1
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Arnodo D, De Nardi F, Parisotto S, De Nardo E, Cananà S, Salvatico F, De Marchi E, Scarpi D, Blangetti M, Occhiato EG, Prandi C. Asymmetric Reduction of Cyclic Imines by Imine Reductase Enzymes in Non-Conventional Solvents. CHEMSUSCHEM 2024; 17:e202301243. [PMID: 37751248 DOI: 10.1002/cssc.202301243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/22/2023] [Accepted: 09/26/2023] [Indexed: 09/27/2023]
Abstract
The first enantioselective reduction of 2-substituted cyclic imines to the corresponding amines (pyrrolidines, piperidines, and azepines) by imine reductases (IREDs) in non-conventional solvents is reported. The best results were obtained in a glycerol/phosphate buffer 1 : 1 mixture, in which heterocyclic amines were produced with full conversions (>99 %), moderate to good yields (22-84 %) and excellent S-enantioselectivities (up to >99 % ee). Remarkably, the process can be performed at a 100 mM substrate loading, which, for the model compound, means a concentration of 14.5 g L-1 . A fed-batch protocol was also developed for a convenient scale-up transformation, and one millimole of substrate 1 a was readily converted into 120 mg of enantiopure amine (S)-2 a with a remarkable 80 % overall yield. This aspect strongly contributes to making the process potentially attractive for large-scale applications in terms of economic and environmental sustainability for a good number of substrates used to produce enantiopure cyclic amines of high pharmaceutical interest.
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Affiliation(s)
- Davide Arnodo
- Dipartimento di Chimica, Università degli Studi di Torino, Via Pietro Giuria 7, 10125, Torino, Italy
| | - Federica De Nardi
- Dipartimento di Chimica, Università degli Studi di Torino, Via Pietro Giuria 7, 10125, Torino, Italy
| | - Stefano Parisotto
- Dipartimento di Chimica, Università degli Studi di Torino, Via Pietro Giuria 7, 10125, Torino, Italy
| | - Eugenio De Nardo
- Dipartimento di Chimica, Università degli Studi di Torino, Via Pietro Giuria 7, 10125, Torino, Italy
| | - Stefania Cananà
- Dipartimento di Chimica, Università degli Studi di Torino, Via Pietro Giuria 7, 10125, Torino, Italy
- Scuola Universitaria Superiore I.U.S.S. Pavia, Piazza Vittoria 15, 2700, Pavia, Italy
| | - Federica Salvatico
- Dipartimento di Chimica, Università degli Studi di Torino, Via Pietro Giuria 7, 10125, Torino, Italy
| | - Elisa De Marchi
- Dipartimento di Chimica 'Ugo Schiff', Università degli Studi di Firenze, Via della Lastruccia 13, 50019, Sesto Fiorentino, Italy
| | - Dina Scarpi
- Dipartimento di Chimica 'Ugo Schiff', Università degli Studi di Firenze, Via della Lastruccia 13, 50019, Sesto Fiorentino, Italy
| | - Marco Blangetti
- Dipartimento di Chimica, Università degli Studi di Torino, Via Pietro Giuria 7, 10125, Torino, Italy
| | - Ernesto G Occhiato
- Dipartimento di Chimica 'Ugo Schiff', Università degli Studi di Firenze, Via della Lastruccia 13, 50019, Sesto Fiorentino, Italy
| | - Cristina Prandi
- Dipartimento di Chimica, Università degli Studi di Torino, Via Pietro Giuria 7, 10125, Torino, Italy
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2
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Alberto Alcalá-Orozco E, Grote V, Fiebig T, Klamt S, Reichl U, Rexer T. A Cell-Free Multi-enzyme Cascade Reaction for the Synthesis of CDP-Glycerol. Chembiochem 2023; 24:e202300463. [PMID: 37578628 DOI: 10.1002/cbic.202300463] [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: 06/21/2023] [Revised: 08/14/2023] [Accepted: 08/14/2023] [Indexed: 08/15/2023]
Abstract
CDP-glycerol is a nucleotide-diphosphate-activated version of glycerol. In nature, it is required for the biosynthesis of teichoic acid in Gram-positive bacteria, which is an appealing target epitope for the development of new vaccines. Here, a cell-free multi-enzyme cascade was developed to synthetize nucleotide-activated glycerol from the inexpensive and readily available substrates cytidine and glycerol. The cascade comprises five recombinant enzymes expressed in Escherichia coli that were purified by immobilized metal affinity chromatography. As part of the cascade, ATP is regenerated in situ from polyphosphate to reduce synthesis costs. The enzymatic cascade was characterized at the laboratory scale, and the products were analyzed by high-performance anion-exchange chromatography (HPAEC)-UV and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). After the successful synthesis had been confirmed, a design-of-experiments approach was used to screen for optimal operation conditions (temperature, pH value and MgCl2 concentration). Overall, a substrate conversion of 89 % was achieved with respect to the substrate cytidine.
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Affiliation(s)
- E Alberto Alcalá-Orozco
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, 39106, Magdeburg, Germany
| | - Valerian Grote
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, 39106, Magdeburg, Germany
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, 30625, Hannover, Germany
| | - Steffen Klamt
- Analysis and Redesign of Biological Networks, Max Planck Institute for Dynamics of Complex Technical Systems, 39106, Magdeburg, Germany
| | - Udo Reichl
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, 39106, Magdeburg, Germany
- Chair of Bioprocess Engineering, Otto-von-Guericke University Magdeburg, 39104, Magdeburg, Germany
| | - Thomas Rexer
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, 39106, Magdeburg, Germany
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3
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Semi-Rational Design of Diaminopimelate Dehydrogenase from Symbiobacterium thermophilum Improved Its Activity toward Hydroxypyruvate for D-serine Synthesis. Catalysts 2023. [DOI: 10.3390/catal13030576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023] Open
Abstract
D-serine plays an essential role in the field of medicine and cosmetics. Diaminopimelate dehydrogenase (DAPDH) is a kind of oxidoreductase that can reduce keto acid into the corresponding D-amino acid. Because of its high stereoselectivity and lack of by-product production, DAPDH has become the preferred enzyme for the efficient one-step synthesis of D-amino acids. However, the types of DAPDH with a reductive amination function reported so far are limited. Although the DAPDH from Symbiobacterium thermophilum (StDAPDH) demonstrates reductive amination activity toward a series of macromolecular keto acids, activity toward hydroxypyruvate (HPPA) for D-serine synthesis has not been reported. In this study, we investigated the activity of the available StDAPDH/H227V toward HPPA by measuring the desired product D-serine. After homologous structure modeling and docking analysis concerning the substrate-binding pocket, four residues, D92, D122, M152, and N253, in the active pocket were predicted for catalyzing HPPA. Through single-point saturation mutation and iterative mutation, a mutant D92E/D122W/M152S was obtained with an 8.64-fold increase in enzyme activity, exhibiting a specific activity of 0.19 U/mg and kcat value of 3.96 s−1 toward HPPA. Using molecular dynamics simulation, it was speculated that the increase in enzyme activity might be related to the change in substrate pocket size and the enhancement of the interactions between the substrate and key residues.
