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Kim YC, Yoo HW, Park BG, Sarak S, Hahn JS, Kim BG, Yun H. One-Pot Biocatalytic Route from Alkanes to α,ω-Diamines by Whole-Cell Consortia of Engineered Yarrowia lipolytica and Escherichia coli. ACS Synth Biol 2024. [PMID: 38912892 DOI: 10.1021/acssynbio.4c00273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
Metabolically engineered microbial consortia can contribute as a promising production platform for the supply of polyamide monomers. To date, the biosynthesis of long-chain α,ω-diamines from n-alkanes is challenging because of the inert nature of n-alkanes and the complexity of the overall synthesis pathway. We combined an engineered Yarrowia lipolytica module with Escherichia coli modules to obtain a mixed strain microbial consortium that could catalyze an efficient biotransformation of n-alkanes into corresponding α,ω-diamines. The engineered Y. lipolytica strain was constructed (YALI10) wherein the two genes responsible for β-oxidation and the five genes responsible for the overoxidation of fatty aldehydes were deleted. This newly constructed YALI10 strain expressing transaminase (TA) could produce 0.2 mM 1,12-dodecanediamine (40.1 mg/L) from 10 mM n-dodecane. The microbial consortia comprising engineered Y. lipolytica strains for the oxidation of n-alkanes (OM) and an E. coli amination module (AM) expressing an aldehyde reductase (AHR) and transaminase (TA) improved the production of 1,12-diamine up to 1.95 mM (391 mg/L) from 10 mM n-dodecane. Finally, combining the E. coli reduction module (RM) expressing a carboxylic acid reductase (CAR) and an sfp phosphopantetheinyl transferase with OM and AM further improved the production of 1,12-diamine by catalyzing the reduction of undesired 1,12-diacids into 1,12-diols, which further undergo amination to give 1,12-diamine as the target product. This newly constructed mixed strain consortium comprising three modules in one pot gave 4.1 mM (41%; 816 mg/L) 1,12-diaminododecane from 10 mM n-dodecane. The whole-cell consortia reported herein present an elegant "greener" alternative for the biosynthesis of various α,ω-diamines (C8, C10, C12, and C14) from corresponding n-alkanes.
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Affiliation(s)
- Ye Chan Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, South Korea
| | - Hee-Wang Yoo
- Manufacfuring development, Pyeongtaek plant, Hanmi Pharm. Co., Pyeontaek 17118, South Korea
| | - Beom Gi Park
- CutisBio Co., Ltd., 8F Apgujeong B/D, 842 Nonhyeon-ro, Gangnam-gu, Seoul 08826, South Korea
| | - Sharad Sarak
- Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Saint Paul campus, Saint Paul, Minnesota 55108, United States of America
| | - Ji-Sook Hahn
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, South Korea
| | - Byung-Gee Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, South Korea
| | - Hyungdon Yun
- Department of Systems Biotechnology, Konkuk University, Seoul 05029, South Korea
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Gu S, Zhu F, Zhang L, Wen J. Mid-Long Chain Dicarboxylic Acid Production via Systems Metabolic Engineering: Progress and Prospects. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:5555-5573. [PMID: 38442481 DOI: 10.1021/acs.jafc.4c00002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
Mid-to-long-chain dicarboxylic acids (DCAi, i ≥ 6) are organic compounds in which two carboxylic acid functional groups are present at the terminal position of the carbon chain. These acids find important applications as structural components and intermediates across various industrial sectors, including organic compound synthesis, food production, pharmaceutical development, and agricultural manufacturing. However, conventional petroleum-based DCA production methods cause environmental pollution, making sustainable development challenging. Hence, the demand for eco-friendly processes and renewable raw materials for DCA production is rising. Owing to advances in systems metabolic engineering, new tools from systems biology, synthetic biology, and evolutionary engineering can now be used for the sustainable production of energy-dense biofuels. Here, we explore systems metabolic engineering strategies for DCA synthesis in various chassis via the conversion of different raw materials into mid-to-long-chain DCAs. Subsequently, we discuss the future challenges in this field and propose synthetic biology approaches for the efficient production and successful commercialization of these acids.
