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Liu Y, Zhao Z, Song Y, Yin Y, Wu F, Jiang H. Usage of Cell-Free Protein Synthesis in Post-Translational Modification of μ-Conopeptide PIIIA. Mar Drugs 2023; 21:421. [PMID: 37623702 PMCID: PMC10455749 DOI: 10.3390/md21080421] [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: 05/08/2023] [Revised: 07/20/2023] [Accepted: 07/20/2023] [Indexed: 08/26/2023] Open
Abstract
The post-translational modifications of conopeptides are the most complicated modifications to date and are well-known and closely related to the activity of conopeptides. The hydroxylation of proline in conopeptides affects folding, structure, and biological activity, and prolyl 4 hydroxylase has been characterized in Conus literatus. However, the hydroxylation machinery of proline in conopeptides is still unclear. In order to address the hydroxylation mechanism of proline in μ-PIIIA, three recombinant plasmids encoding different hybrid precursors of μ-PIIIA were constructed and crossly combined with protein disulfide isomerase, prolyl 4 hydroxylase, and glutaminyl cyclase in a continuous exchange cell-free protein system. The findings showed that prolyl 4 hydroxylase might recognize the propeptide of μ-PIIIA to achieve the hydroxylation of proline, while the cyclization of glutamate was also formed. Additionally, in Escherichia coli, the co-expression plasmid encoding prolyl 4 hydroxylase and the precursor of μ-PIIIA containing pro and mature regions were used to validate the continuous exchange cell-free protein system. Surprisingly, in addition to the two hydroxyproline residues and one pyroglutamyl residue, three disulfide bridges were formed using Trx as a fusion tag, and the yield of the fusion peptide was approximately 20 mg/L. The results of electrophysiology analysis indicated that the recombinant μ-PIIIA without C-terminal amidate inhibited the current of hNaV1.4 with a 939 nM IC50. Our work solved the issue that it was challenging to quickly generate post-translationally modified conopeptides in vitro. This is the first study to demonstrate that prolyl 4 hydroxylase catalyzes the proline hydroxylation through recognition in the propeptide of μ-PIIIA, and it will provide a new way for synthesizing multi-modified conopeptides with pharmacological activity.
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Affiliation(s)
| | | | | | | | | | - Hui Jiang
- State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China
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2
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Mathur D, Thakur M, Díaz SA, Susumu K, Stewart MH, Oh E, Walper SA, Medintz IL. Hybrid Nucleic Acid-Quantum Dot Assemblies as Multiplexed Reporter Platforms for Cell-Free Transcription Translation-Based Biosensors. ACS Synth Biol 2022; 11:4089-4102. [PMID: 36441919 PMCID: PMC9829448 DOI: 10.1021/acssynbio.2c00394] [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: 11/29/2022]
Abstract
Cell-free synthetic biology has emerged as a valuable tool for the development of rapid, portable biosensors that can be readily transported in the freeze-dried form to the point of need eliminating cold chain requirements. One of the challenges associated with cell-free sensors is the ability to simultaneously detect multiple analytes within a single reaction due to the availability of a limited set of fluorescent and colorimetric reporters. To potentially provide multiplexing capabilities to cell-free biosensors, we designed a modular semiconductor quantum dot (QD)-based reporter platform that is plugged in downstream of the transcription-translation functionality in the cell-free reaction and which converts enzymatic activity in the reaction into distinct optical signals. We demonstrate proof of concept by converting restriction enzyme activity, utilized as our prototypical sensing output, into optical changes across several distinct spectral output channels that all use a common excitation wavelength. These hybrid Förster resonance energy transfer (FRET)-based QD peptide PNA-DNA-Dye reporters (QD-PDDs) are completely self-assembled and consist of differentially emissive QD donors paired to a dye-acceptor displayed on a unique DNA encoding a given enzyme's cleavage site. Three QD-based PDDs, independently activated by the enzymes BamHI, EcoRI, and NcoI, were prototyped in mixed enzyme assays where all three demonstrated the ability to convert enzymatic activity into fluorescent output. Simultaneous monitoring of each of the three paired QD-donor dye-acceptor spectral channels in cell-free biosensing reactions supplemented with added linear genes encoding each enzyme confirmed robust multiplexing capabilities for at least two enzymes when co-expressed. The modular QD-PDDs are easily adapted to respond to other restriction enzymes or even proteases if desired.