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4
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Zhan Z, Xu Z, Yu S, Feng J, Liu F, Yao P, Wu Q, Zhu D. Stereocomplementary Synthesis of a Key Intermediate for Tofacitinib via Enzymatic Dynamic Kinetic Resolution‐Reductive Amination. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202200361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Zhuangzhuang Zhan
- Key Laboratory of Industrial Fermentation Microbiology Ministry of Education College of Biotechnology Tianjin University of Science & Technology Tianjin 300457 People's Republic of China
- National Technology Innovation Center of Synthetic Biology National Engineering Research Center of Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 People's Republic of China
| | - Zefei Xu
- National Technology Innovation Center of Synthetic Biology National Engineering Research Center of Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 People's Republic of China
| | - Shanshan Yu
- National Technology Innovation Center of Synthetic Biology National Engineering Research Center of Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 People's Republic of China
| | - Jinhui Feng
- National Technology Innovation Center of Synthetic Biology National Engineering Research Center of Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 People's Republic of China
| | - Fufeng Liu
- Key Laboratory of Industrial Fermentation Microbiology Ministry of Education College of Biotechnology Tianjin University of Science & Technology Tianjin 300457 People's Republic of China
| | - Peiyuan Yao
- National Technology Innovation Center of Synthetic Biology National Engineering Research Center of Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 People's Republic of China
| | - Qiaqing Wu
- National Technology Innovation Center of Synthetic Biology National Engineering Research Center of Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 People's Republic of China
| | - Dunming Zhu
- National Technology Innovation Center of Synthetic Biology National Engineering Research Center of Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 People's Republic of China
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5
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Aleku GA, Titchiner GR, Roberts GW, Derrington SR, Marshall JR, Hollfelder F, Turner NJ, Leys D. Enzymatic N-Allylation of Primary and Secondary Amines Using Renewable Cinnamic Acids Enabled by Bacterial Reductive Aminases. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2022; 10:6794-6806. [PMID: 35634269 PMCID: PMC9131517 DOI: 10.1021/acssuschemeng.2c01180] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 04/25/2022] [Indexed: 06/15/2023]
Abstract
Allylic amines are a versatile class of synthetic precursors of many valuable nitrogen-containing organic compounds, including pharmaceuticals. Enzymatic allylic amination methods provide a sustainable route to these compounds but are often restricted to allylic primary amines. We report a biocatalytic system for the reductive N-allylation of primary and secondary amines, using biomass-derivable cinnamic acids. The two-step one-pot system comprises an initial carboxylate reduction step catalyzed by a carboxylic acid reductase to generate the corresponding α,β-unsaturated aldehyde in situ. This is followed by reductive amination of the aldehyde catalyzed by a bacterial reductive aminase pIR23 or BacRedAm to yield the corresponding allylic amine. We exploited pIR23, a prototype bacterial reductive aminase, self-sufficient in catalyzing formal reductive amination of α,β-unsaturated aldehydes with various amines, generating a broad range of secondary and tertiary amines accessed in up to 94% conversion under mild reaction conditions. Analysis of products isolated from preparative reactions demonstrated that only selective hydrogenation of the C=N bond had occurred, preserving the adjacent alkene moiety. This process represents an environmentally benign and sustainable approach for the synthesis of secondary and tertiary allylic amine frameworks, using renewable allylating reagents and avoiding harsh reaction conditions. The selectivity of the system ensures that bis-allylation of the alkylamines and (over)reduction of the alkene moiety are avoided.
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Affiliation(s)
- Godwin A. Aleku
- Manchester
Institute of Biotechnology, Department of Chemistry, University of Manchester, Manchester, 131 Princess Street, Manchester M1 7DN, U.K.
- Department
of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, U.K.
| | - Gabriel R. Titchiner
- Manchester
Institute of Biotechnology, Department of Chemistry, University of Manchester, Manchester, 131 Princess Street, Manchester M1 7DN, U.K.
| | - George W. Roberts
- Manchester
Institute of Biotechnology, Department of Chemistry, University of Manchester, Manchester, 131 Princess Street, Manchester M1 7DN, U.K.
| | - Sasha R. Derrington
- Manchester
Institute of Biotechnology, Department of Chemistry, University of Manchester, Manchester, 131 Princess Street, Manchester M1 7DN, U.K.
| | - James R. Marshall
- Manchester
Institute of Biotechnology, Department of Chemistry, University of Manchester, Manchester, 131 Princess Street, Manchester M1 7DN, U.K.
| | - Florian Hollfelder
- Department
of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, U.K.
| | - Nicholas J. Turner
- Manchester
Institute of Biotechnology, Department of Chemistry, University of Manchester, Manchester, 131 Princess Street, Manchester M1 7DN, U.K.
| | - David Leys
- Manchester
Institute of Biotechnology, Department of Chemistry, University of Manchester, Manchester, 131 Princess Street, Manchester M1 7DN, U.K.