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Affiliation(s)
- Shanna Gu
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072,China
- Frontiers Science Center for Synthetic Biology (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072,China
- SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co., Ltd, Dalian 116045, China
| | - Fuzhou Zhu
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072,China
- Frontiers Science Center for Synthetic Biology (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072,China
| | - Lin Zhang
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072,China
- Frontiers Science Center for Synthetic Biology (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072,China
- SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co., Ltd, Dalian 116045, China
| | - Jianping Wen
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072,China
- Frontiers Science Center for Synthetic Biology (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072,China
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3
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Lu C, Ramalho TP, Bisschops MMM, Wijffels RH, Martins Dos Santos VAP, Weusthuis RA. Crossing bacterial boundaries: The carbon catabolite repression system Crc-Hfq of Pseudomonas putida KT2440 as a tool to control translation in E. coli. N Biotechnol 2023; 77:20-29. [PMID: 37348756 DOI: 10.1016/j.nbt.2023.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/05/2023] [Accepted: 06/19/2023] [Indexed: 06/24/2023]
Abstract
As a global regulatory mechanism, carbon catabolite repression allows bacteria and eukaryal microbes to preferentially utilize certain substrates from a mixture of carbon sources. The mechanism varies among different species. In Pseudomonas spp., it is mainly mediated by the Crc-Hfq complex which binds to the 5' region of the target mRNAs, thereby inhibiting their translation. This molecular mechanism enables P. putida to rapidly adjust and fine-tune gene expression in changing environments. Hfq is an RNA-binding protein that is ubiquitous and highly conserved in bacterial species. Considering the characteristics of Hfq, and the widespread use and rapid response of Crc-Hfq in P. putida, this complex has the potential to become a general toolbox for post-transcriptional multiplex regulation. In this study, we demonstrate for the first time that transplanting the pseudomonal catabolite repression protein, Crc, into E. coli causes multiplex gene repression. Under the control of Crc, the production of a diester and its precursors was significantly reduced. The effects of Crc introduction on cell growth in both minimal and rich media were evaluated. Two potential factors - off-target effects and Hfq-sequestration - could explain negative effects on cell growth. Simultaneous reduction of off-targeting and increased sequestration of Hfq by the introduction of the small RNA CrcZ, indicated that Hfq sequestration plays a more prominent role in the negative side-effects. This suggests that the negative growth effect can be mitigated by well-controlled expression of Hfq. This study reveals the feasibility of controlling gene expression using heterologous regulation systems.
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Affiliation(s)
- Chunzhe Lu
- Bioprocess Engineering, Wageningen University and Research, 6700AA Wageningen, The Netherlands.
| | - Tiago P Ramalho
- Bioprocess Engineering, Wageningen University and Research, 6700AA Wageningen, The Netherlands
| | - Markus M M Bisschops
- Bioprocess Engineering, Wageningen University and Research, 6700AA Wageningen, The Netherlands
| | - Rene H Wijffels
- Bioprocess Engineering, Wageningen University and Research, 6700AA Wageningen, The Netherlands; Faculty of Biosciences and Aquaculture, Nord University, N-8049 Bodø, Norway
| | - Vitor A P Martins Dos Santos
- Bioprocess Engineering, Wageningen University and Research, 6700AA Wageningen, The Netherlands; Lifeglimmer GmbH, Berlin, Germany
| | - Ruud A Weusthuis
- Bioprocess Engineering, Wageningen University and Research, 6700AA Wageningen, The Netherlands
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Rauter M, Nietz D, Kunze G. Cutinase ACut2 from Blastobotrysraffinosifermentans for the Selective Desymmetrization of the Symmetric Diester Diethyl Adipate to the Monoester Monoethyl Adipate. Microorganisms 2022; 10:microorganisms10071316. [PMID: 35889035 PMCID: PMC9325033 DOI: 10.3390/microorganisms10071316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 12/04/2022] Open
Abstract
Monoethyl adipate (MEA) is a highly valuable monoester for activating resistance mechanisms and improving protective effects in pathogen-attacked plants. The cutinase ACut2 from the non-conventional yeast Blastobotrys (Arxula) raffinosifermentans (adeninivorans) was used for its synthesis by the desymmetrization of dicarboxylic acid diester diethyl adipate (DEA). Up to 78% MEA with 19% diacid adipic acid (AA) as by-product could be synthesized by the unpurified ACut2 culture supernatant from the B. raffinosifermentans overexpression strain. By adjusting pH and enzyme concentration, the selectivity of the free ACut2 culture supernatant was increased, yielding 95% MEA with 5% AA. Selectivity of the carrier immobilized ACut2 culture supernatant was also improved by pH adjustment during immobilization, as well as carrier enzyme loading, ultimately yielding 93% MEA with an even lower AA concentration of 3–4%. Thus, optimizations enabled the selective hydrolysis of DEA into MEA with only a minor AA impurity. In the up-scaling, a maximum of 98% chemical and 87.8% isolated MEA yield were obtained by the adsorbed enzyme preparation with a space time yield of 2.6 g L−1 h−1. The high monoester yields establish the ACut2-catalyzed biosynthesis as an alternative to existing methods.
