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Ekas HM, Wang B, Silverman AD, Lucks JB, Karim AS, Jewett MC. An Automated Cell-Free Workflow for Transcription Factor Engineering. ACS Synth Biol 2024; 13:3389-3399. [PMID: 39373325 DOI: 10.1021/acssynbio.4c00471] [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] [Indexed: 10/08/2024]
Abstract
The design and optimization of metabolic pathways, genetic systems, and engineered proteins rely on high-throughput assays to streamline design-build-test-learn cycles. However, assay development is a time-consuming and laborious process. Here, we create a generalizable approach for the tailored optimization of automated cell-free gene expression (CFE)-based workflows, which offers distinct advantages over in vivo assays in reaction flexibility, control, and time to data. Centered around designing highly accurate and precise transfers on the Echo Acoustic Liquid Handler, we introduce pilot assays and validation strategies for each stage of protocol development. We then demonstrate the efficacy of our platform by engineering transcription factor-based biosensors. As a model, we rapidly generate and assay libraries of 127 MerR and 134 CadR transcription factor variants in 3682 unique CFE reactions in less than 48 h to improve limit of detection, selectivity, and dynamic range for mercury and cadmium detection. This was achieved by assessing a panel of ligand conditions for sensitivity (to 0.1, 1, 10 μM Hg and 0, 1, 10, 100 μM Cd for MerR and CadR, respectively) and selectivity (against Ag, As, Cd, Co, Cu, Hg, Ni, Pb, and Zn). We anticipate that our Echo-based, cell-free approach can be used to accelerate multiple design workflows in synthetic biology.
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Affiliation(s)
- Holly M Ekas
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Brenda Wang
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Adam D Silverman
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Julius B Lucks
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
- Center for Engineering Sustainability and Resilience, Northwestern University, Evanston, Illinois 60208, United States
| | - Ashty S Karim
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Michael C Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
- Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois 60611, United States
- Simpson Querrey Institute, Northwestern University, Chicago, Illinois 60611, United States
- Department of Bioengineering, Stanford University, Stanford, California 94305, United States
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2
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Schloßhauer JL, Tholen L, Körner A, Kubick S, Chatzopoulou S, Hönow A, Zemella A. Promoting the production of challenging proteins via induced expression in CHO cells and modified cell-free lysates harboring T7 RNA polymerase and mutant eIF2α. Synth Syst Biotechnol 2024; 9:416-424. [PMID: 38601208 PMCID: PMC11004649 DOI: 10.1016/j.synbio.2024.03.011] [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: 12/08/2023] [Revised: 02/12/2024] [Accepted: 03/16/2024] [Indexed: 04/12/2024] Open
Abstract
Chinese hamster ovary (CHO) cells are crucial in biopharmaceutical production due to their scalability and capacity for human-like post-translational modifications. However, toxic proteins and membrane proteins are often difficult-to-express in living cells. Alternatively, cell-free protein synthesis can be employed. This study explores innovative strategies for enhancing the production of challenging proteins through the modification of CHO cells by investigating both, cell-based and cell-free approaches. A major result in our study involves the integration of a mutant eIF2 translation initiation factor and T7 RNA polymerase into CHO cell lysates for cell-free protein synthesis. This resulted in elevated yields, while eliminating the necessity for exogenous additions during cell-free production, thereby substantially enhancing efficiency. Additionally, we explore the potential of the Rosa26 genomic site for the integration of T7 RNA polymerase and cell-based tetracycline-controlled protein expression. These findings provide promising advancements in bioproduction technologies, offering flexibility to switch between cell-free and cell-based protein production as needed.