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6
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Woodley JM. Ensuring the Sustainability of Biocatalysis. CHEMSUSCHEM 2022; 15:e202102683. [PMID: 35084801 DOI: 10.1002/cssc.202102683] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/20/2022] [Indexed: 06/14/2023]
Abstract
Biocatalysis offers many attractive features for the synthetic chemist. In many cases, the high selectivity and ability to tailor specific enzyme features via protein engineering already make it the catalyst of choice. From the perspective of sustainability, several features such as catalysis under mild conditions and use of a renewable and biodegradable catalyst also look attractive. Nevertheless, to be sustainable at a larger scale it will be essential to develop processes operating at far higher concentrations of product, and which make better use of the enzyme via improved stability. In this Concept, it is argued that a particular emphasis on these specific metrics is of particular importance for the future implementation of biocatalysis in industry, at a level that fulfills its true potential.
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Affiliation(s)
- John M Woodley
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800, Kgs Lyngby, Denmark
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7
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Li Y, Hu N, Xu Z, Cui Y, Feng J, Yao P, Wu Q, Zhu D, Ma Y. Asymmetric Synthesis of N-Substituted 1,2-Amino Alcohols from Simple Aldehydes and Amines by One-Pot Sequential Enzymatic Hydroxymethylation and Asymmetric Reductive Amination. Angew Chem Int Ed Engl 2022; 61:e202116344. [PMID: 35166000 DOI: 10.1002/anie.202116344] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Indexed: 01/10/2023]
Abstract
The chiral N-substituted 1,2-amino alcohol motif is found in many natural and synthetic bioactive compounds. In this study, enzymatic asymmetric reductive amination of α-hydroxymethyl ketones with enantiocomplementary imine reductases (IREDs) enabled the synthesis of chiral N-substituted 1,2-amino alcohols with excellent ee values (91-99 %) in moderate to high yields (41-84 %). Furthermore, a one-pot, two-step enzymatic process involving benzaldehyde lyase-catalyzed hydroxymethylation of aldehydes and subsequent asymmetric reductive amination was developed, offering an environmentally friendly and economical way to produce N-substituted 1,2-amino alcohols from readily available simple aldehydes and amines. This methodology was then applied to rapidly access a key synthetic intermediate of anti-malaria and cytotoxic tetrahydroquinoline alkaloids.
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Affiliation(s)
- Yu Li
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China.,University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China
| | - Na Hu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China.,University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China
| | - Zefei Xu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China
| | - Yunfeng Cui
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China
| | - Jinhui Feng
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China.,University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China
| | - Peiyuan Yao
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China.,University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China
| | - Qiaqing Wu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China.,University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China
| | - Dunming Zhu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China.,University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing, 100049, China
| | - Yanhe Ma
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center for Synthetic Biology, Tianjin, 300308, China
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8
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Multifunctional biocatalyst for conjugate reduction and reductive amination. Nature 2022; 604:86-91. [PMID: 35388195 DOI: 10.1038/s41586-022-04458-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Accepted: 01/20/2022] [Indexed: 11/08/2022]
Abstract
Chiral amine diastereomers are ubiquitous in pharmaceuticals and agrochemicals1, yet their preparation often relies on low-efficiency multi-step synthesis2. These valuable compounds must be manufactured asymmetrically, as their biochemical properties can differ based on the chirality of the molecule. Herein we characterize a multifunctional biocatalyst for amine synthesis, which operates using a mechanism that is, to our knowledge, previously unreported. This enzyme (EneIRED), identified within a metagenomic imine reductase (IRED) collection3 and originating from an unclassified Pseudomonas species, possesses an unusual active site architecture that facilitates amine-activated conjugate alkene reduction followed by reductive amination. This enzyme can couple a broad selection of α,β-unsaturated carbonyls with amines for the efficient preparation of chiral amine diastereomers bearing up to three stereocentres. Mechanistic and structural studies have been carried out to delineate the order of individual steps catalysed by EneIRED, which have led to a proposal for the overall catalytic cycle. This work shows that the IRED family can serve as a platform for facilitating the discovery of further enzymatic activities for application in synthetic biology and organic synthesis.
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9
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Li Y, Hu N, Xu Z, Cui Y, Feng J, Yao P, Wu Q, Zhu D, Ma Y. Asymmetric Synthesis of
N
‐Substituted 1,2‐Amino Alcohols from Simple Aldehydes and Amines by One‐Pot Sequential Enzymatic Hydroxymethylation and Asymmetric Reductive Amination. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202116344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yu Li
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
- University of Chinese Academy of Sciences 19A Yuquan Road Beijing 100049 China
| | - Na Hu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
- University of Chinese Academy of Sciences 19A Yuquan Road Beijing 100049 China
| | - Zefei Xu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
| | - Yunfeng Cui
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
| | - Jinhui Feng
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
- University of Chinese Academy of Sciences 19A Yuquan Road Beijing 100049 China
| | - Peiyuan Yao
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
- University of Chinese Academy of Sciences 19A Yuquan Road Beijing 100049 China
| | - Qiaqing Wu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
- University of Chinese Academy of Sciences 19A Yuquan Road Beijing 100049 China
| | - Dunming Zhu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
- University of Chinese Academy of Sciences 19A Yuquan Road Beijing 100049 China
| | - Yanhe Ma
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences National Technology Innovation Center for Synthetic Biology Tianjin 300308 China
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10
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Phelan RM, Abrahamson MJ, Brown JTC, Zhang RK, Zwick CR. Development of Scalable Processes with Underutilized Biocatalyst Classes. Org Process Res Dev 2022. [DOI: 10.1021/acs.oprd.1c00467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ryan M. Phelan
- Process Research and Development, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Michael J. Abrahamson
- Operations Science and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Jesse T. C. Brown
- Process Research and Development, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Ruijie K. Zhang
- Discovery Chemistry and Technology, AbbVie Inc., North Chicago, Illinois 60064, United States
| | - Christian R. Zwick
- Process Research and Development, AbbVie Inc., North Chicago, Illinois 60064, United States
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11
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Meissner MP, Woodley JM. Mass-based biocatalyst metrics to guide protein engineering and bioprocess development. Nat Catal 2022. [DOI: 10.1038/s41929-021-00728-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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12