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Affiliation(s)
- Marion Rauter
- Orgentis Chemicals GmbH, Bahnhofstr. 3–5, Gatersleben, D-06466 Stadt Seeland, Germany;
| | - Daniela Nietz
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, Gatersleben, D-06466 Stadt Seeland, Germany
| | - Gotthard Kunze
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, Gatersleben, D-06466 Stadt Seeland, Germany
- Correspondence:
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Williams SC, Austin RN. An Overview of the Electron-Transfer Proteins That Activate Alkane Monooxygenase (AlkB). Front Microbiol 2022; 13:845551. [PMID: 35295299 PMCID: PMC8918992 DOI: 10.3389/fmicb.2022.845551] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 01/24/2022] [Indexed: 11/13/2022] Open
Abstract
Alkane-oxidizing enzymes play an important role in the global carbon cycle. Alkane monooxygenase (AlkB) oxidizes most of the medium-chain length alkanes in the environment. The first AlkB identified was from P. putida GPo1 (initially known as P. oleovorans) in the early 1970s, and it continues to be the family member about which the most is known. This AlkB is found as part of the OCT operon, in which all of the key proteins required for growth on alkanes are present. The AlkB catalytic cycle requires that the diiron active site be reduced. In P. putida GPo1, electrons originate from NADH and arrive at AlkB via the intermediacy of a flavin reductase and an iron–sulfur protein (a rubredoxin). In this Mini Review, we will review what is known about the canonical arrangement of electron-transfer proteins that activate AlkB and, more importantly, point to several other arrangements that are possible. These other arrangements include the presence of a simpler rubredoxin than what is found in the canonical arrangement, as well as two other classes of AlkBs with fused electron-transfer partners. In one class, a rubredoxin is fused to the hydroxylase and in another less well-explored class, a ferredoxin reductase and a ferredoxin are fused to the hydroxylase. We review what is known about the biochemistry of these electron-transfer proteins, speculate on the biological significance of this diversity, and point to key questions for future research.
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Affiliation(s)
| | - Rachel Narehood Austin
- Department of Chemistry, Barnard College, Columbia University, New York City, NY, United States
- *Correspondence: Rachel Narehood Austin,
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Lee Y, Sathesh-Prabu C, Kwak GH, Bang I, Jung HW, Kim D, Lee SK. Enhanced production of nonanedioic acid from nonanoic acid by engineered Escherichia coli. Biotechnol J 2021; 17:e2000416. [PMID: 33964181 DOI: 10.1002/biot.202000416] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 05/06/2021] [Accepted: 05/06/2021] [Indexed: 11/06/2022]
Abstract
In this study, whole-cell biotransformation was conducted to produce nonanedioic acid from nonanoic acid by expressing the alkane hydroxylating system (AlkBGT) from Pseudomonas putida GPo1 in Escherichia coli. Following adaptive laboratory evolution, an efficient E. coli mutant strain, designated as MRE, was successfully obtained, demonstrating the fastest growth (27-fold higher) on nonanoic acid as the sole carbon source compared to the wild-type strain. Additionally, the MRE strain was engineered to block nonanoic acid degradation by deleting fadE. The resulting strain exhibited a 12.8-fold increase in nonanedioic acid production compared to the wild-type strain. Six mutations in acrR, Pcrp , dppA, PfadD , e14, and yeaR were identified in the mutant MRE strain, which was characterized using genomic modifications and RNA-sequencing. The acquired mutations were found to be beneficial for rapid growth and nonanedioic acid production.