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Affiliation(s)
- Jeffrey L. Schloßhauer
- Fraunhofer Project Group PZ-Syn of the Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
- Institute for Chemistry and Biochemistry, Laboratory of Protein Biochemistry, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - Lena Tholen
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
| | - Alexander Körner
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
- Institute of Biotechnology, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Stefan Kubick
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus –Senftenberg, The Brandenburg Medical School Theodor Fontane, University of Potsdam, Potsdam, Germany
- Institute for Chemistry and Biochemistry, Laboratory of Protein Biochemistry, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - Sofia Chatzopoulou
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
| | - Anja Hönow
- New/era/mabs GmbH, August-Bebel-Str. 89, 14482, Potsdam, Germany
| | - Anne Zemella
- Fraunhofer Institute for Cell Therapy and Immunology-IZI, Branch Bioanalytics and Bioprocesses-IZI-BB, Am Mühlenberg, Potsdam, Germany
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3
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Zhang Z, Li J, Chen C, Tong Y, Liu D, Li C, Lu H, Huang L, Feng W, Sun X. Exploring T7 RNA polymerase-assisted CRISPR/Cas13a amplification for the detection of BNP via electrochemiluminescence sensing platform. Anal Chim Acta 2024; 1300:342409. [PMID: 38521567 DOI: 10.1016/j.aca.2024.342409] [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: 12/04/2023] [Revised: 01/25/2024] [Accepted: 02/23/2024] [Indexed: 03/25/2024]
Abstract
Brain natriuretic peptide (BNP) is considered to be an important biomarker of heart failure (HF) attracting attention. However, its low concentration and short half-life in blood lead to a low-sensitivity detection of BNP, which is a challenge that has to be overcome. In this work, we propose a highly specific, highly sensitive T7 RNA polymerase-assisted clustered regularly interspaced short palindromic repeats (CRISPR)/Cas13a system to detect BNP via an electrochemiluminescence (ECL) sensing platform and incorporate exonuclease III (Exo III)-hairpin and dumbbell-shaped hybridization chain reaction (HCR) technologies. In this detection scheme, the ECL sensing platform possesses low background signal and high sensitivity. Firstly, the T7 promoter-initiated T7 RNA polymerase acts as a signal amplification technique to generate large amounts of RNAs that can activate CRISPR/Cas13a activity. Secondly, CRISPR/Cas13a is able to trans-cleave the surrounding trigger strand to produce DNA1. Thirdly, DNA1 is involved in the co-amplification reaction of Exo III and hairpin DNA, which subsequently triggers a dumbbell-shaped HCR technology. Eventually, a large number of Ru (II) molecules are inserted into the interstitial space of the dumbbell-shaped HCR to generate a strong ECL signal. The CRISPR/Cas13a possesses outstanding specificity for a single base and increased sensitivity. The tightly conformed dumbbell-shaped HCR provides higher sensitivity than the traditional linear HCR amplification technique. Ultimately, the clever combination of several amplification reactions enables the limit of detection (LOD) as low as 3.2 fg/mL. It showed promise for clinical sample testing, with recovery rates ranging from 98.4% to 103% in 5% human serum samples. This detection method offered a valuable tool for early HF detection, emphasizing the synergy of amplification strategies and specificity conferred by CRISPR/Cas13a technology.
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Affiliation(s)
- Zaiyong Zhang
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
| | - Jinglong Li
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
| | - Chunlin Chen
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
| | - Yuwei Tong
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
| | - Dehui Liu
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
| | - Cuizhi Li
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
| | - Huan Lu
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China.
| | - Li Huang
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
| | - Wanling Feng
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
| | - Xiaoting Sun
- Department of Cardiology, Guangzhou Eighth People's Hospital Guangzhou Medical University, Guangzhou, 510440, PR China
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4
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Ahsan A, Wagner D, Varaljay VA, Roman V, Kelley-Loughnane N, Reuel NF. Screening putative polyester polyurethane degrading enzymes with semi-automated cell-free expression and nitrophenyl probes. Synth Biol (Oxf) 2024; 9:ysae005. [PMID: 38414826 PMCID: PMC10898825 DOI: 10.1093/synbio/ysae005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 12/26/2023] [Accepted: 02/09/2024] [Indexed: 02/29/2024] Open
Abstract
Cell-free expression (CFE) has shown recent utility in prototyping enzymes for discovery efforts. In this work, CFE is demonstrated as an effective tool to screen putative polyester polyurethane degrading enzyme sequences sourced from metagenomic analysis of biofilms prospected on aircraft and vehicles. An automated fluid handler with a controlled temperature block is used to assemble the numerous 30 µL CFE reactions to provide more consistent results over human assembly. In sum, 13 putative hydrolase enzymes from the biofilm organisms as well as a previously verified, polyester-degrading cutinase were expressed using in-house E. coli extract and minimal linear templates. The enzymes were then tested for esterase activity directly in extract using nitrophenyl conjugated substrates, showing highest sensitivity to shorter substrates (4-nitrophenyl hexanoate and 4-nNitrophenyl valerate). This screen identified 10 enzymes with statistically significant activities against these substrates; however, all were lower in measured relative activity, on a CFE volume basis, to the established cutinase control. This approach portends the use of CFE and reporter probes to rapidly prototype, screen and design for synthetic polymer degrading enzymes from environmental consortia. Graphical Abstract.