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Gilio AK, Thorpe TW, Turner N, Grogan G. Reductive aminations by imine reductases: from milligrams to tons. Chem Sci 2022; 13:4697-4713. [PMID: 35655886 PMCID: PMC9067572 DOI: 10.1039/d2sc00124a] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 04/06/2022] [Indexed: 12/22/2022] Open
Abstract
The synthesis of secondary and tertiary amines through the reductive amination of carbonyl compounds is one of the most significant reactions in synthetic chemistry. Asymmetric reductive amination for the formation of chiral amines, which are required for the synthesis of pharmaceuticals and other bioactive molecules, is often achieved through transition metal catalysis, but biocatalytic methods of chiral amine production have also been a focus of interest owing to their selectivity and sustainability. The discovery of asymmetric reductive amination by imine reductase (IRED) and reductive aminase (RedAm) enzymes has served as the starting point for a new industrial approach to the production of chiral amines, leading from laboratory-scale milligram transformations to ton-scale reactions that are now described in the public domain. In this perspective we trace the development of the IRED-catalyzed reductive amination reaction from its discovery to its industrial application on kg to ton scale. In addition to surveying examples of the synthetic chemistry that has been achieved with the enzymes, the contribution of structure and protein engineering to the understanding of IRED-catalyzed reductive amination is described, and the consequent benefits for activity, selectivity and stability in the design of process suitable catalysts. IRED-catalyzed reductive aminations have progressed from mg to ton scale, through advances in enzyme discovery, protein engineering and process biocatalysis.![]()
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Affiliation(s)
- Amelia K. Gilio
- Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
| | - Thomas W. Thorpe
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester, M1 7DN, UK
| | - Nicholas Turner
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester, M1 7DN, UK
| | - Gideon Grogan
- Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
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13
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Simić S, Zukić E, Schmermund L, Faber K, Winkler CK, Kroutil W. Shortening Synthetic Routes to Small Molecule Active Pharmaceutical Ingredients Employing Biocatalytic Methods. Chem Rev 2021; 122:1052-1126. [PMID: 34846124 DOI: 10.1021/acs.chemrev.1c00574] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Biocatalysis, using enzymes for organic synthesis, has emerged as powerful tool for the synthesis of active pharmaceutical ingredients (APIs). The first industrial biocatalytic processes launched in the first half of the last century exploited whole-cell microorganisms where the specific enzyme at work was not known. In the meantime, novel molecular biology methods, such as efficient gene sequencing and synthesis, triggered breakthroughs in directed evolution for the rapid development of process-stable enzymes with broad substrate scope and good selectivities tailored for specific substrates. To date, enzymes are employed to enable shorter, more efficient, and more sustainable alternative routes toward (established) small molecule APIs, and are additionally used to perform standard reactions in API synthesis more efficiently. Herein, large-scale synthetic routes containing biocatalytic key steps toward >130 APIs of approved drugs and drug candidates are compared with the corresponding chemical protocols (if available) regarding the steps, reaction conditions, and scale. The review is structured according to the functional group formed in the reaction.
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Affiliation(s)
- Stefan Simić
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz, Austria
| | - Erna Zukić
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz, Austria
| | - Luca Schmermund
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz, Austria
| | - Kurt Faber
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz, Austria
| | - Christoph K Winkler
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz, Austria
| | - Wolfgang Kroutil
- Institute of Chemistry, University of Graz, NAWI Graz, Heinrichstraße 28, 8010 Graz, Austria.,Field of Excellence BioHealth─University of Graz, 8010 Graz, Austria.,BioTechMed Graz, 8010 Graz, Austria
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14
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Sellés Vidal L, Murray JW, Heap JT. Versatile selective evolutionary pressure using synthetic defect in universal metabolism. Nat Commun 2021; 12:6859. [PMID: 34824282 PMCID: PMC8616928 DOI: 10.1038/s41467-021-27266-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 11/04/2021] [Indexed: 11/13/2022] Open
Abstract
The non-natural needs of industrial applications often require new or improved enzymes. The structures and properties of enzymes are difficult to predict or design de novo. Instead, semi-rational approaches mimicking evolution entail diversification of parent enzymes followed by evaluation of isolated variants. Artificial selection pressures coupling desired enzyme properties to cell growth could overcome this key bottleneck, but are usually narrow in scope. Here we show diverse enzymes using the ubiquitous cofactors nicotinamide adenine dinucleotide (NAD) or nicotinamide adenine dinucleotide phosphate (NADP) can substitute for defective NAD regeneration, representing a very broadly-applicable artificial selection. Inactivation of Escherichia coli genes required for anaerobic NAD regeneration causes a conditional growth defect. Cells are rescued by foreign enzymes connected to the metabolic network only via NAD or NADP, but only when their substrates are supplied. Using this principle, alcohol dehydrogenase, imine reductase and nitroreductase variants with desired selectivity modifications, and a high-performing isopropanol metabolic pathway, are isolated from libraries of millions of variants in single-round experiments with typical limited information to guide design.
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Affiliation(s)
- Lara Sellés Vidal
- grid.7445.20000 0001 2113 8111Imperial College Centre for Synthetic Biology, Imperial College London, London, SW7 2AZ UK ,grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
| | - James W. Murray
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
| | - John T. Heap
- grid.7445.20000 0001 2113 8111Imperial College Centre for Synthetic Biology, Imperial College London, London, SW7 2AZ UK ,grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK ,grid.4563.40000 0004 1936 8868School of Life Sciences, The University of Nottingham, Biodiscovery Institute, University Park, Nottingham, NG7 2RD UK
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15
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Sangster JJ, Marshall JR, Turner NJ, Mangas-Sanchez J. New Trends and Future Opportunities in the Enzymatic Formation of C-C, C-N, and C-O bonds. Chembiochem 2021; 23:e202100464. [PMID: 34726813 PMCID: PMC9401909 DOI: 10.1002/cbic.202100464] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/29/2021] [Indexed: 01/04/2023]
Abstract
Organic chemistry provides society with fundamental products we use daily. Concerns about the impact that the chemical industry has over the environment is propelling major changes in the way we manufacture chemicals. Biocatalysis offers an alternative to other synthetic approaches as it employs enzymes, Nature's catalysts, to carry out chemical transformations. Enzymes are biodegradable, come from renewable sources, operate under mild reaction conditions, and display high selectivities in the processes they catalyse. As a highly multidisciplinary field, biocatalysis benefits from advances in different areas, and developments in the fields of molecular biology, bioinformatics, and chemical engineering have accelerated the extension of the range of available transformations (E. L. Bell et al., Nat. Rev. Meth. Prim. 2021, 1, 1-21). Recently, we surveyed advances in the expansion of the scope of biocatalysis via enzyme discovery and protein engineering (J. R. Marshall et al., Tetrahedron 2021, 82, 131926). Herein, we focus on novel enzymes currently available to the broad synthetic community for the construction of new C-C, C-N and C-O bonds, with the purpose of providing the non-specialist with new and alternative tools for chiral and sustainable chemical synthesis.