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Affiliation(s)
- Yongjoo Lee
- School of Energy & Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Chandran Sathesh-Prabu
- School of Energy & Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Geun Hwa Kwak
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Ina Bang
- School of Energy & Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Hyun Wook Jung
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Donghyuk Kim
- School of Energy & Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea.,Department of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Sung Kuk Lee
- School of Energy & Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea.,Department of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
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7
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Williams SC, Forsberg AP, Lee J, Vizcarra CL, Lopatkin AJ, Austin RN. Investigation of the prevalence and catalytic activity of rubredoxin-fused alkane monooxygenases (AlkBs). J Inorg Biochem 2021; 219:111409. [PMID: 33752122 DOI: 10.1016/j.jinorgbio.2021.111409] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/28/2021] [Accepted: 02/21/2021] [Indexed: 10/21/2022]
Abstract
Interest in understanding the environmental distribution of the alkane monooxygenase (AlkB) enzyme led to the identification of over 100 distinct alkane monooxygenase (AlkB) enzymes containing a covalently bound, or fused, rubredoxin. The rubredoxin-fused AlkB from Dietzia cinnamea was cloned as a full-length protein and as a truncated protein with the rubredoxin domain deleted. A point mutation (V91W) was introduced into the full-length protein, with the goal of assessing how steric bulk in the putative substrate channel might affect selectivity. Based on activity studies with alkane and alkene substrates, the rubredoxin-fused AlkB oxidizes a similar range of alkane substrates relative to its rubredoxin domain-deletion counterpart. Oxidation of terminal alkenes generated both an epoxide and a terminal aldehyde. The products of V91W-mutant-catalyzed oxidation of alkenes had a higher aldehyde-to-epoxide ratio than the products formed in the presence of the wild type protein. These results are consistent with this mutation causing a structural change impacting substrate positioning.
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Affiliation(s)
- Shoshana C Williams
- Department of Chemistry, Barnard College, 3009 Broadway, New York, NY 10027, USA
| | - Allison P Forsberg
- Department of Chemistry, Barnard College, 3009 Broadway, New York, NY 10027, USA
| | - Juliet Lee
- Department of Chemistry, Barnard College, 3009 Broadway, New York, NY 10027, USA
| | - Christina L Vizcarra
- Department of Chemistry, Barnard College, 3009 Broadway, New York, NY 10027, USA
| | - Allison J Lopatkin
- Department of Biology, Barnard College, 3009 Broadway, New York, NY 10027, USA; Data Science Institute Columbia University, New York, NY 10027 USA
| | - Rachel N Austin
- Department of Chemistry, Barnard College, 3009 Broadway, New York, NY 10027, USA.
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Park HA, Choi KY. α, ω-Oxyfunctionalization of C12 alkanes via whole-cell biocatalysis of CYP153A from Marinobacter aquaeolei and a new CYP from Nocardia farcinica IFM10152. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107524] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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9
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Liu X, Wang W, Hu H, Lu X, Zhang L, Xu P, Tang H. 2-Hydroxy-4-(3′-oxo-3′H-benzofuran-2′-yliden)but-2-enoic acid biosynthesis from dibenzofuran using lateral dioxygenation in a Pseudomonas putida strain B6-2 (DSM 28064). BIORESOUR BIOPROCESS 2018. [DOI: 10.1186/s40643-018-0209-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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10
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van Nuland YM, Eggink G, Weusthuis RA. Combination of ester biosynthesis and ω-oxidation for production of mono-ethyl dicarboxylic acids and di-ethyl esters in a whole-cell biocatalytic setup with Escherichia coli. Microb Cell Fact 2017; 16:185. [PMID: 29096635 PMCID: PMC5667465 DOI: 10.1186/s12934-017-0803-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/30/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Medium chain length (C6-C12) α,ω-dicarboxylic acids (DCAs) and corresponding esters are important building blocks for the polymer industry. For DCAs of 12 carbon atoms and longer, a sustainable process based on monooxygenase catalyzed ω-oxidation of fatty-acids has been realized. For medium-chain DCAs with a shorter chain length however, such a process has not been developed yet, since monooxygenases poorly ω-oxidize medium-chain fatty acids (MCFAs). On the contrary, esterified MCFAs are ω-oxidized well by the AlkBGTHJ proteins from Pseudomonas putida GPo1. RESULTS We show that MCFAs can be efficiently esterified and subsequently ω-oxidized in vivo. We combined ethyl ester synthesis and ω-oxidation in one-pot, whole-cell biocatalysis in Escherichia coli. Ethyl ester production was achieved by applying acyl-CoA ligase AlkK and an alcohol acyltransferase, either AtfA or Eeb1. E. coli expressing these proteins in combination with the ω-oxidation pathway consisting of AlkBGTHJ, produced mono-ethyl DCAs directly from C6, C8 and C9 fatty acids. The highest molar yield was 0.75, for mono-ethyl azelate production from nonanoic acid. Furthermore, di-ethyl esters were produced. Diethyl suberate was produced most among the di-ethyl esters, with a molar yield of 0.24 from octanoic acid. CONCLUSION The results indicate that esterification of MCFAs and subsequent ω-oxidation to mono-ethyl DCAs via whole-cell biocatalysis is possible. This process could be the first step towards sustainable production of medium-chain DCAs and medium-chain di-ethyl esters.