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Affiliation(s)
| | | | - Sebastián A. Díaz
- Center for Bio/Molecular Science and Engineering Code 6900, U.S. Naval Research Laboratory, Washington 20375, United States
| | - Kimihiro Susumu
- Jacobs Corporation, Hanover, Maryland 21076, United States; Optical Sciences Division Code 5600, U.S. Naval Research Laboratory, Washington 20375, United States
| | - Michael H. Stewart
- Optical Sciences Division Code 5600, U.S. Naval Research Laboratory, Washington 20375, United States
| | - Eunkeu Oh
- Optical Sciences Division Code 5600, U.S. Naval Research Laboratory, Washington 20375, United States
| | - Scott A. Walper
- Center for Bio/Molecular Science and Engineering Code 6900, U.S. Naval Research Laboratory, Washington 20375, United States
| | - Igor L. Medintz
- Center for Bio/Molecular Science and Engineering Code 6900, U.S. Naval Research Laboratory, Washington 20375, United States
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3
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Multiple Gene Expression in Cell-Free Protein Synthesis Systems for Reconstructing Bacteriophages and Metabolic Pathways. Microorganisms 2022; 10:microorganisms10122477. [PMID: 36557730 PMCID: PMC9786908 DOI: 10.3390/microorganisms10122477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/10/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
As a fast and reliable technology with applications in diverse biological studies, cell-free protein synthesis has become popular in recent decades. The cell-free protein synthesis system can be considered a complex chemical reaction system that is also open to exogenous manipulation, including that which could otherwise potentially harm the cell's viability. On the other hand, since the technology depends on the cell lysates by which genetic information is transformed into active proteins, the whole system resembles the cell to some extent. These features make cell-free protein synthesis a valuable addition to synthetic biology technologies, expediting the design-build-test-learn cycle of synthetic biology routines. While the system has traditionally been used to synthesize one protein product from one gene addition, recent studies have employed multiple gene products in order to, for example, develop novel bacteriophages, viral particles, or synthetic metabolisms. Thus, we would like to review recent advancements in applying cell-free protein synthesis technology to synthetic biology, with an emphasis on multiple gene expressions.
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4
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Opportunities and Challenges of in vitro Synthetic Biosystem for Terpenoids Production. BIOTECHNOL BIOPROC E 2022. [DOI: 10.1007/s12257-022-0100-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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5
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King E, Cui Y, Aspacio D, Nicklen F, Zhang L, Maxel S, Luo R, Siegel JB, Aitchison E, Li H. Engineering Embden-Meyerhof-Parnas Glycolysis to Generate Noncanonical Reducing Power. ACS Catal 2022; 12:8582-8592. [PMID: 37622090 PMCID: PMC10449333 DOI: 10.1021/acscatal.2c01837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Noncanonical cofactors such as nicotinamide mononucleotide (NMN+) supplant the electron-transfer functionality of the natural cofactors, NAD(P)+, at a lower cost in cell-free biomanufacturing and enable orthogonal electron delivery in whole-cell metabolic engineering. Here, we redesign the high-flux Embden-Meyerhof-Parnas (EMP) glycolytic pathway to generate NMN+-based reducing power, by engineering Streptococcus mutans glyceraldehyde-3-phosphate dehydrogenase (Sm GapN) to utilize NMN+. Through iterative rounds of rational design, we discover the variant GapN Penta (P179K-F153S-S330R-I234E-G210Q) with high NMN+-dependent activity and GapN Ortho (P179K-F153S-S330R-I234E-G214E) with ~3.4 × 106-fold switch in cofactor specificity from its native cofactor NADP+ to NMN+. GapN Ortho is further demonstrated to function in Escherichia coli only in the presence of NMN+, enabling orthogonal control of glucose utilization. Molecular dynamics simulation and residue network connectivity analysis indicate that mutations altering cofactor specificity must be coordinated to maintain the appropriate degree of backbone flexibility to position the catalytic cysteine. These results provide a strategy to guide future designs of NMN+-dependent enzymes and establish the initial steps toward an orthogonal EMP pathway with biomanufacturing potential.
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Affiliation(s)
- Edward King
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Youtian Cui
- Genome Center, University of California, Davis, Davis, California 95616, United States
| | - Derek Aspacio
- Department of Chemical and Biomolecular Engineering, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Frances Nicklen
- Department of Biomedical Engineering, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Linyue Zhang
- Department of Chemical and Biomolecular Engineering, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Sarah Maxel
- Department of Chemical and Biomolecular Engineering, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Ray Luo
- Department of Molecular Biology and Biochemistry, Department of Chemical and Biomolecular Engineering, and Department of Biomedical Engineering, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Justin B Siegel
- Department of Chemistry, Genome Center, and Department of Biochemistry and Molecular Medicine, University of California, Davis, Davis, California 95616, United States
| | - Erick Aitchison
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Han Li
- Department of Chemical and Biomolecular Engineering and Department of Biomedical Engineering, University of California, Irvine, Irvine, California 92697-3900, United States
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6
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Jew K, Smith PEJ, So B, Kasman J, Oza JP, Black MW. Characterizing and Improving pET Vectors for Cell-free Expression. Front Bioeng Biotechnol 2022; 10:895069. [PMID: 35814024 PMCID: PMC9259831 DOI: 10.3389/fbioe.2022.895069] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 05/26/2022] [Indexed: 11/15/2022] Open
Abstract
Cell-free protein synthesis (CFPS) is an in vitro process that enables diverse applications in research, biomanufacturing, point-of-care diagnostics, therapeutics, and education using minimal laboratory equipment and reagents. One of the major limitations of CFPS implementation is its sensitivity to plasmid type. Specifically, plasmid templates based on commonly used vector backbones such as the pET series of bacterial expression vectors result in the inferior production of proteins. To overcome this limitation, we have evaluated the effect of expression cassette elements present in the pET30 vector on protein production across three different CFPS systems: NEBExpress, PURExpress, and CFAI-based E. coli extracts. Through the systematic elimination of genetic elements within the pET30 vector, we have identified elements that are responsible for the poor performance of pET30 vectors in the various CFPS systems. As a result, we demonstrate that through the removal of the lac operator (lacO) and N-terminal tags included in the vector backbone sequence, a pET vector can support high titers of protein expression when using extract-based CFPS systems. This work provides two key advances for the research community: 1) identification of vector sequence elements that affect robust production of proteins; 2) evaluation of expression across three unique CFPS systems including CFAI extracts, NEBexpress, and PURExpress. We anticipate that this work will improve access to CFPS by enabling researchers to choose the correct expression backbone within the context of their preferred expression system.
