Production of nonnatural straight chain amino acid 6-aminocaproate via an artificial recursive carbon-chain-extension cycle
Michael P. Torrens-Spence,
Posted 05 Mar 2019
bioRxiv DOI: 10.1101/568121 (published DOI: 10.1016/j.ymben.2019.06.009)
Posted 05 Mar 2019
Microbial bioplastics are present as promising and green alternatives to traditional petrochemical derived plastics. Nonnatural straight chain amino acids, especially 5-aminovalerate, 6-aminocaproate and 7-aminoheptanoate are potential monomers for the synthesis of bioplastics as their primary amine and carboxylic acid functional groups are ideal for polymerization. Previous pathways for 5-aminovalerate and 6-aminocaproate biosynthesis in microorganisms are derived from the L-lysine catabolism and citric acid cycle, respectively. Here we construct a novel biosynthetic route via artificial recursive carbon chain extension cycle for the simultaneous production of various chain length nonnatural amino acids. Overexpression of L-lysine α oxidase in Escherichia coli generates 2-keto-6-aminocaproate, the non-native substrate for the artificial recursive carbon chain extension cycle. The chain extended α-ketoacid is finally decarboxylated and oxidized by α-ketoacid decarboxylase and aldehyde dehydrogenase, respectively, to yield the nonnatural straight chain amino acid products. The recursive nature of this pathway used 2-keto-6-aminocaproate as substrate was first demonstrated in vitro with the simultaneous production of 99.16 mg/L of 5-aminovalerate, 46.96 mg/L of 6-aminocaproate and 4.78 mg/L of 7-aminoheptanoate after 8 h of enzyme catalysis. Furthermore, 2.179 g/L of nonnatural straight chain amino acids could be achieved by strain BL21(DE3) plus plasmids pIVC4 and pETaRKP, which simultaneously yields 2.15 g/L of 5-aminovalerate, 24.12 mg/L of 6-aminocaproate and 4.74 mg/L of 7-aminoheptanoate. The production of 6-aminocaproate and other nonnatural straight chain amino acids via the artificial recursive carbon chain extension cycle provides a potential strategy to produce other medium chain length acids with -NH2, -SCH3, -SOCH3, -SH, -COOH, -COH, -OH, etc. functional groups by carbon chain elongation.
- Downloaded 470 times
- Download rankings, all-time:
- Site-wide: 71,486
- In synthetic biology: 836
- Year to date:
- Site-wide: 103,632
- Since beginning of last month:
- Site-wide: 64,448
Downloads over time
Distribution of downloads per paper, site-wide
- 27 Nov 2020: The website and API now include results pulled from medRxiv as well as bioRxiv.
- 18 Dec 2019: We're pleased to announce PanLingua, a new tool that enables you to search for machine-translated bioRxiv preprints using more than 100 different languages.
- 21 May 2019: PLOS Biology has published a community page about Rxivist.org and its design.
- 10 May 2019: The paper analyzing the Rxivist dataset has been published at eLife.
- 1 Mar 2019: We now have summary statistics about bioRxiv downloads and submissions.
- 8 Feb 2019: Data from Altmetric is now available on the Rxivist details page for every preprint. Look for the "donut" under the download metrics.
- 30 Jan 2019: preLights has featured the Rxivist preprint and written about our findings.
- 22 Jan 2019: Nature just published an article about Rxivist and our data.
- 13 Jan 2019: The Rxivist preprint is live!