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Affiliation(s)
- Afrin Ahsan
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, USA
| | - Dominique Wagner
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, OH, USA
- UES Inc., Dayton, OH, USA
| | - Vanessa A Varaljay
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, OH, USA
| | - Victor Roman
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, OH, USA
| | - Nancy Kelley-Loughnane
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, OH, USA
| | - Nigel F Reuel
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, USA
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5
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Yue K, Chen J, Li Y, Kai L. Advancing synthetic biology through cell-free protein synthesis. Comput Struct Biotechnol J 2023; 21:2899-2908. [PMID: 37216017 PMCID: PMC10196276 DOI: 10.1016/j.csbj.2023.05.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 05/03/2023] [Accepted: 05/03/2023] [Indexed: 05/24/2023] Open
Abstract
The rapid development of synthetic biology has enabled the production of compounds with revolutionary improvements in biotechnology. DNA manipulation tools have expedited the engineering of cellular systems for this purpose. Nonetheless, the inherent constraints of cellular systems persist, imposing an upper limit on mass and energy conversion efficiencies. Cell-free protein synthesis (CFPS) has demonstrated its potential to overcome these inherent constraints and has been instrumental in the further advancement of synthetic biology. Via the removal of the cell membranes and redundant parts of cells, CFPS has provided flexibility in directly dissecting and manipulating the Central Dogma with rapid feedback. This mini-review summarizes recent achievements of the CFPS technique and its application to a wide range of synthetic biology projects, such as minimal cell assembly, metabolic engineering, and recombinant protein production for therapeutics, as well as biosensor development for in vitro diagnostics. In addition, current challenges and future perspectives in developing a generalized cell-free synthetic biology are outlined.
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Affiliation(s)
- Ke Yue
- School of Life Sciences, Jiangsu Normal University, Xuzhou 22116, China
| | - Junyu Chen
- School of Life Sciences, Jiangsu Normal University, Xuzhou 22116, China
| | - Yingqiu Li
- School of Life Sciences, Jiangsu Normal University, Xuzhou 22116, China
| | - Lei Kai
- School of Life Sciences, Jiangsu Normal University, Xuzhou 22116, China
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6
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Pourseif MM, Masoudi-Sobhanzadeh Y, Azari E, Parvizpour S, Barar J, Ansari R, Omidi Y. Self-amplifying mRNA vaccines: Mode of action, design, development and optimization. Drug Discov Today 2022; 27:103341. [PMID: 35988718 DOI: 10.1016/j.drudis.2022.103341] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Revised: 07/14/2022] [Accepted: 08/15/2022] [Indexed: 11/25/2022]
Abstract
The mRNA-based vaccines are quality-by-design (QbD) immunotherapies that provide safe, tunable, scalable, streamlined and potent treatment possibilities against different types of diseases. The self-amplifying mRNA (saRNA) vaccines, as a highly advantageous class of mRNA vaccines, are inspired by the intracellular self-multiplication nature of some positive-sense RNA viruses. Such vaccine platforms provide a relatively increased expression level of vaccine antigen(s) together with self-adjuvanticity properties. Lined with the QbD saRNA vaccines, essential optimizations improve the stability, safety, and immunogenicity of the vaccine constructs. Here, we elaborate on the concepts and mode-of-action of mRNA and saRNA vaccines, articulate the potential limitations or technical bottlenecks, and explain possible solutions or optimization methods in the process of their design and development.
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Affiliation(s)
- Mohammad M Pourseif
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yosef Masoudi-Sobhanzadeh
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Erfan Azari
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Sepideh Parvizpour
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Jaleh Barar
- Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran; Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Rais Ansari
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, Florida, USA
| | - Yadollah Omidi
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Fort Lauderdale, Florida, USA.