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Affiliation(s)
- Kara Jew
- Biological Sciences Department, California Polytechnic State University, San Luis Obispo, CA, United States
| | - Philip E. J. Smith
- Chemistry & Biochemistry Department, California Polytechnic State University, San Luis Obispo, CA, United States
| | - Byungcheol So
- Chemistry & Biochemistry Department, California Polytechnic State University, San Luis Obispo, CA, United States
| | - Jillian Kasman
- Chemistry & Biochemistry Department, California Polytechnic State University, San Luis Obispo, CA, United States
| | - Javin P. Oza
- Chemistry & Biochemistry Department, California Polytechnic State University, San Luis Obispo, CA, United States
- *Correspondence: Javin P. Oza, ; Michael W. Black,
| | - Michael W. Black
- Biological Sciences Department, California Polytechnic State University, San Luis Obispo, CA, United States
- *Correspondence: Javin P. Oza, ; Michael W. Black,
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7
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Rasor BJ, Vögeli B, Jewett MC, Karim AS. Cell-Free Protein Synthesis for High-Throughput Biosynthetic Pathway Prototyping. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2433:199-215. [PMID: 34985746 DOI: 10.1007/978-1-0716-1998-8_12] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Biological systems provide a sustainable and complimentary approach to synthesizing useful chemical products. Metabolic engineers seeking to establish economically viable biosynthesis platforms strive to increase product titers, rates, and yields. Despite continued advances in genetic tools and metabolic engineering techniques, cellular workflows remain limited in throughput. It may take months to test dozens of unique pathway designs even in a robust model organism, such as Escherichia coli. In contrast, cell-free protein synthesis enables the rapid generation of enzyme libraries that can be combined to reconstitute metabolic pathways in vitro for biochemical synthesis in days rather than weeks. Cell-free reactions thereby enable comparison of hundreds to thousands of unique combinations of enzyme homologs and concentrations, which can quickly identify the most productive pathway variants to test in vivo or further characterize in vitro. This cell-free pathway prototyping strategy provides a complementary approach to accelerate cellular metabolic engineering efforts toward highly productive strains for metabolite production.
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Affiliation(s)
- Blake J Rasor
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, USA.,Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA.,Center for Synthetic Biology, Northwestern University, Evanston, IL, USA
| | - Bastian Vögeli
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, USA.,Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, USA.,Center for Synthetic Biology, Northwestern University, Evanston, IL, USA
| | - Michael C Jewett
- Department of Chemical and Biological Engineering, Chemistry of Life Processes Institute, Center for Synthetic Biology, Robert H. Lurie Comprehensive Cancer Center, and Simpson Querrey Institute, Northwestern University, Evanston, IL, USA.
| | - Ashty S Karim
- Department of Chemical and Biological Engineering, Chemistry of Life Processes Institute, and Center for Synthetic Biology, Northwestern University, Evanston, IL, USA.
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8
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Key reaction components affect the kinetics and performance robustness of cell-free protein synthesis reactions. Comput Struct Biotechnol J 2022; 20:218-229. [PMID: 35024094 PMCID: PMC8718664 DOI: 10.1016/j.csbj.2021.12.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 12/08/2021] [Accepted: 12/08/2021] [Indexed: 11/23/2022] Open
Abstract
Novel cell-free protein synthesis reaction buffer improves performance by 400%. Enhanced performance is maintained across the synthesis of different proteins. Protein synthesis performance is robust across different cell lysate batches and E. coli strains. Buffer components affect aspects of reaction kinetics in differing ways.
Cell-free protein synthesis (CFPS) reactions have grown in popularity with particular interest in applications such as gene construct prototyping, biosensor technologies and the production of proteins with novel chemistry. Work has frequently focussed on optimising CFPS protocols for improving protein yield, reducing cost, or developing streamlined production protocols. Here we describe a statistical Design of Experiments analysis of 20 components of a popular CFPS reaction buffer. We simultaneously identify factors and factor interactions that impact on protein yield, rate of reaction, lag time and reaction longevity. This systematic experimental approach enables the creation of a statistical model capturing multiple behaviours of CFPS reactions in response to components and their interactions. We show that a novel reaction buffer outperforms the reference reaction by 400% and importantly reduces failures in CFPS across batches of cell lysates, strains of E. coli, and in the synthesis of different proteins. Detailed and quantitative understanding of how reaction components affect kinetic responses and robustness is imperative for future deployment of cell-free technologies.