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Affiliation(s)
- Jack J Sangster
- Department of Chemistry, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - James R Marshall
- Department of Chemistry, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Nicholas J Turner
- Department of Chemistry, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Juan Mangas-Sanchez
- Institute of Chemical Synthesis and Homogeneous Catalysis, Spanish National Research Council (CSIC), Pedro Cerbuna 12, 50009, Zaragoza, Spain.,ARAID Foundation, Zaragoza, Spain
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16
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Yao P, Marshall JR, Xu Z, Lim J, Charnock SJ, Zhu D, Turner NJ. Asymmetric Synthesis of N-Substituted α-Amino Esters from α-Ketoesters via Imine Reductase-Catalyzed Reductive Amination. Angew Chem Int Ed Engl 2021; 60:8717-8721. [PMID: 33555620 PMCID: PMC8048798 DOI: 10.1002/anie.202016589] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/01/2021] [Indexed: 11/12/2022]
Abstract
N-Substituted α-amino esters are widely used as chiral intermediates in a range of pharmaceuticals. Here we report the enantioselective biocatalyic synthesis of N-substituted α-amino esters through the direct reductive coupling of α-ketoesters and amines employing sequence diverse metagenomic imine reductases (IREDs). Both enantiomers of N-substituted α-amino esters were obtained with high conversion and excellent enantioselectivity under mild reaction conditions. In addition >20 different preparative scale transformations were performed highlighting the scalability of this system.
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Affiliation(s)
- Peiyuan Yao
- Department of ChemistryUniversity of ManchesterManchester Institute of Biotechnology131 Princess StreetManchesterM1 7DNUK
- National Technology Innovation Center of Synthetic BiologyNational Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic TechnologyTianjin Institute of Industrial BiotechnologyChinese Academy of Sciences32 Xi Qi Dao, Tianjin Airport Economic AreaTianjin300308P.R. China
| | - James R. Marshall
- Department of ChemistryUniversity of ManchesterManchester Institute of Biotechnology131 Princess StreetManchesterM1 7DNUK
| | - Zefei Xu
- National Technology Innovation Center of Synthetic BiologyNational Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic TechnologyTianjin Institute of Industrial BiotechnologyChinese Academy of Sciences32 Xi Qi Dao, Tianjin Airport Economic AreaTianjin300308P.R. China
| | - Jesmine Lim
- Prozomix LtdBuilding 4, West End Ind. EstateHaltwhistleNE49 9HAUK
| | | | - Dunming Zhu
- National Technology Innovation Center of Synthetic BiologyNational Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic TechnologyTianjin Institute of Industrial BiotechnologyChinese Academy of Sciences32 Xi Qi Dao, Tianjin Airport Economic AreaTianjin300308P.R. China
| | - Nicholas J. Turner
- Department of ChemistryUniversity of ManchesterManchester Institute of Biotechnology131 Princess StreetManchesterM1 7DNUK
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17
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Yao P, Marshall JR, Xu Z, Lim J, Charnock SJ, Zhu D, Turner NJ. Asymmetric Synthesis of
N
‐Substituted α‐Amino Esters from α‐Ketoesters via Imine Reductase‐Catalyzed Reductive Amination. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016589] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Peiyuan Yao
- Department of Chemistry University of Manchester Manchester Institute of Biotechnology 131 Princess Street Manchester M1 7DN UK
- National Technology Innovation Center of Synthetic Biology National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 P.R. China
| | - James R. Marshall
- Department of Chemistry University of Manchester Manchester Institute of Biotechnology 131 Princess Street Manchester M1 7DN UK
| | - Zefei Xu
- National Technology Innovation Center of Synthetic Biology National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 P.R. China
| | - Jesmine Lim
- Prozomix Ltd Building 4, West End Ind. Estate Haltwhistle NE49 9HA UK
| | - Simon J. Charnock
- Prozomix Ltd Building 4, West End Ind. Estate Haltwhistle NE49 9HA UK
| | - Dunming Zhu
- National Technology Innovation Center of Synthetic Biology National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology Tianjin Institute of Industrial Biotechnology Chinese Academy of Sciences 32 Xi Qi Dao, Tianjin Airport Economic Area Tianjin 300308 P.R. China
| | - Nicholas J. Turner
- Department of Chemistry University of Manchester Manchester Institute of Biotechnology 131 Princess Street Manchester M1 7DN UK
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18
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Marshall JR, Yao P, Montgomery SL, Finnigan JD, Thorpe TW, Palmer RB, Mangas-Sanchez J, Duncan RAM, Heath RS, Graham KM, Cook DJ, Charnock SJ, Turner NJ. Screening and characterization of a diverse panel of metagenomic imine reductases for biocatalytic reductive amination. Nat Chem 2021; 13:140-148. [PMID: 33380742 PMCID: PMC7116802 DOI: 10.1038/s41557-020-00606-w] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 11/10/2020] [Indexed: 01/30/2023]
Abstract
Finding faster and simpler ways to screen protein sequence space to enable the identification of new biocatalysts for asymmetric synthesis remains both a challenge and a rate-limiting step in enzyme discovery. Biocatalytic strategies for the synthesis of chiral amines are increasingly attractive and include enzymatic asymmetric reductive amination, which offers an efficient route to many of these high-value compounds. Here we report the discovery of over 300 new imine reductases and the production of a large (384 enzymes) and sequence-diverse panel of imine reductases available for screening. We also report the development of a facile high-throughput screen to interrogate their activity. Through this approach we identified imine reductase biocatalysts capable of accepting structurally demanding ketones and amines, which include the preparative synthesis of N-substituted β-amino ester derivatives via a dynamic kinetic resolution process, with excellent yields and stereochemical purities.