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7
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Rhea KA, McDonald ND, Cole SD, Noireaux V, Lux MW, Buckley PE. Variability in cell-free expression reactions can impact qualitative genetic circuit characterization. Synth Biol (Oxf) 2022; 7:ysac011. [PMID: 35966404 PMCID: PMC9365049 DOI: 10.1093/synbio/ysac011] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 06/24/2022] [Accepted: 08/01/2022] [Indexed: 09/21/2023] Open
Abstract
Cell-free expression systems provide a suite of tools that are used in applications from sensing to biomanufacturing. One of these applications is genetic circuit prototyping, where the lack of cloning is required and a high degree of control over reaction components and conditions enables rapid testing of design candidates. Many studies have shown utility in the approach for characterizing genetic regulation elements, simple genetic circuit motifs, protein variants or metabolic pathways. However, variability in cell-free expression systems is a known challenge, whether between individuals, laboratories, instruments, or batches of materials. While the issue of variability has begun to be quantified and explored, little effort has been put into understanding the implications of this variability. For genetic circuit prototyping, it is unclear when and how significantly variability in reaction activity will impact qualitative assessments of genetic components, e.g. relative activity between promoters. Here, we explore this question by assessing DNA titrations of seven genetic circuits of increasing complexity using reaction conditions that ostensibly follow the same protocol but vary by person, instrument and material batch. Although the raw activities vary widely between the conditions, by normalizing within each circuit across conditions, reasonably consistent qualitative performance emerges for the simpler circuits. For the most complex case involving expression of three proteins, we observe a departure from this qualitative consistency, offering a provisional cautionary line where normal variability may disrupt reliable reuse of prototyping results. Our results also suggest that a previously described closed loop controller circuit may help to mitigate such variability, encouraging further work to design systems that are robust to variability. Graphical Abstract.
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Affiliation(s)
- Katherine A Rhea
- US Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, MD, USA
| | - Nathan D McDonald
- US Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, MD, USA
| | - Stephanie D Cole
- US Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, MD, USA
| | - Vincent Noireaux
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA
| | - Matthew W Lux
- US Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, MD, USA
| | - Patricia E Buckley
- US Army Combat Capabilities Development Command Chemical Biological Center, Aberdeen Proving Ground, MD, USA
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8
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Beabout K, Bernhards CB, Thakur M, Turner KB, Cole SD, Walper SA, Chávez JL, Lux MW. Optimization of Heavy Metal Sensors Based on Transcription Factors and Cell-Free Expression Systems. ACS Synth Biol 2021; 10:3040-3054. [PMID: 34723503 DOI: 10.1021/acssynbio.1c00331] [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] [Indexed: 02/03/2023]
Abstract
Many bacterial mechanisms for highly specific and sensitive detection of heavy metals and other hazards have been reengineered to serve as sensors. In some cases, these sensors have been implemented in cell-free expression systems, enabling easier design optimization and deployment in low-resource settings through lyophilization. Here, we apply the advantages of cell-free expression systems to optimize sensors based on three separate bacterial response mechanisms for arsenic, cadmium, and mercury. We achieved detection limits below the World Health Organization-recommended levels for arsenic and mercury and below the short-term US Military Exposure Guideline levels for all three. The optimization of each sensor was approached differently, leading to observations useful for the development of future sensors: (1) there can be a strong dependence of specificity on the particular cell-free expression system used, (2) tuning of relative concentrations of the sensing and reporter elements improves sensitivity, and (3) sensor performance can vary significantly with linear vs plasmid DNA. In addition, we show that simply combining DNA for the three sensors into a single reaction enables detection of each target heavy metal without any further optimization. This combined approach could lead to sensors that detect a range of hazards at once, such as a panel of water contaminants or all known variants of a target virus. For low-resource settings, such "all-hazard" sensors in a cheap, easy-to-use format could have high utility.