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Key Words
- 3-PGA, 3-phosphoglyceric acid
- ATP, adenosine triphosphate
- Automation
- CFE, cell-free extract
- CFPS, cell-free protein synthesis
- CTP, cytidine triphosphate
- Cell-free protein synthesis (CFPS)
- CoA, coenzyme A
- DSD, Definitive Screening Design
- DTT, dithiothreitol
- Design of Experiments (DoE)
- DoE, Design of Experiments
- FEU, fluorescein equivalent units
- G-6-P, glucose-6-phosphate
- GTP, guanosine triphosphate
- HEPES, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid
- K-glutamate, potassium glutamate
- LB, lysogeny broth
- Mg, magnesium glutamate
- NAD, nicotinamide adenine dinucleotide
- NTP, nucleoside triphosphate
- OFAT, one-factor-at-a-time
- PEG-8000, polyethylene glycol 8000
- PEP, phosphoenolpyruvate
- RFU, relative fluorescence units
- RSM, Response Surface Model
- Robustness
- Statistical engineering
- UTP, uridine triphosphate
- X-gal, 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside
- cAMP, cyclic adenosine monophosphate
- eGFP, enhanced green fluorescent protein
- tRNA, transfer ribonucleic acid
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9
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Brookwell A, Oza JP, Caschera F. Biotechnology Applications of Cell-Free Expression Systems. Life (Basel) 2021; 11:life11121367. [PMID: 34947898 PMCID: PMC8705439 DOI: 10.3390/life11121367] [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: 11/11/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 12/13/2022] Open
Abstract
Cell-free systems are a rapidly expanding platform technology with an important role in the engineering of biological systems. The key advantages that drive their broad adoption are increased efficiency, versatility, and low cost compared to in vivo systems. Traditionally, in vivo platforms have been used to synthesize novel and industrially relevant proteins and serve as a testbed for prototyping numerous biotechnologies such as genetic circuits and biosensors. Although in vivo platforms currently have many applications within biotechnology, they are hindered by time-constraining growth cycles, homeostatic considerations, and limited adaptability in production. Conversely, cell-free platforms are not hindered by constraints for supporting life and are therefore highly adaptable to a broad range of production and testing schemes. The advantages of cell-free platforms are being leveraged more commonly by the biotechnology community, and cell-free applications are expected to grow exponentially in the next decade. In this study, new and emerging applications of cell-free platforms, with a specific focus on cell-free protein synthesis (CFPS), will be examined. The current and near-future role of CFPS within metabolic engineering, prototyping, and biomanufacturing will be investigated as well as how the integration of machine learning is beneficial to these applications.
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Affiliation(s)
- August Brookwell
- Department of Chemistry & Biochemistry, College of Science & Mathematics, California Polytechnic State University, San Luis Obispo, CA 93407, USA;
| | - Javin P. Oza
- Department of Chemistry & Biochemistry, College of Science & Mathematics, California Polytechnic State University, San Luis Obispo, CA 93407, USA;
- Correspondence: (J.P.O.); (F.C.)
| | - Filippo Caschera
- Nuclera Nucleics Ltd., Cambridge CB4 0GD, UK
- Correspondence: (J.P.O.); (F.C.)
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10
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Kinetic modelling of 2,3-butanediol production by Raoultella terrigena CECT 4519 resting cells: Effect of fluid dynamics conditions and initial glycerol concentration. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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11
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An integrated in vivo/in vitro framework to enhance cell-free biosynthesis with metabolically rewired yeast extracts. Nat Commun 2021; 12:5139. [PMID: 34446711 PMCID: PMC8390474 DOI: 10.1038/s41467-021-25233-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 07/30/2021] [Indexed: 02/07/2023] Open
Abstract
Cell-free systems using crude cell extracts present appealing opportunities for designing biosynthetic pathways and enabling sustainable chemical synthesis. However, the lack of tools to effectively manipulate the underlying host metabolism in vitro limits the potential of these systems. Here, we create an integrated framework to address this gap that leverages cell extracts from host strains genetically rewired by multiplexed CRISPR-dCas9 modulation and other metabolic engineering techniques. As a model, we explore conversion of glucose to 2,3-butanediol in extracts from flux-enhanced Saccharomyces cerevisiae strains. We show that cellular flux rewiring in several strains of S. cerevisiae combined with systematic optimization of the cell-free reaction environment significantly increases 2,3-butanediol titers and volumetric productivities, reaching productivities greater than 0.9 g/L-h. We then show the generalizability of the framework by improving cell-free itaconic acid and glycerol biosynthesis. Our coupled in vivo/in vitro metabolic engineering approach opens opportunities for synthetic biology prototyping efforts and cell-free biomanufacturing.