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Affiliation(s)
- James R. Marshall
- Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, Manchester, UK
| | - Peiyuan Yao
- Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, Manchester, UK
- National Engineering Laboratory for Industrial Enzymes, Tianjin Engineering Research Centre of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin Airport Economic Park, Tianjin, People’s Republic of China
| | - Sarah L. Montgomery
- Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, Manchester, UK
| | | | - Thomas W. Thorpe
- Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, Manchester, UK
| | - Ryan B. Palmer
- Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, Manchester, UK
| | - Juan Mangas-Sanchez
- Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, Manchester, UK
| | | | - Rachel S. Heath
- Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, Manchester, UK
| | | | - Darren J. Cook
- Prozomix, Building 4, West End Ind. Estate, Haltwhistle, UK
| | | | - Nicholas J. Turner
- Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, Manchester, UK
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19
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Slagman S, Fessner WD. Biocatalytic routes to anti-viral agents and their synthetic intermediates. Chem Soc Rev 2021; 50:1968-2009. [DOI: 10.1039/d0cs00763c] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
An assessment of biocatalytic strategies for the synthesis of anti-viral agents, offering guidelines for the development of sustainable production methods for a future COVID-19 remedy.
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Affiliation(s)
- Sjoerd Slagman
- Institut für Organische Chemie und Biochemie
- Technische Universität Darmstadt
- Germany
| | - Wolf-Dieter Fessner
- Institut für Organische Chemie und Biochemie
- Technische Universität Darmstadt
- Germany
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20
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Ducrot L, Bennett M, Grogan G, Vergne‐Vaxelaire C. NAD(P)H‐Dependent Enzymes for Reductive Amination: Active Site Description and Carbonyl‐Containing Compound Spectrum. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000870] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Laurine Ducrot
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry Université Paris-Saclay 91057 Evry France
| | - Megan Bennett
- York Structural Biology Laboratory Department of Chemistry University of York, Heslington York YO10 5DD UK
| | - Gideon Grogan
- York Structural Biology Laboratory Department of Chemistry University of York, Heslington York YO10 5DD UK
| | - Carine Vergne‐Vaxelaire
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry Université Paris-Saclay 91057 Evry France
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21
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Xu Z, Yao P, Sheng X, Li J, Li J, Yu S, Feng J, Wu Q, Zhu D. Biocatalytic Access to 1,4-Diazepanes via Imine Reductase-Catalyzed Intramolecular Asymmetric Reductive Amination. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02400] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Zefei Xu
- University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing 100049, China
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xi Qi Dao, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Peiyuan Yao
- University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing 100049, China
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xi Qi Dao, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Xiang Sheng
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm SE-10691, Sweden
| | - Jinlong Li
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xi Qi Dao, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Jianjiong Li
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xi Qi Dao, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Shanshan Yu
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xi Qi Dao, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Jinhui Feng
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xi Qi Dao, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Qiaqing Wu
- University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing 100049, China
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xi Qi Dao, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Dunming Zhu
- University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing 100049, China
- National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 Xi Qi Dao, Tianjin Airport Economic Area, Tianjin 300308, China
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22
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Affiliation(s)
- Bernhard Hauer
- Institute of Biochemistry and Technical Biochemistry, Department of Technical Biochemistry, Universitaet Stuttgart, Allmandring 31, 70569 Stuttgart, Germany
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23
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Meyer LE, Brundiek H, von Langermann J. Integration of ion exchange resin materials for a downstream-processing approach of an imine reductase-catalyzed reaction. Biotechnol Prog 2020; 36:e3024. [PMID: 32410373 DOI: 10.1002/btpr.3024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 04/21/2020] [Accepted: 05/09/2020] [Indexed: 12/31/2022]
Abstract
In this study, an ion exchange resin-based downstream-processing concept for imine reductase (IRED)-catalyzed reactions was investigated. As a model reaction, 2-methylpyrroline was converted to its corresponding product (S)-2-methylpyrrolidine with >99% of conversion by the (S)-selective IRED from Paenibacillus elgii B69. Under optimized reaction conditions full conversion was achieved using a substrate concentration of 150 and 500 mmol/L of d-glucose. Seven commercially available cation- and anion-exchange resins were studied with respect to their ability to recover the product from the reaction solution. Without any pretreatment, cation-exchange resins Amberlite IR-120(H), IRN-150, Dowex Monosphere 650C, and Dowex Marathon MSC showed high recovery capacities (up to >90%). A 150-ml preparative scale reaction was performed yielding ~1 g hydrochloride salt product with >99% purity. Any further purification steps, for example, by column chromatography or recrystallization, were not required.
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Affiliation(s)
- Lars-Erik Meyer
- Biocatalytic Synthesis Group, Institute of Chemistry, University of Rostock, Rostock, Germany
| | | | - Jan von Langermann
- Biocatalytic Synthesis Group, Institute of Chemistry, University of Rostock, Rostock, Germany
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24
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Finnigan W, Citoler J, Cosgrove SC, Turner NJ. Rapid Model-Based Optimization of a Two-Enzyme System for Continuous Reductive Amination in Flow. Org Process Res Dev 2020. [DOI: 10.1021/acs.oprd.0c00075] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- William Finnigan
- Department of Chemistry, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Joan Citoler
- Department of Chemistry, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Sebastian C. Cosgrove
- Future Biomanufacturing Research Hub, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Nicholas J. Turner
- Department of Chemistry, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
- Future Biomanufacturing Research Hub, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
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25
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Montgomery SL, Pushpanath A, Heath RS, Marshall JR, Klemstein U, Galman JL, Woodlock D, Bisagni S, Taylor CJ, Mangas-Sanchez J, Ramsden JI, Dominguez B, Turner NJ. Characterization of imine reductases in reductive amination for the exploration of structure-activity relationships. SCIENCE ADVANCES 2020; 6:eaay9320. [PMID: 32494734 PMCID: PMC7244260 DOI: 10.1126/sciadv.aay9320] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 02/19/2020] [Indexed: 05/16/2023]
Abstract
Imine reductases (IREDs) have shown great potential as catalysts for the asymmetric synthesis of industrially relevant chiral amines, but a limited understanding of sequence activity relationships makes rational engineering challenging. Here, we describe the characterization of 80 putative and 15 previously described IREDs across 10 different transformations and confirm that reductive amination catalysis is not limited to any particular subgroup or sequence motif. Furthermore, we have identified another dehydrogenase subgroup with chemoselectivity for imine reduction. Enantioselectivities were determined for the reduction of the model substrate 2-phenylpiperideine, and the effect of changing the reaction conditions was also studied for the reductive aminations of 1-indanone, acetophenone, and 4-methoxyphenylacetone. We have performed sequence-structure analysis to help explain clusters in activity across a phylogenetic tree and to inform rational engineering, which, in one case, has conferred a change in chemoselectivity that had not been previously observed.
