Back to Search
Start Over
Metabolic Engineering of Gas-Fermenting Clostridium ljungdahlii for Efficient Co-production of Isopropanol, 3-Hydroxybutyrate, and Ethanol.
- Source :
-
ACS synthetic biology [ACS Synth Biol] 2021 Oct 15; Vol. 10 (10), pp. 2628-2638. Date of Electronic Publication: 2021 Sep 22. - Publication Year :
- 2021
-
Abstract
- Rational design and modification of autotrophic bacteria to efficiently produce high-value chemicals and biofuels are crucial for establishing a sustainable and economically viable process for one-carbon (C1) source utilization, which, however, remains a challenge in metabolic engineering. In this study, autotrophic Clostridium ljungdahlii was metabolically engineered to efficiently co-produce three important bulk chemicals, isopropanol, 3-hydroxybutyrate (3-HB), and ethanol (together, IHE), using syngas (CO <subscript>2</subscript> /CO). An artificial isopropanol-producing pathway was first constructed and optimized in C. ljungdahlii to achieve an efficient production of isopropanol and an unexpected product, 3-HB. Based on this finding, an endogenous active dehydrogenase capable of converting acetoacetate to 3-HB was identified in C. ljungdahlii , thereby revealing an efficient 3-HB-producing pathway. The engineered strain was further optimized to reassimilate acetic acid and synthesize 3-HB by introducing heterologous functional genes. Finally, the best-performing strain was able to produce 13.4, 3.0, and 28.4 g/L of isopropanol, 3-HB, and ethanol, respectively, in continuous gas fermentation. Therefore, this work represents remarkable progress in microbial production of bulk chemicals using C1 gases.
Details
- Language :
- English
- ISSN :
- 2161-5063
- Volume :
- 10
- Issue :
- 10
- Database :
- MEDLINE
- Journal :
- ACS synthetic biology
- Publication Type :
- Academic Journal
- Accession number :
- 34549587
- Full Text :
- https://doi.org/10.1021/acssynbio.1c00235