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12
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Blum SM, Lee MS, Mgboji GE, Funk VL, Beabout K, Harbaugh SV, Roth PA, Liem AT, Miklos AE, Emanuel PA, Walper SA, Chávez JL, Lux MW. Impact of Porous Matrices and Concentration by Lyophilization on Cell-Free Expression. ACS Synth Biol 2021; 10:1116-1131. [PMID: 33843211 DOI: 10.1021/acssynbio.0c00634] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Cell-free expression systems have drawn increasing attention as a tool to achieve complex biological functions outside of the cell. Several applications of the technology involve the delivery of functionality to challenging environments, such as field-forward diagnostics or point-of-need manufacturing of pharmaceuticals. To achieve these goals, cell-free reaction components are preserved using encapsulation or lyophilization methods, both of which often involve an embedding of components in porous matrices like paper or hydrogels. Previous work has shown a range of impacts of porous materials on cell-free expression reactions. Here, we explored a panel of 32 paperlike materials and 5 hydrogel materials for the impact on reaction performance. The screen included a tolerance to lyophilization for reaction systems based on both cell lysates and purified expression components. For paperlike materials, we found that (1) materials based on synthetic polymers were mostly incompatible with cell-free expression, (2) lysate-based reactions were largely insensitive to the matrix for cellulosic and microfiber materials, and (3) purified systems had an improved performance when lyophilized in cellulosic but not microfiber matrices. The impact of hydrogel materials ranged from completely inhibitory to a slight enhancement. The exploration of modulating the rehydration volume of lyophilized reactions yielded reaction speed increases using an enzymatic colorimetric reporter of up to twofold with an optimal ratio of 2:1 lyophilized reaction to rehydration volume for the lysate system and 1.5:1 for the purified system. The effect was independent of the matrices assessed. Testing with a fluorescent nonenzymatic reporter and no matrix showed similar improvements in both yields and reaction speeds for the lysate system and yields but not reaction speeds for the purified system. We finally used these observations to show an improved performance of two sensors that span reaction types, matrix, and reporters. In total, these results should enhance efforts to develop field-forward applications of cell-free expression systems.
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Affiliation(s)
- Steven M. Blum
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
| | - Marilyn S. Lee
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
| | - Glory E. Mgboji
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37830-6209, United States
| | - Vanessa L. Funk
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
| | - Kathryn Beabout
- UES, Inc., Dayton, Ohio 45432, United States
- 711th Human Performance Wing, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Svetlana V. Harbaugh
- 711th Human Performance Wing, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Pierce A. Roth
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
- DCS Corporation, 4696 Millenium Drive, Suite 450, Belcamp, Maryland 21017, United States
| | - Alvin T. Liem
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
- DCS Corporation, 4696 Millenium Drive, Suite 450, Belcamp, Maryland 21017, United States
| | - Aleksandr E. Miklos
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
| | - Peter A. Emanuel
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
| | - Scott A. Walper
- Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, District of Columbia 20375, United States
| | - Jorge Luis Chávez
- 711th Human Performance Wing, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Matthew W. Lux
- United States Army Combat Capabilities Development Command Chemical Biological Center. 8198 Blackhawk Road, APG, Aberdeen, Maryland 21010, United States
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Batista AC, Soudier P, Kushwaha M, Faulon J. Optimising protein synthesis in cell‐free systems, a review. ENGINEERING BIOLOGY 2021; 5:10-19. [PMID: 36968650 PMCID: PMC9996726 DOI: 10.1049/enb2.12004] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 12/03/2020] [Accepted: 12/09/2020] [Indexed: 12/25/2022] Open
Abstract
Over the last decades, cell-free systems have been extensively used for in vitro protein expression. A vast range of protocols and cellular sources varying from prokaryotes and eukaryotes are now available for cell-free technology. However, exploiting the maximum capacity of cell free systems is not achieved by using traditional protocols. Here, what are the strategies and choices one can apply to optimise cell-free protein synthesis have been reviewed. These strategies provide robust and informative improvements regarding transcription, translation and protein folding which can later be used for the establishment of individual best cell-free reactions per lysate batch.