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Affiliation(s)
- Sarah L. Montgomery
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - Ahir Pushpanath
- Johnson Matthey, 28 Cambridge Science Park, Milton Road, Cambridge CB4 0FP, UK
| | - Rachel S. Heath
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - James R. Marshall
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - Ulrike Klemstein
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - James L. Galman
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - David Woodlock
- Johnson Matthey, 28 Cambridge Science Park, Milton Road, Cambridge CB4 0FP, UK
| | - Serena Bisagni
- Johnson Matthey, 28 Cambridge Science Park, Milton Road, Cambridge CB4 0FP, UK
| | - Christopher J. Taylor
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - J. Mangas-Sanchez
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - J. I. Ramsden
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
| | - Beatriz Dominguez
- Johnson Matthey, 28 Cambridge Science Park, Milton Road, Cambridge CB4 0FP, UK
| | - Nicholas J. Turner
- School of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, UK
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26
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Caparco AA, Pelletier E, Petit JL, Jouenne A, Bommarius BR, Berardinis V, Zaparucha A, Champion JA, Bommarius AS, Vergne‐Vaxelaire C. Metagenomic Mining for Amine Dehydrogenase Discovery. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000094] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Adam A. Caparco
- School of Chemical & Biomolecular EngineeringGeorgia Institute of Technology Atlanta, GA USA
| | - Eric Pelletier
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ EvryUniversité Paris-Saclay 91057 Evry France
| | - Jean Louis Petit
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ EvryUniversité Paris-Saclay 91057 Evry France
| | - Aurélie Jouenne
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ EvryUniversité Paris-Saclay 91057 Evry France
| | - Bettina R. Bommarius
- School of Chemical & Biomolecular EngineeringGeorgia Institute of Technology Atlanta, GA USA
| | - Véronique Berardinis
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ EvryUniversité Paris-Saclay 91057 Evry France
| | - Anne Zaparucha
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ EvryUniversité Paris-Saclay 91057 Evry France
| | - Julie A. Champion
- School of Chemical & Biomolecular EngineeringGeorgia Institute of Technology Atlanta, GA USA
| | - Andreas S. Bommarius
- School of Chemical & Biomolecular EngineeringGeorgia Institute of Technology Atlanta, GA USA
| | - Carine Vergne‐Vaxelaire
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ EvryUniversité Paris-Saclay 91057 Evry France
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27
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Zhang YH, Chen FF, Li BB, Zhou XY, Chen Q, Xu JH, Zheng GW. Stereocomplementary Synthesis of Pharmaceutically Relevant Chiral 2-Aryl-Substituted Pyrrolidines Using Imine Reductases. Org Lett 2020; 22:3367-3372. [DOI: 10.1021/acs.orglett.0c00802] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Yu-Hui Zhang
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Fei-Fei Chen
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Bo-Bo Li
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Xin-Yi Zhou
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Qi Chen
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Jian-He Xu
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Gao-Wei Zheng
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
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28
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Yang L, Zhu J, Sun C, Deng Z, Qu X. Biosynthesis of plant tetrahydroisoquinoline alkaloids through an imine reductase route. Chem Sci 2020; 11:364-371. [PMID: 32190259 PMCID: PMC7067268 DOI: 10.1039/c9sc03773j] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 11/17/2019] [Indexed: 01/10/2023] Open
Abstract
Herein, we report a biocatalytic approach to synthesize plant tetrahydroisoquinoline alkaloids (THIQAs) from dihydroisoquinoline (DHIQ) precursors using imine reductases and N-methyltransferase (NMT). The imine reductase IR45 was engineered to significantly expand its substrate specificity, enabling efficient and stereoselective conversion of 1-phenyl and 1-benzyl 6,7-dimethoxy-DHIQs into the corresponding (S)-tetrahydroisoquinolines (S-THIQs). Coclaurine N-methyltransferase (CNMT) was able to further efficiently convert these (S)-THIQ intermediates into (S)-THIQAs. By assembling IRED, CNMT, and glucose dehydrogenase (GDH) in one reaction, we effectively constituted two artificial biosynthetic pathways in Escherichia coli and successfully applied them to the production of five (S)-THIQAs. This highly efficient (100% yield from DHIQs) and easily tailorable (adding other genes) biosynthetic approach will be useful for producing a variety of plant THIQAs.
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Affiliation(s)
- Lu Yang
- State Key Laboratory of Microbial Metabolism , School of Life Sciences and Biotechnology , Shanghai Jiao Tong University , Shanghai 200240 , China .
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education , School of Pharmaceutical Sciences , Wuhan University , Wuhan 430071 , China
| | - Jinmei Zhu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education , School of Pharmaceutical Sciences , Wuhan University , Wuhan 430071 , China
| | - Chenghai Sun
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education , School of Pharmaceutical Sciences , Wuhan University , Wuhan 430071 , China
| | - Zixin Deng
- State Key Laboratory of Microbial Metabolism , School of Life Sciences and Biotechnology , Shanghai Jiao Tong University , Shanghai 200240 , China .
| | - Xudong Qu
- State Key Laboratory of Microbial Metabolism , School of Life Sciences and Biotechnology , Shanghai Jiao Tong University , Shanghai 200240 , China .