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Affiliation(s)
- Kathryn Beabout
- UES, Inc., Dayton, Ohio 45432, United States
- Air Force Research Laboratory, 711th Human Performance Wing, Wright-Patterson Air Force Base, Dayton, Ohio 45433, United States
| | - Casey B. Bernhards
- Excet, Inc., 6225 Brandon Avenue #360, Springfield, Virginia 22150, United States
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, 8198 Blackhawk Road, Aberdeen Proving Ground, Maryland 21010, United States
| | - Meghna Thakur
- Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, D.C. 20375, United States
- College of Science, George Mason University, Fairfax, Virginia 22030, United States
| | - Kendrick B. Turner
- Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, D.C. 20375, United States
| | - Stephanie D. Cole
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, 8198 Blackhawk Road, Aberdeen Proving Ground, Maryland 21010, United States
| | - Scott A. Walper
- Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, D.C. 20375, United States
| | - Jorge L. Chávez
- Air Force Research Laboratory, 711th Human Performance Wing, Wright-Patterson Air Force Base, Dayton, Ohio 45433, United States
| | - Matthew W. Lux
- U.S. Army Combat Capabilities Development Command Chemical Biological Center, 8198 Blackhawk Road, Aberdeen Proving Ground, Maryland 21010, United States
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9
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Dudley QM, Cai YM, Kallam K, Debreyne H, Carrasco Lopez JA, Patron NJ. Biofoundry-assisted expression and characterization of plant proteins. Synth Biol (Oxf) 2021; 6:ysab029. [PMID: 34693026 PMCID: PMC8529701 DOI: 10.1093/synbio/ysab029] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 08/25/2021] [Accepted: 09/09/2021] [Indexed: 12/29/2022] Open
Abstract
Many goals in synthetic biology, including the elucidation and refactoring of biosynthetic pathways and the engineering of regulatory circuits and networks, require knowledge of protein function. In plants, the prevalence of large gene families means it can be particularly challenging to link specific functions to individual proteins. However, protein characterization has remained a technical bottleneck, often requiring significant effort to optimize expression and purification protocols. To leverage the ability of biofoundries to accelerate design-built-test-learn cycles, we present a workflow for automated DNA assembly and cell-free expression of plant proteins that accelerates optimization and enables rapid screening of enzyme activity. First, we developed a phytobrick-compatible Golden Gate DNA assembly toolbox containing plasmid acceptors for cell-free expression using Escherichia coli or wheat germ lysates as well as a set of N- and C-terminal tag parts for detection, purification and improved expression/folding. We next optimized automated assembly of miniaturized cell-free reactions using an acoustic liquid handling platform and then compared tag configurations to identify those that increase expression. We additionally developed a luciferase-based system for rapid quantification that requires a minimal 11-amino acid tag and demonstrate facile removal of tags following synthesis. Finally, we show that several functional assays can be performed with cell-free protein synthesis reactions without the need for protein purification. Together, the combination of automated assembly of DNA parts and cell-free expression reactions should significantly increase the throughput of experiments to test and understand plant protein function and enable the direct reuse of DNA parts in downstream plant engineering workflows.
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Affiliation(s)
- Quentin M Dudley
- Engineering Biology, Earlham Institute, Norwich Research Park, Norwich, Norfolk UK
| | - Yao-Min Cai
- Engineering Biology, Earlham Institute, Norwich Research Park, Norwich, Norfolk UK
| | - Kalyani Kallam
- Engineering Biology, Earlham Institute, Norwich Research Park, Norwich, Norfolk UK
| | - Hubert Debreyne
- Engineering Biology, Earlham Institute, Norwich Research Park, Norwich, Norfolk UK
| | | | - Nicola J Patron
- Engineering Biology, Earlham Institute, Norwich Research Park, Norwich, Norfolk UK
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10
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McSweeney MA, Styczynski MP. Effective Use of Linear DNA in Cell-Free Expression Systems. Front Bioeng Biotechnol 2021; 9:715328. [PMID: 34354989 PMCID: PMC8329657 DOI: 10.3389/fbioe.2021.715328] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 07/06/2021] [Indexed: 12/27/2022] Open
Abstract
Cell-free expression systems (CFEs) are cutting-edge research tools used in the investigation of biological phenomena and the engineering of novel biotechnologies. While CFEs have many benefits over in vivo protein synthesis, one particularly significant advantage is that CFEs allow for gene expression from both plasmid DNA and linear expression templates (LETs). This is an important and impactful advantage because functional LETs can be efficiently synthesized in vitro in a few hours without transformation and cloning, thus expediting genetic circuit prototyping and allowing expression of toxic genes that would be difficult to clone through standard approaches. However, native nucleases present in the crude bacterial lysate (the basis for the most affordable form of CFEs) quickly degrade LETs and limit expression yield. Motivated by the significant benefits of using LETs in lieu of plasmid templates, numerous methods to enhance their stability in lysate-based CFEs have been developed. This review describes approaches to LET stabilization used in CFEs, summarizes the advancements that have come from using LETs with these methods, and identifies future applications and development goals that are likely to be impactful to the field. Collectively, continued improvement of LET-based expression and other linear DNA tools in CFEs will help drive scientific discovery and enable a wide range of applications, from diagnostics to synthetic biology research tools.