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Affiliation(s)
- Angelo C. Batista
- Université Paris‐Saclay INRAE AgroParisTech Micalis Institute Jouy‐en‐Josas France
| | - Paul Soudier
- Université Paris‐Saclay INRAE AgroParisTech Micalis Institute Jouy‐en‐Josas France
| | - Manish Kushwaha
- Université Paris‐Saclay INRAE AgroParisTech Micalis Institute Jouy‐en‐Josas France
| | - Jean‐Loup Faulon
- Université Paris‐Saclay INRAE AgroParisTech Micalis Institute Jouy‐en‐Josas France
- SYNBIOCHEM Center School of Chemistry Manchester Institute of Biotechnology The University of Manchester Manchester UK
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14
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Reyes SG, Kuruma Y, Fujimi M, Yamazaki M, Eto S, Nishikawa S, Tamaki S, Kobayashi A, Mizuuchi R, Rothschild L, Ditzler M, Fujishima K. PURE mRNA display and cDNA display provide rapid detection of core epitope motif via high-throughput sequencing. Biotechnol Bioeng 2021; 118:1736-1749. [PMID: 33501662 DOI: 10.1002/bit.27696] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 01/02/2021] [Accepted: 01/17/2021] [Indexed: 12/17/2022]
Abstract
The reconstructed in vitro translation system known as the PURE system has been used in a variety of cell-free experiments such as the expression of native and de novo proteins as well as various display methods to select for functional polypeptides. We developed a refined PURE-based display method for the preparation of stable messenger RNA (mRNA) and complementary DNA (cDNA)-peptide conjugates and validated its utility for in vitro selection. Our conjugate formation efficiency exceeded 40%, followed by gel purification to allow minimum carry-over of components from the translation system to the downstream assay enabling clean and efficient random peptide sequence screening. We chose the commercially available anti-FLAG M2 antibody as a target molecule for validation. Starting from approximately 1.7 × 1012 random sequences, a round-by-round high-throughput sequencing showed clear enrichment of the FLAG epitope DYKDDD as well as revealing consensus FLAG epitope motif DYK(D/L/N)(L/Y/D/N/F)D. Enrichment of core FLAG motifs lacking one of the four key residues (DYKxxD) indicates that Tyr (Y) and Lys (K) appear as the two key residues essential for binding. Furthermore, the comparison between mRNA display and cDNA display method resulted in overall similar performance with slightly higher enrichment for mRNA display. We also show that gel purification steps in the refined PURE-based display method improve conjugate formation efficiency and enhance the enrichment rate of FLAG epitope motifs in later rounds of selection especially for mRNA display. Overall, the generalized procedure and consistent performance of two different display methods achieved by the commercially available PURE system will be useful for future studies to explore the sequence and functional space of diverse polypeptides.
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Affiliation(s)
- Sabrina Galiñanes Reyes
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan.,Extra-cutting-edge Science and Technology Avant-garde Research Program, Japan Agency for Marine-Earth Science and Technology, Kanagawa, Japan.,James Watt School of Engineering, The University of Glasgow, Glasgow, UK
| | - Yutetsu Kuruma
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan.,Extra-cutting-edge Science and Technology Avant-garde Research Program, Japan Agency for Marine-Earth Science and Technology, Kanagawa, Japan.,JST, PRESTO, Saitama, Japan
| | - Mai Fujimi
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
| | | | - Sumie Eto
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan.,MOLCURE Inc., Shinagawa, Tokyo, Japan
| | - Shota Nishikawa
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan.,School of Life Science and Technology, Tokyo Institute of Technology, Tokyo, Japan
| | | | - Asaki Kobayashi
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, Evry, France
| | - Ryo Mizuuchi
- JST, PRESTO, Saitama, Japan.,Komaba Institute for Science, The University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Lynn Rothschild
- Center for the Emergence of Life, NASA Ames Research Center, Moffett Field, California, USA
| | - Mark Ditzler
- Center for the Emergence of Life, NASA Ames Research Center, Moffett Field, California, USA
| | - Kosuke Fujishima
- Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan.,Graduate School of Media and Governance, Keio University, Fujisawa, Japan
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15
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Toward sustainable, cell-free biomanufacturing. Curr Opin Biotechnol 2021; 69:136-144. [PMID: 33453438 DOI: 10.1016/j.copbio.2020.12.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 12/10/2020] [Accepted: 12/15/2020] [Indexed: 12/12/2022]
Abstract
Industrial biotechnology is an attractive approach to address the need for low-cost fuels and products from sustainable resources. Unfortunately, cells impose inherent limitations on the effective synthesis and release of target products. One key constraint is that cellular survival objectives often work against the production objectives of biochemical engineers. Additionally, industrial strains release CO2 and struggle to utilize sustainable, potentially profitable feedstocks. Cell-free biotechnology, which uses biological machinery harvested from cells, can address these challenges with advantages including: (i) shorter development times, (ii) higher volumetric production rates, and (iii) tolerance to otherwise toxic molecules. In this review, we highlight recent advances in cell-free technologies toward the production of non-protein products beyond lab-scale demonstrations and describe guiding principles for designing cell-free systems. Specifically, we discuss carbon and energy sources, reaction homeostasis, and scale-up. Expanding the scope of cell-free biomanufacturing practice could enable innovative approaches for the industrial production of green chemicals.
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16
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Lee MS, Raig RM, Gupta MK, Lux MW. Lyophilized Cell-Free Systems Display Tolerance to Organic Solvent Exposure. ACS Synth Biol 2020; 9:1951-1957. [PMID: 32646213 DOI: 10.1021/acssynbio.0c00267] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cell-free systems offer a powerful way to deliver biochemical activity to the field without cold chain storage. These systems are capable of sensing as well as biosynthesis of useful molecules at the point of need. So far, cell-free protein synthesis (CFPS) reactions have been studied as aqueous solutions in test tubes or absorbed into paper or cloth. Embedding biological functionality into broadly used materials, such as plastic polymers, represents an attractive goal. Unfortunately, this goal has for the most part remained out of reach, presumably due to the fragility of biological systems outside of aqueous environments. Here, we describe a surprising and useful feature of lyophilized cell-free lysate systems: tolerance to a variety of organic solvents. Screens of individual CFPS reagents and different CFPS methods reveal that solvent tolerance varies by CFPS reagent composition. Tolerance to suspension in organic solvents may facilitate the use of polymers to deliver dry cell-free reactions in the form of coatings or fibers, or allow dosing of analytes or substrates dissolved in nonaqueous solvents, among other processing possibilities.