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education , School of Pharmaceutical Sciences , Wuhan University , Wuhan 430071 , China
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29
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Megarity CF, Siritanaratkul B, Cheng B, Morello G, Wan L, Sills AJ, Heath RS, Turner NJ, Armstrong FA. Electrified Nanoconfined Biocatalysis with Rapid Cofactor Recycling. ChemCatChem 2019. [DOI: 10.1002/cctc.201901245] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Clare F. Megarity
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | | | - Beichen Cheng
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | - Giorgio Morello
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | - Lei Wan
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | - Adam J. Sills
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
| | - Rachel S. Heath
- School of ChemistryManchester Institute of BiotechnologyUniversity of Manchester 131 Princess Street Manchester M1 7DN UK
| | - Nicholas J. Turner
- School of ChemistryManchester Institute of BiotechnologyUniversity of Manchester 131 Princess Street Manchester M1 7DN UK
| | - Fraser A. Armstrong
- Department of ChemistryUniversity of Oxford South Parks Road Oxford OX1 3QR UK
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30
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Considerations when Measuring Biocatalyst Performance. Molecules 2019; 24:molecules24193573. [PMID: 31623317 PMCID: PMC6804192 DOI: 10.3390/molecules24193573] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 09/27/2019] [Accepted: 09/29/2019] [Indexed: 01/02/2023] Open
Abstract
As biocatalysis matures, it becomes increasingly important to establish methods with which to measure biocatalyst performance. Such measurements are important to assess immobilization strategies, different operating modes, and reactor configurations, aside from comparing protein engineered variants and benchmarking against economic targets. While conventional measurement techniques focus on a single performance metric (such as the total turnover number), here, it is argued that three metrics (achievable product concentration, productivity, and enzyme stability) are required for an accurate assessment of scalability.
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Wu S, Zhou Y, Rebelein JG, Kuhn M, Mallin H, Zhao J, Igareta NV, Ward TR. Breaking Symmetry: Engineering Single-Chain Dimeric Streptavidin as Host for Artificial Metalloenzymes. J Am Chem Soc 2019; 141:15869-15878. [PMID: 31509711 PMCID: PMC6805045 DOI: 10.1021/jacs.9b06923] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
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The biotin–streptavidin technology
has been extensively
exploited to engineer artificial metalloenzymes (ArMs) that catalyze
a dozen different reactions. Despite its versatility, the homotetrameric
nature of streptavidin (Sav) and the noncooperative binding of biotinylated
cofactors impose two limitations on the genetic optimization of ArMs:
(i) point mutations are reflected in all four subunits of Sav, and
(ii) the noncooperative binding of biotinylated cofactors to Sav may
lead to an erosion in the catalytic performance, depending on the
cofactor:biotin-binding site ratio. To address these challenges, we
report on our efforts to engineer a (monovalent) single-chain dimeric
streptavidin (scdSav) as scaffold for Sav-based ArMs. The versatility
of scdSav as host protein is highlighted for the asymmetric transfer
hydrogenation of prochiral imines using [Cp*Ir(biot-p-L)Cl] as cofactor. By capitalizing on a more precise genetic fine-tuning
of the biotin-binding vestibule, unrivaled levels of activity and
selectivity were achieved for the reduction of challenging prochiral
imines. Comparison of the saturation kinetic data and X-ray structures
of [Cp*Ir(biot-p-L)Cl]·scdSav with a structurally
related [Cp*Ir(biot-p-L)Cl]·monovalent scdSav
highlights the advantages of the presence of a single biotinylated
cofactor precisely localized within the biotin-binding vestibule of
the monovalent scdSav. The practicality of scdSav-based ArMs was illustrated
for the reduction of the salsolidine precursor (500 mM) to afford
(R)-salsolidine in 90% ee and >17 000 TONs.
Monovalent scdSav thus provides a versatile scaffold to evolve more
efficient ArMs for in vivo catalysis and large-scale applications.
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Affiliation(s)
- Shuke Wu
- Department of Chemistry , University of Basel , BPR 1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland
| | - Yi Zhou
- Department of Chemistry , University of Basel , BPR 1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland
| | - Johannes G Rebelein
- Department of Chemistry , University of Basel , BPR 1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland
| | - Miriam Kuhn
- Department of Chemistry , University of Basel , BPR 1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland
| | - Hendrik Mallin
- Department of Chemistry , University of Basel , BPR 1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland
| | - Jingming Zhao
- Department of Chemistry , University of Basel , BPR 1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland
| | - Nico V Igareta
- Department of Chemistry , University of Basel , BPR 1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland
| | - Thomas R Ward
- Department of Chemistry , University of Basel , BPR 1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland
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32
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Synthesis of Pluri-Functional Amine Hardeners from Bio-Based Aromatic Aldehydes for Epoxy Amine Thermosets. Molecules 2019; 24:molecules24183285. [PMID: 31505884 PMCID: PMC6766844 DOI: 10.3390/molecules24183285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 08/29/2019] [Accepted: 09/04/2019] [Indexed: 12/17/2022] Open
Abstract
Most of the current amine hardeners are petro-sourced and only a few studies have focused on the research of bio-based substitutes. Hence, in an eco-friendly context, our team proposed the design of bio-based amine monomers with aromatic structures. This work described the use of the reductive amination with imine intermediate in order to obtain bio-based pluri-functional amines exhibiting low viscosity. The effect of the nature of initial aldehyde reactant on the hardener properties was studied, as well as the reaction conditions. Then, these pluri-functional amines were added to petro-sourced (diglycidyl ether of bisphenol A, DGEBA) or bio-based (diglycidyl ether of vanillin alcohol, DGEVA) epoxy monomers to form thermosets by step growth polymerization. Due to their low viscosity, the epoxy-amine mixtures were easily homogenized and cured more rapidly compared to the use of more viscous hardeners (<0.6 Pa s at 22 °C). After curing, the thermo-mechanical properties of the epoxy thermosets were determined and compared. The isophthalatetetramine (IPTA) hardener, with a higher number of amine active H, led to thermosets with higher thermo-mechanical properties (glass transition temperatures (Tg and Tα) were around 95 °C for DGEBA-based thermosets against 60 °C for DGEVA-based thermosets) than materials from benzylamine (BDA) or furfurylamine (FDA) that contained less active hydrogens (Tg and Tα around 77 °C for DGEBA-based thermosets and Tg and Tα around 45 °C for DGEVA-based thermosets). By comparing to industrial hardener references, IPTA possesses six active hydrogens which obtain high cross-linked systems, similar to industrial references, and longer molecular length due to the presence of two alkyl chains, leading respectively to high mechanical strength with lower Tg.
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