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Engineering Escherichia coli to grow constitutively on D-xylose using the carbon-efficient Weimberg pathway
Bio-production of fuels and chemicals from lignocellulosic C5 sugars usually requires the use of the pentose phosphate pathway (PPP) to produce pyruvate. Unfortunately, the oxidation of pyruvate to acetyl-coenzyme A results in the loss of 33 % of the carbon as CO(2), to the detriment of sustainabili...
Autores principales: | , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Microbiology Society
2018
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5882109/ https://www.ncbi.nlm.nih.gov/pubmed/29458683 http://dx.doi.org/10.1099/mic.0.000611 |
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author | Rossoni, Luca Carr, Reuben Baxter, Scott Cortis, Roxann Thorpe, Thomas Eastham, Graham Stephens, Gill |
author_facet | Rossoni, Luca Carr, Reuben Baxter, Scott Cortis, Roxann Thorpe, Thomas Eastham, Graham Stephens, Gill |
author_sort | Rossoni, Luca |
collection | PubMed |
description | Bio-production of fuels and chemicals from lignocellulosic C5 sugars usually requires the use of the pentose phosphate pathway (PPP) to produce pyruvate. Unfortunately, the oxidation of pyruvate to acetyl-coenzyme A results in the loss of 33 % of the carbon as CO(2), to the detriment of sustainability and process economics. To improve atom efficiency, we engineered Escherichia coli to utilize d-xylose constitutively using the Weimberg pathway, to allow direct production of 2-oxoglutarate without CO(2) loss. After confirming enzyme expression in vitro, the pathway expression was optimized in vivo using a combinatorial approach, by screening a range of constitutive promoters whilst systematically varying the gene order. A PPP-deficient (ΔxylAB), 2-oxoglutarate auxotroph (Δicd) was used as the host strain, so that growth on d-xylose depended on the expression of the Weimberg pathway, and variants expressing Caulobacter crescentus xylXAB could be selected on minimal agar plates. The strains were isolated and high-throughput measurement of the growth rates on d-xylose was used to identify the fastest growing variant. This strain contained the pL promoter, with C. crescentus xylA at the first position in the synthetic operon, and grew at 42 % of the rate on d-xylose compared to wild-type E. coli using the PPP. Remarkably, the biomass yield was improved by 53.5 % compared with the wild-type upon restoration of icd activity. Therefore, the strain grows efficiently and constitutively on d-xylose, and offers great potential for use as a new host strain to engineer carbon-efficient production of fuels and chemicals via the Weimberg pathway. |
format | Online Article Text |
id | pubmed-5882109 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2018 |
publisher | Microbiology Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-58821092018-04-05 Engineering Escherichia coli to grow constitutively on D-xylose using the carbon-efficient Weimberg pathway Rossoni, Luca Carr, Reuben Baxter, Scott Cortis, Roxann Thorpe, Thomas Eastham, Graham Stephens, Gill Microbiology (Reading) Biotechnology Bio-production of fuels and chemicals from lignocellulosic C5 sugars usually requires the use of the pentose phosphate pathway (PPP) to produce pyruvate. Unfortunately, the oxidation of pyruvate to acetyl-coenzyme A results in the loss of 33 % of the carbon as CO(2), to the detriment of sustainability and process economics. To improve atom efficiency, we engineered Escherichia coli to utilize d-xylose constitutively using the Weimberg pathway, to allow direct production of 2-oxoglutarate without CO(2) loss. After confirming enzyme expression in vitro, the pathway expression was optimized in vivo using a combinatorial approach, by screening a range of constitutive promoters whilst systematically varying the gene order. A PPP-deficient (ΔxylAB), 2-oxoglutarate auxotroph (Δicd) was used as the host strain, so that growth on d-xylose depended on the expression of the Weimberg pathway, and variants expressing Caulobacter crescentus xylXAB could be selected on minimal agar plates. The strains were isolated and high-throughput measurement of the growth rates on d-xylose was used to identify the fastest growing variant. This strain contained the pL promoter, with C. crescentus xylA at the first position in the synthetic operon, and grew at 42 % of the rate on d-xylose compared to wild-type E. coli using the PPP. Remarkably, the biomass yield was improved by 53.5 % compared with the wild-type upon restoration of icd activity. Therefore, the strain grows efficiently and constitutively on d-xylose, and offers great potential for use as a new host strain to engineer carbon-efficient production of fuels and chemicals via the Weimberg pathway. Microbiology Society 2018-03 2018-02-05 /pmc/articles/PMC5882109/ /pubmed/29458683 http://dx.doi.org/10.1099/mic.0.000611 Text en © 2018 The Authors http://creativecommons.org/licenses/by/4.0/ This is an open access article under the terms of theCreative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited. |
spellingShingle | Biotechnology Rossoni, Luca Carr, Reuben Baxter, Scott Cortis, Roxann Thorpe, Thomas Eastham, Graham Stephens, Gill Engineering Escherichia coli to grow constitutively on D-xylose using the carbon-efficient Weimberg pathway |
title | Engineering Escherichia coli to grow constitutively on D-xylose using the carbon-efficient Weimberg pathway |
title_full | Engineering Escherichia coli to grow constitutively on D-xylose using the carbon-efficient Weimberg pathway |
title_fullStr | Engineering Escherichia coli to grow constitutively on D-xylose using the carbon-efficient Weimberg pathway |
title_full_unstemmed | Engineering Escherichia coli to grow constitutively on D-xylose using the carbon-efficient Weimberg pathway |
title_short | Engineering Escherichia coli to grow constitutively on D-xylose using the carbon-efficient Weimberg pathway |
title_sort | engineering escherichia coli to grow constitutively on d-xylose using the carbon-efficient weimberg pathway |
topic | Biotechnology |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5882109/ https://www.ncbi.nlm.nih.gov/pubmed/29458683 http://dx.doi.org/10.1099/mic.0.000611 |
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