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Affiliation(s)
- Marilyn S. Lee
- US Army Combat Capabilities Development Command Chemical and Biological Center, 8567 Ricketts Point Road, Aberdeen Proving Ground, Maryland 21010, United States
| | - Rebecca M. Raig
- US Air Force Research Laboratory, 2179 12th Street, B652/R122 Wright-Patterson Air Force Base, Ohio 45433, United States
- UES Inc., 4401 Dayton-Xenia Road, Dayton, Ohio 45432, United States
| | - Maneesh K. Gupta
- US Air Force Research Laboratory, 2179 12th Street, B652/R122 Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Matthew W. Lux
- US Army Combat Capabilities Development Command Chemical and Biological Center, 8567 Ricketts Point Road, Aberdeen Proving Ground, Maryland 21010, United States
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17
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Richardson KN, Black WB, Li H. Aldehyde Production in Crude Lysate- and Whole Cell-Based Biotransformation Using a Noncanonical Redox Cofactor System. ACS Catal 2020; 10:8898-8903. [PMID: 34306803 DOI: 10.1021/acscatal.0c03070] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
It is challenging to biosynthesize industrially important aldehydes, which are readily consumed by the numerous alcohol dehydrogenases (ADHs) in cells. In this work, we demonstrate that a nicotinamide mononucleotide (NMN+)-dependent redox cofactor cycling system enables aldehyde accumulation in Escherichia coli crude lysates and whole cells. By specifically delivering reducing power to a recombinant enoate reductase, but not to endogenous ADHs, we convert citral to citronellal with minimal byproduct formation (97-100% and 83% product purity in crude lysate- and whole cell-based biotransformation, respectively). We envision the system's universal application to lowering the noise in biomanufacturing by silencing the host's metabolic background.
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Affiliation(s)
- Kelly N. Richardson
- Department of Chemical and Biomolecular Engineering, University of California Irvine, Irvine, California 92697-2700, United States
| | - William B. Black
- Department of Chemical and Biomolecular Engineering, University of California Irvine, Irvine, California 92697-2700, United States
| | - Han Li
- Department of Chemical and Biomolecular Engineering, University of California Irvine, Irvine, California 92697-2700, United States
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18
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Jaroentomeechai T, Taw MN, Li M, Aquino A, Agashe N, Chung S, Jewett MC, DeLisa MP. Cell-Free Synthetic Glycobiology: Designing and Engineering Glycomolecules Outside of Living Cells. Front Chem 2020; 8:645. [PMID: 32850660 PMCID: PMC7403607 DOI: 10.3389/fchem.2020.00645] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 06/22/2020] [Indexed: 12/12/2022] Open
Abstract
Glycans and glycosylated biomolecules are directly involved in almost every biological process as well as the etiology of most major diseases. Hence, glycoscience knowledge is essential to efforts aimed at addressing fundamental challenges in understanding and improving human health, protecting the environment and enhancing energy security, and developing renewable and sustainable resources that can serve as the source of next-generation materials. While much progress has been made, there remains an urgent need for new tools that can overexpress structurally uniform glycans and glycoconjugates in the quantities needed for characterization and that can be used to mechanistically dissect the enzymatic reactions and multi-enzyme assembly lines that promote their construction. To address this technology gap, cell-free synthetic glycobiology has emerged as a simplified and highly modular framework to investigate, prototype, and engineer pathways for glycan biosynthesis and biomolecule glycosylation outside the confines of living cells. From nucleotide sugars to complex glycoproteins, we summarize here recent efforts that harness the power of cell-free approaches to design, build, test, and utilize glyco-enzyme reaction networks that produce desired glycomolecules in a predictable and controllable manner. We also highlight novel cell-free methods for shedding light on poorly understood aspects of diverse glycosylation processes and engineering these processes toward desired outcomes. Taken together, cell-free synthetic glycobiology represents a promising set of tools and techniques for accelerating basic glycoscience research (e.g., deciphering the "glycan code") and its application (e.g., biomanufacturing high-value glycomolecules on demand).