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Affiliation(s)
- Youri M van Nuland
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands.
| | - Gerrit Eggink
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands.,Biobased Products, Wageningen University and Research, Wageningen, Netherlands
| | - Ruud A Weusthuis
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
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Biocatalytic, one-pot diterminal oxidation and esterification of n-alkanes for production of α,ω-diol and α,ω-dicarboxylic acid esters. Metab Eng 2017; 44:134-142. [DOI: 10.1016/j.ymben.2017.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/14/2017] [Accepted: 10/05/2017] [Indexed: 11/16/2022]
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12
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van Nuland YM, de Vogel FA, Eggink G, Weusthuis RA. Expansion of the ω-oxidation system AlkBGTL of Pseudomonas putida GPo1 with AlkJ and AlkH results in exclusive mono-esterified dicarboxylic acid production in E. coli. Microb Biotechnol 2017; 10:594-603. [PMID: 28321989 PMCID: PMC5404194 DOI: 10.1111/1751-7915.12607] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 01/11/2017] [Indexed: 12/17/2022] Open
Abstract
The AlkBGTL proteins coded on the alk operon from Pseudomonas putida GPo1 can selectively ω‐oxidize ethyl esters of C6 to C10 fatty acids in whole‐cell conversions with Escherichia coli. The major product in these conversions is the ω‐alcohol. However, AlkB also has the capacity to overoxidize the substrate to the ω‐aldehyde and ω‐acid. In this study, we show that alcohol dehydrogenase AlkJ and aldehyde dehydrogenase AlkH are able to oxidize ω‐alcohols and ω‐aldehydes of esterified fatty acids respectively. Resting E. coli expressing AlkBGTHJL enabled exclusive mono‐ethyl azelate production from ethyl nonanoate, with an initial specific activity of 61 U gcdw−1. Within 2 h, this strain produced 3.53 mM mono‐ethyl azelate, with a yield of 0.68 mol mol−1. This strain also produced mono‐ethyl dicarboxylic acids from ethyl esters of C6 to C10 fatty acids and mono‐methyl azelate from methyl nonanoate. Adding ethyl nonanoate dissolved in carrier solvent bis‐(2‐ethylhexyl) phthalate enabled an increase in product titres to 15.55 mM in two‐liquid phase conversions. These findings indicate that E. coli expressing AlkBGTHJL is an effective producer of mono‐esterified dicarboxylic acids from fatty acid esters.
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Affiliation(s)
- Youri M van Nuland
- Bioprocess Engineering, Wageningen University and Research, Wageningen, the Netherlands
| | - Fons A de Vogel
- Bioprocess Engineering, Wageningen University and Research, Wageningen, the Netherlands
| | - Gerrit Eggink
- Bioprocess Engineering, Wageningen University and Research, Wageningen, the Netherlands.,Biobased Products, Wageningen University and Research, Wageningen, the Netherlands
| | - Ruud A Weusthuis
- Bioprocess Engineering, Wageningen University and Research, Wageningen, the Netherlands
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