Improving olefin tolerance and production in E. coli using native and evolved AcrB
| Autor: | Melissa Nhan, Aindrila Mukhopadhyay, Angélique Chanal, Kathleen Hirano, Eric G. Luning, Florence Mingardon, Camille Clement |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Models
Molecular Protein Structure Bioengineering Bacterial growth Biology Alkenes medicine.disease_cause Protein Engineering Applied Microbiology and Biotechnology Bioplastic host engineering Styrene chemistry.chemical_compound Industrial Microbiology Models medicine Escherichia coli Point Mutation olefin production directed evolution Escherichia coli Proteins Molecular Protein engineering Articles Industrial microbiology Directed evolution Protein Structure Tertiary Biochemistry chemistry Efflux Multidrug Resistance-Associated Proteins solvent tolerance Tertiary Biotechnology |
| Zdroj: | Biotechnology and bioengineering, vol 112, iss 5 Biotechnology and Bioengineering Mingardon, F; Clement, C; Hirano, K; Nhan, M; Luning, EG; Chanal, A; et al.(2015). Improving olefin tolerance and production in E. coli using native and evolved AcrB. Biotechnology and Bioengineering, 112(5), 879-888. doi: 10.1002/bit.25511. Lawrence Berkeley National Laboratory: Retrieved from: http://www.escholarship.org/uc/item/4v23p4x7 |
| Popis: | Microorganisms can be engineered for the production of chemicals utilized in the polymer industry. However many such target compounds inhibit microbial growth and might correspondingly limit production levels. Here, we focus on compounds that are precursors to bioplastics, specifically styrene and representative alpha-olefins; 1-hexene, 1-octene, and 1-nonene. We evaluated the role of the Escherichia coli efflux pump, AcrAB-TolC, in enhancing tolerance towards these olefin compounds. AcrAB-TolC is involved in the tolerance towards all four compounds in E. coli. Both styrene and 1-hexene are highly toxic to E. coli. Styrene is a model plastics precursor with an established route for production in E. coli (McKenna and Nielsen, 2011). Though our data indicates that AcrAB-TolC is important for its optimal production, we observed a strong negative selection against the production of styrene in E. coli. Thus we used 1-hexene as a model compound to implement a directed evolution strategy to further improve the tolerance phenotype towards this alpha-olefin. We focused on optimization of AcrB, the inner membrane domain known to be responsible for substrate binding, and found several mutations (A279T, Q584R, F617L, L822P, F927S, and F1033Y) that resulted in improved tolerance. Several of these mutations could also be combined in a synergistic manner. Our study shows efflux pumps to be an important mechanism in host engineering for olefins, and one that can be further improved using strategies such as directed evolution, to increase tolerance and potentially production. Biotechnol. Bioeng. 2015;112: 879–888. © 2015 The Authors. Biotechnology and Bioengineering Published by John Wiley & Periodicals, Inc. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|