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Affiliation(s)
- Thapakorn Jaroentomeechai
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
| | - May N. Taw
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
| | - Mingji Li
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
| | - Alicia Aquino
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
| | - Ninad Agashe
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
| | - Sean Chung
- Graduate Field of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY, United States
| | - Michael C. Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, United States
- Center for Synthetic Biology, Northwestern University, Evanston, IL, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL, United States
| | - Matthew P. DeLisa
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, United States
- Graduate Field of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY, United States
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19
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Black WB, Aspacio D, Bever D, King E, Zhang L, Li H. Metabolic engineering of Escherichia coli for optimized biosynthesis of nicotinamide mononucleotide, a noncanonical redox cofactor. Microb Cell Fact 2020; 19:150. [PMID: 32718347 PMCID: PMC7384224 DOI: 10.1186/s12934-020-01415-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 07/20/2020] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Noncanonical redox cofactors are emerging as important tools in cell-free biosynthesis to increase the economic viability, to enable exquisite control, and to expand the range of chemistries accessible. However, these noncanonical redox cofactors need to be biologically synthesized to achieve full integration with renewable biomanufacturing processes. RESULTS In this work, we engineered Escherichia coli cells to biosynthesize the noncanonical cofactor nicotinamide mononucleotide (NMN+), which has been efficiently used in cell-free biosynthesis. First, we developed a growth-based screening platform to identify effective NMN+ biosynthetic pathways in E. coli. Second, we explored various pathway combinations and host gene disruption to achieve an intracellular level of ~ 1.5 mM NMN+, a 130-fold increase over the cell's basal level, in the best strain, which features a previously uncharacterized nicotinamide phosphoribosyltransferase (NadV) from Ralstonia solanacearum. Last, we revealed mechanisms through which NMN+ accumulation impacts E. coli cell fitness, which sheds light on future work aiming to improve the production of this noncanonical redox cofactor. CONCLUSION These results further the understanding of effective production and integration of NMN+ into E. coli. This may enable the implementation of NMN+-directed biocatalysis without the need for exogenous cofactor supply.
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Affiliation(s)
- William B Black
- Departments of Chemical and Biomolecular Engineering, University of California, Irvine, CA, United States
| | - Derek Aspacio
- Departments of Chemical and Biomolecular Engineering, University of California, Irvine, CA, United States
| | - Danielle Bever
- Departments of Chemical and Biomolecular Engineering, University of California, Irvine, CA, United States
| | - Edward King
- Molecular Biology and Biochemistry, University of California, Irvine, CA, United States
| | - Linyue Zhang
- Departments of Chemical and Biomolecular Engineering, University of California, Irvine, CA, United States
| | - Han Li
- Departments of Chemical and Biomolecular Engineering, University of California, Irvine, CA, United States.
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20
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Development of a clostridia-based cell-free system for prototyping genetic parts and metabolic pathways. Metab Eng 2020; 62:95-105. [PMID: 32540392 DOI: 10.1016/j.ymben.2020.06.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/15/2020] [Accepted: 06/07/2020] [Indexed: 02/04/2023]
Abstract
Gas fermentation by autotrophic bacteria, such as clostridia, offers a sustainable path to numerous bioproducts from a range of local, highly abundant, waste and low-cost feedstocks, such as industrial flue gases or syngas generated from biomass or municipal waste. Unfortunately, designing and engineering clostridia remains laborious and slow. The ability to prototype individual genetic part function, gene expression patterns, and biosynthetic pathway performance in vitro before implementing designs in cells could help address these bottlenecks by speeding up design. Unfortunately, a high-yielding cell-free gene expression (CFE) system from clostridia has yet to be developed. Here, we report the development and optimization of a high-yielding (236 ± 24 μg/mL) batch CFE platform from the industrially relevant anaerobe, Clostridium autoethanogenum. A key feature of the platform is that both circular and linear DNA templates can be applied directly to the CFE reaction to program protein synthesis. We demonstrate the ability to prototype gene expression, and quantitatively map aerobic cell-free metabolism in lysates from this system. We anticipate that the C. autoethanogenum CFE platform will not only expand the protein synthesis toolkit for synthetic biology, but also serve as a platform in expediting the screening and prototyping of gene regulatory elements in non-model, industrially relevant microbes.
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21
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Kelwick RJR, Webb AJ, Freemont PS. Biological Materials: The Next Frontier for Cell-Free Synthetic Biology. Front Bioeng Biotechnol 2020; 8:399. [PMID: 32478045 PMCID: PMC7235315 DOI: 10.3389/fbioe.2020.00399] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 04/08/2020] [Indexed: 12/13/2022] Open
Abstract
Advancements in cell-free synthetic biology are enabling innovations in sustainable biomanufacturing, that may ultimately shift the global manufacturing paradigm toward localized and ecologically harmonized production processes. Cell-free synthetic biology strategies have been developed for the bioproduction of fine chemicals, biofuels and biological materials. Cell-free workflows typically utilize combinations of purified enzymes, cell extracts for biotransformation or cell-free protein synthesis reactions, to assemble and characterize biosynthetic pathways. Importantly, cell-free reactions can combine the advantages of chemical engineering with metabolic engineering, through the direct addition of co-factors, substrates and chemicals -including those that are cytotoxic. Cell-free synthetic biology is also amenable to automatable design cycles through which an array of biological materials and their underpinning biosynthetic pathways can be tested and optimized in parallel. Whilst challenges still remain, recent convergences between the materials sciences and these advancements in cell-free synthetic biology enable new frontiers for materials research.
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Affiliation(s)
- Richard J. R. Kelwick
- Section of Structural and Synthetic Biology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Alexander J. Webb
- Section of Structural and Synthetic Biology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Paul S. Freemont
- Section of Structural and Synthetic Biology, Department of Infectious Disease, Imperial College London, London, United Kingdom
- The London Biofoundry, Imperial College Translation & Innovation Hub, London, United Kingdom
- UK Dementia Research Institute Care Research and Technology Centre, Imperial College London, London, United Kingdom
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