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Affiliation(s)
- Megan A McSweeney
- Georgia Institute of Technology, School of Chemical & Biomolecular Engineering, Atlanta, GA, United States
| | - Mark P Styczynski
- Georgia Institute of Technology, School of Chemical & Biomolecular Engineering, Atlanta, GA, United States
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11
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MacDonald IC, Seamons TR, Emmons JC, Javdan SB, Deans TL. Enhanced regulation of prokaryotic gene expression by a eukaryotic transcriptional activator. Nat Commun 2021; 12:4109. [PMID: 34226549 PMCID: PMC8257575 DOI: 10.1038/s41467-021-24434-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 06/17/2021] [Indexed: 11/23/2022] Open
Abstract
Expanding the genetic toolbox for prokaryotic synthetic biology is a promising strategy for enhancing the dynamic range of gene expression and enabling new engineered applications for research and biomedicine. Here, we reverse the current trend of moving genetic parts from prokaryotes to eukaryotes and demonstrate that the activating eukaryotic transcription factor QF and its corresponding DNA-binding sequence can be moved to E. coli to introduce transcriptional activation, in addition to tight off states. We further demonstrate that the QF transcription factor can be used in genetic devices that respond to low input levels with robust and sustained output signals. Collectively, we show that eukaryotic gene regulator elements are functional in prokaryotes and establish a versatile and broadly applicable approach for constructing genetic circuits with complex functions. These genetic tools hold the potential to improve biotechnology applications for medical science and research. Expanded toolkits for prokaryotic synthetic biology can enhance the dynamic range of gene expression. Here the authors move the eukaryotic transcription factor QF into E. coli and integrate it into genetic devices.
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Affiliation(s)
- I Cody MacDonald
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Travis R Seamons
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Jonathan C Emmons
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Shwan B Javdan
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Tara L Deans
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA.
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12
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Rapid in vitro prototyping of O-methyltransferases for pathway applications in Escherichia coli. Cell Chem Biol 2021; 28:876-886.e4. [PMID: 33957079 DOI: 10.1016/j.chembiol.2021.04.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 02/20/2021] [Accepted: 04/16/2021] [Indexed: 11/22/2022]
Abstract
O-Methyltransferases are ubiquitous enzymes involved in biosynthetic pathways for secondary metabolites such as bacterial antibiotics, human catecholamine neurotransmitters, and plant phenylpropanoids. While thousands of putative O-methyltransferases are found in sequence databases, few examples are functionally characterized. From a pathway engineering perspective, however, it is crucial to know the substrate and product ranges of the respective enzymes to fully exploit their catalytic power. In this study, we developed an in vitro prototyping workflow that allowed us to screen ∼30 enzymes against five substrates in 3 days with high reproducibility. We combined in vitro transcription/translation of the genes of interest with a microliter-scale enzymatic assay in 96-well plates. The substrate conversion was indirectly measured by quantifying the consumption of the S-adenosyl-L-methionine co-factor by time-resolved fluorescence resonance energy transfer rather than time-consuming product analysis by chromatography. This workflow allowed us to rapidly prototype thus far uncharacterized O-methyltransferases for future use as biocatalysts.
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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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Moore SJ, Lai HE, Chee SM, Toh M, Coode S, Chengan K, Capel P, Corre C, de los Santos ELC, Freemont PS. A Streptomyces venezuelae Cell-Free Toolkit for Synthetic Biology. ACS Synth Biol 2021; 10:402-411. [PMID: 33497199 PMCID: PMC7901020 DOI: 10.1021/acssynbio.0c00581] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
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Prokaryotic
cell-free coupled transcription–translation
(TX-TL) systems are emerging as a powerful tool to examine natural
product biosynthetic pathways in a test tube. The key advantages of
this approach are the reduced experimental time scales and controlled
reaction conditions. To realize this potential, it is essential to
develop specialized cell-free systems in organisms enriched for biosynthetic
gene clusters. This requires strong protein production and well-characterized
synthetic biology tools. The Streptomyces genus is
a major source of natural products. To study enzymes and pathways
from Streptomyces, we originally developed a homologous Streptomyces cell-free system to provide a native protein
folding environment, a high G+C (%) tRNA pool, and an active background
metabolism. However, our initial yields were low (36 μg/mL)
and showed a high level of batch-to-batch variation. Here, we present
an updated high-yield and robust Streptomyces TX-TL
protocol, reaching up to yields of 266 μg/mL of expressed recombinant
protein. To complement this, we rapidly characterize a range of DNA
parts with different reporters, express high G+C (%) biosynthetic
genes, and demonstrate an initial proof of concept for combined transcription,
translation, and biosynthesis of Streptomyces metabolic
pathways in a single “one-pot” reaction.
