known existing routes in E. coli that can supply the MEP precursors from D-galactose. The DD pathway was selected as it is capable of supplying equimolar amounts of pyruvate and G3P simultaneously. To exclusively direct D-galactose toward the DD pathway, an E. coli ΔgalK strain with blocked Leloir pathway was used as the host. To obtain a fully functional DD pathway, a dehydrogenase encoding gene (gld) was recruited from Pseudomonas syringae to catalyze D-galactose conversion to D-galactonate. Overexpressions of endogenous genes known as MEP bottlenecks, and a heterologous gene, were conducted to enhance and enable isoprene production, respectively. Growth test confirmed a functional DD pathway concomitant with equimolar generation of pyruvate and G3P, in contrast to the wild-type strain where G3P was limiting. Finally, the engineered strain with combined DD-MEP pathway exhibited the highest isoprene production. This suggests that the equimolar pyruvate and G3P pools resulted in a more efficient carbon flux toward isoprene production. This strategy provides a new platform for developing improved isoprenoid producing strains through the combined DD-MEP pathway.
- Subjects :
- Butadienes chemistry
Carbon chemistry
Catalysis
DNA chemistry
DNA Primers chemistry
Erythritol chemistry
Glyceraldehyde 3-Phosphate chemistry
Hemiterpenes chemistry
Pentanes chemistry
Phosphates metabolism
Plasmids metabolism
Pseudomonas syringae enzymology
Pyruvic Acid chemistry
Biotechnology methods
Erythritol analogs & derivatives
Escherichia coli metabolism
Galactose chemistry
Hemiterpenes biosynthesis
Sugar Phosphates chemistry
Subjects
Details
- Language :
- English
- ISSN :
- 1615-7605
- Volume :
- 37
- Issue :
- 12
- Database :
- MEDLINE
- Journal :
- Bioprocess and biosystems engineering
- Publication Type :
- Academic Journal
- Accession number :
- 24928200
- Full Text :
- https://doi.org/10.1007/s00449-014-1228-z