Dataset Information

Engineering Escherichia coli to Utilize Erythritol as Sole Carbon Source.

ABSTRACT: Erythritol, one of the natural sugar alcohols, is widely used as a sugar substitute sweetener in food industries. Humans themselves are not able to catabolize erythritol and their gut microbes lack related catabolic pathways either to metabolize erythritol. Here, Escherichia coli (E. coli) is engineered to utilize erythritol as sole carbon source aiming for defined applications. First, the erythritol metabolic gene cluster is isolated and the erythritol-binding transcriptional repressor and its DNA-binding site are experimentally characterized. Transcriptome analysis suggests that carbohydrate metabolism-related genes in the engineered E. coli are overall upregulated. In particular, the enzymes of transaldolase (talA and talB) and transketolase (tktA and tktB) are notably overexpressed (e.g., the expression of tktB is improved by nearly sixfold). By overexpression of the four genes, cell growth can be increased as high as three times compared to the cell cultivation without overexpression. Finally, engineered E. coli strains can be used as a living detector to distinguish erythritol-containing soda soft drinks and can grow in the simulated intestinal fluid supplemented with erythritol. This work is expected to inspire the engineering of more hosts to respond and utilize erythritol for broad applications in metabolic engineering, synthetic biology, and biomedical engineering.

SUBMITTER: Ba F

PROVIDER: S-EPMC10190533 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Engineering Escherichia coli to Utilize Erythritol as Sole Carbon Source.

Ba Fang F Ji Xiangyang X Huang Shuhui S Zhang Yufei Y Liu Wan-Qiu WQ Liu Yifan Y Ling Shengjie S Li Jian J

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20230320 14

Erythritol, one of the natural sugar alcohols, is widely used as a sugar substitute sweetener in food industries. Humans themselves are not able to catabolize erythritol and their gut microbes lack related catabolic pathways either to metabolize erythritol. Here, Escherichia coli (E. coli) is engineered to utilize erythritol as sole carbon source aiming for defined applications. First, the erythritol metabolic gene cluster is isolated and the erythritol-binding transcriptional repressor and its ...[more]

PMID: 36938858

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Project description:The increasing demand for non-food competitive carbon sources such as methanol for biotechnology has brought methanol-utilizing bacteria, so-called methylotrophs, to focus. The product spectrum of natural methylotrophs and their genetic accessibility is limited and as an alternative approach, the introduction of methylotrophic metabolism into a biotechnologically well-established organism, such as Escherichia coli, represents a promising concept. By performing long-term evolution over 600 days, we obtained an E. coli strain that is able to grow on methanol as its sole carbon source at rates comparable to natural methylotrophic organisms. We confirmed that the strain forms its entire biomass from methanol. Furthermore, we sequenced the genome of the evolved strain and compared it to the genome of its ancestor. Intriguingly, we found several hundreds of mutations targeting genes of various functions, such as catalysis and regulation. Like the comparison of the genome before and after evolution, the investigation of the proteome would be of high interest. Proteomics would reveal the consequences of the regulatory mutations found in the genome and provide an overall picture of the adaptations by the cell enabling it to grow on methanol. The increasing demand for non-food competitive carbon sources such as methanol for biotechnology has brought methanol-utilizing bacteria, so-called methylotrophs, to focus. The product spectrum of natural methylotrophs and their genetic accessibility is limited and as an alternative approach, the introduction of methylotrophic metabolism into a biotechnologically well-established organism, such as Escherichia coli, represents a promising concept. By performing long-term evolution over 600 days, we obtained an E. coli strain that is able to grow on methanol as its sole carbon source at rates comparable to natural methylotrophic organisms. We confirmed that the strain forms its entire biomass from methanol. Furthermore, we sequenced the genome of the evolved strain and compared it to the genome of its ancestor. Intriguingly, we found several hundreds of mutations targeting genes of various functions, such as catalysis and regulation. Like the comparison of the genome before and after evolution, the investigation of the proteome would be of high interest. Proteomics would reveal the consequences of the regulatory mutations found in the genome and provide an overall picture of the adaptations by the cell enabling it to grow on methanol.

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Dataset Information

Engineering Escherichia coli to Utilize Erythritol as Sole Carbon Source.

Publications

Engineering Escherichia coli to Utilize Erythritol as Sole Carbon Source.

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