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Affiliation(s)
- Simon J. Moore
- Centre for Synthetic Biology and Innovation, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
- Department Section of Structural and Synthetic Biology, Department of Infectious Disease; Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, U.K
| | - Hung-En Lai
- Centre for Synthetic Biology and Innovation, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
- Department Section of Structural and Synthetic Biology, Department of Infectious Disease; Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
| | - Soo-Mei Chee
- Department Section of Structural and Synthetic Biology, Department of Infectious Disease; Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
- The London Biofoundry, Imperial College Translation & Innovation Hub, White City Campus, 80 Wood Lane, London W12 0BZ, U.K
| | - Ming Toh
- Centre for Synthetic Biology and Innovation, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
- Department Section of Structural and Synthetic Biology, Department of Infectious Disease; Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
| | - Seth Coode
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, U.K
| | - Kameshwari Chengan
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, U.K
| | - Patrick Capel
- Warwick Integrative Synthetic Biology Centre, School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Christophe Corre
- Warwick Integrative Synthetic Biology Centre, School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Emmanuel LC de los Santos
- Warwick Integrative Synthetic Biology Centre, School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Paul S. Freemont
- Centre for Synthetic Biology and Innovation, Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
- Department Section of Structural and Synthetic Biology, Department of Infectious Disease; Imperial College London, South Kensington Campus, Exhibition Road, London, SW7 2AZ, U.K
- The London Biofoundry, Imperial College Translation & Innovation Hub, White City Campus, 80 Wood Lane, London W12 0BZ, U.K
- UK Dementia Research Institute Care Research and Technology Centre, Imperial College London, Hammersmith Campus, Du Cane Road, London, W12 0N, U.K
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15
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Benítez-Mateos AI, Zeballos N, Comino N, Moreno de Redrojo L, Randelovic T, López-Gallego F. Microcompartmentalized Cell-Free Protein Synthesis in Hydrogel μ-Channels. ACS Synth Biol 2020; 9:2971-2978. [PMID: 33170665 DOI: 10.1021/acssynbio.0c00462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The rapid demand for protein-based molecules has stimulated much research on cell-free protein synthesis (CFPS); however, there are still many challenges in terms of cost-efficiency, process intensification, and sustainability. Herein, we describe the microcompartmentalization of CFPS of superfolded green fluorescent protein (sGFP) in alginate hydrogels, which were casted into a μ-channel device. CFPS was optimized for the microcompartmentalized environment and characterized in terms of synthesis yield. To extend the scope of this technology, the use of other biocompatible materials (collagen, laponite, and agarose) was explored. In addition, the diffusion of sGFP from the hydrogel microenvironment to the bulk was demonstrated, opening a promising opportunity for concurrent synthesis and delivery of proteins. Finally, we provide an application for this system: the CFPS of enzymes. The present design of the hydrogel μ-channel device may enhance the potential application of microcompartmentalized CFPS in biosensing, bioprototyping, and therapeutic development.
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Affiliation(s)
- Ana I. Benítez-Mateos
- Heterogeneous Biocatalysis Laboratory, CICbiomaGUNE, Paseo Miramón 182. Edificio empresarial “C”, 20014 San Sebastián, Spain
- Heterogeneous Biocatalysis Laboratory, Instituto de Síntesis Química y Catálisis Homogénea (iSQCH), CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza, Spain
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Nicoll Zeballos
- Heterogeneous Biocatalysis Laboratory, CICbiomaGUNE, Paseo Miramón 182. Edificio empresarial “C”, 20014 San Sebastián, Spain
| | - Natalia Comino
- Heterogeneous Biocatalysis Laboratory, CICbiomaGUNE, Paseo Miramón 182. Edificio empresarial “C”, 20014 San Sebastián, Spain
| | - Lucía Moreno de Redrojo
- Heterogeneous Biocatalysis Laboratory, Instituto de Síntesis Química y Catálisis Homogénea (iSQCH), CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Teodora Randelovic
- Tissue MicroEnvironment (TME) Lab, Institute for Health Research Aragón (IISA), Avda. San Juan Bosco 13, 50009 Zaragoza, Spain
- Aragon Institute of Engineering Research (I3A), University of Zaragoza, Mariano Escuillor s/n, 50018 Zaragoza, Spain
| | - Fernando López-Gallego
- Heterogeneous Biocatalysis Laboratory, CICbiomaGUNE, Paseo Miramón 182. Edificio empresarial “C”, 20014 San Sebastián, Spain
- Heterogeneous Biocatalysis Laboratory, Instituto de Síntesis Química y Catálisis Homogénea (iSQCH), CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza, Spain
- IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain
- ARAID, Aragon Foundation for Science, 50009 Zaragoza, Spain
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16
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Sakono M, Hayakawa R. Repressor-Like On-Off Regulation of Protein Expression by the DNA-Binding Transcription Activator-Like Effector in T7 Promoter-Based Cell-Free Protein Synthesis. Chembiochem 2020; 22:888-893. [PMID: 33085169 DOI: 10.1002/cbic.202000591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 10/21/2020] [Indexed: 01/24/2023]
Abstract
The aim of this study was to develop a transcription activator-like effector (TALE)-based technology to regulate protein synthesis in cell-free systems. We attempted to regulate the T7 promoter system, which has no natural mechanism of expression control, and sought to arbitrarily induce protein expression through the formation and dissociation of TALE and target DNA complexes. Protein synthesis was performed in a cell-free system in the presence of TALE, which recognized and bound to a sequence upstream of the T7 promoter, and protein expression was suppressed by approximately 80 % compared to in the absence of TALE. This suggests that masking part of the promoter region strongly suppresses protein synthesis. Additionally, competitive inhibition of TALE binding to the target DNA template led to protein synthesis levels that were equivalent to the levels in the absence of TALE. Our results demonstrate that DNA recognition by TALE can regulate the expression of the T7 promoter system.
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Affiliation(s)
- Masafumi Sakono
- Department of Applied Chemistry Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama, 930-8555, Japan
| | - Ryoto Hayakawa
- Department of Applied Chemistry Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama, 930-8555, Japan
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17
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Des Soye BJ, Gerbasi VR, Thomas PM, Kelleher NL, Jewett MC. A Highly Productive, One-Pot Cell-Free Protein Synthesis Platform Based on Genomically Recoded Escherichia coli. Cell Chem Biol 2019; 26:1743-1754.e9. [PMID: 31706984 DOI: 10.1016/j.chembiol.2019.10.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 06/05/2019] [Accepted: 10/18/2019] [Indexed: 12/26/2022]
Abstract
The site-specific incorporation of non-canonical amino acids (ncAAs) into proteins via amber suppression provides access to novel protein properties, structures, and functions. Historically, poor protein expression yields resulting from release factor 1 (RF1) competition has limited this technology. To address this limitation, we develop a high-yield, one-pot cell-free platform for synthesizing proteins bearing ncAAs based on genomically recoded Escherichia coli lacking RF1. A key feature of this platform is the independence on the addition of purified T7 DNA-directed RNA polymerase (T7RNAP) to catalyze transcription. Extracts derived from our final strain demonstrate high productivity, synthesizing 2.67 ± 0.06 g/L superfolder GFP in batch mode without supplementation of purified T7RNAP. Using an optimized one-pot platform, we demonstrate multi-site incorporation of the ncAA p-acetyl-L-phenylalanine into an elastin-like polypeptide with high accuracy of incorporation and yield. Our work has implications for chemical and synthetic biology.
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Affiliation(s)
- Benjamin J Des Soye
- Interdisciplinary Biological Sciences Program, Northwestern University, Evanston, IL 60208, USA; Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208, USA; Center for Synthetic Biology, Northwestern University, Evanston, IL 60208, USA
| | - Vincent R Gerbasi
- Proteomics Center of Excellence, Northwestern University, Evanston, IL 60208, USA
| | - Paul M Thomas
- Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208, USA; Proteomics Center of Excellence, Northwestern University, Evanston, IL 60208, USA; Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
| | - Neil L Kelleher
- Interdisciplinary Biological Sciences Program, Northwestern University, Evanston, IL 60208, USA; Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208, USA; Proteomics Center of Excellence, Northwestern University, Evanston, IL 60208, USA; Department of Chemistry, Northwestern University, Evanston, IL 60208, USA; Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL 60611, USA
| | - Michael C Jewett
- Interdisciplinary Biological Sciences Program, Northwestern University, Evanston, IL 60208, USA; Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208, USA; Center for Synthetic Biology, Northwestern University, Evanston, IL 60208, USA; Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL 60611, USA; Simpson Querrey Institute, Northwestern University, Chicago, IL 60611, USA.
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