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Majekodunmi T, Britton D, Montclare JK. Engineered Proteins and Materials Utilizing Residue-Specific Noncanonical Amino Acid Incorporation. Chem Rev 2024; 124:9113-9135. [PMID: 39008623 DOI: 10.1021/acs.chemrev.3c00855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
The incorporation of noncanonical amino acids into proteins and protein-based materials has significantly expanded the repertoire of available protein structures and chemistries. Through residue-specific incorporation, protein properties can be globally modified, resulting in the creation of novel proteins and materials with diverse and tailored characteristics. In this review, we highlight recent advancements in residue-specific incorporation techniques as well as the applications of the engineered proteins and materials. Specifically, we discuss their utility in bio-orthogonal noncanonical amino acid tagging (BONCAT), fluorescent noncanonical amino acid tagging (FUNCAT), threonine-derived noncanonical amino acid tagging (THRONCAT), cross-linking, fluorination, and enzyme engineering. This review underscores the importance of noncanonical amino acid incorporation as a tool for the development of tailored protein properties to meet diverse research and industrial needs.
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Affiliation(s)
- Temiloluwa Majekodunmi
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York 11201, United States
| | - Dustin Britton
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York 11201, United States
| | - Jin Kim Montclare
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering, Brooklyn, New York 11201, United States
- Department of Biomedical Engineering, New York University Tandon School of Engineering, Brooklyn, New York 11201, United States
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York 10016, United States
- Department of Chemistry, New York University, New York, New York 10012, United States
- Department of Biomaterials, New York University College of Dentistry, New York, New York 10010, United States
- Department of Radiology, New York University Langone Health, New York, New York 10016, United States
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2
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Jann C, Giofré S, Bhattacharjee R, Lemke EA. Cracking the Code: Reprogramming the Genetic Script in Prokaryotes and Eukaryotes to Harness the Power of Noncanonical Amino Acids. Chem Rev 2024. [PMID: 39120726 DOI: 10.1021/acs.chemrev.3c00878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2024]
Abstract
Over 500 natural and synthetic amino acids have been genetically encoded in the last two decades. Incorporating these noncanonical amino acids into proteins enables many powerful applications, ranging from basic research to biotechnology, materials science, and medicine. However, major challenges remain to unleash the full potential of genetic code expansion across disciplines. Here, we provide an overview of diverse genetic code expansion methodologies and systems and their final applications in prokaryotes and eukaryotes, represented by Escherichia coli and mammalian cells as the main workhorse model systems. We highlight the power of how new technologies can be first established in simple and then transferred to more complex systems. For example, whole-genome engineering provides an excellent platform in bacteria for enabling transcript-specific genetic code expansion without off-targets in the transcriptome. In contrast, the complexity of a eukaryotic cell poses challenges that require entirely new approaches, such as striving toward establishing novel base pairs or generating orthogonally translating organelles within living cells. We connect the milestones in expanding the genetic code of living cells for encoding novel chemical functionalities to the most recent scientific discoveries, from optimizing the physicochemical properties of noncanonical amino acids to the technological advancements for their in vivo incorporation. This journey offers a glimpse into the promising developments in the years to come.
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Affiliation(s)
- Cosimo Jann
- Biocenter, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- IMB Postdoc Programme (IPPro), 55128 Mainz, Germany
| | - Sabrina Giofré
- Biocenter, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- IMB Postdoc Programme (IPPro), 55128 Mainz, Germany
| | - Rajanya Bhattacharjee
- Biocenter, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- IMB International PhD Programme (IPP), 55128 Mainz, Germany
| | - Edward A Lemke
- Biocenter, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- Institute of Molecular Biology (IMB), 55128 Mainz, Germany
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3
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Kim K, Choe D, Cho S, Palsson B, Cho BK. Reduction-to-synthesis: the dominant approach to genome-scale synthetic biology. Trends Biotechnol 2024; 42:1048-1063. [PMID: 38423803 DOI: 10.1016/j.tibtech.2024.02.008] [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: 12/14/2023] [Revised: 02/09/2024] [Accepted: 02/12/2024] [Indexed: 03/02/2024]
Abstract
Advances in systems and synthetic biology have propelled the construction of reduced bacterial genomes. Genome reduction was initially focused on exploring properties of minimal genomes, but more recently it has been deployed as an engineering strategy to enhance strain performance. This review provides the latest updates on reduced genomes, focusing on dual-track approaches of top-down reduction and bottom-up synthesis for their construction. Using cases from studies that are based on established industrial workhorse strains, we discuss the construction of a series of synthetic phenotypes that are candidates for biotechnological applications. Finally, we address the possible uses of reduced genomes for biotechnological applications and the needed future research directions that may ultimately lead to the total synthesis of rationally designed genomes.
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Affiliation(s)
- Kangsan Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea; KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Donghui Choe
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Suhyung Cho
- KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Bernhard Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA; Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Kongens, Lyngby, Denmark
| | - Byung-Kwan Cho
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea; KI for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea; Graduate School of Engineering Biology, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.
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4
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Nyerges A, Chiappino-Pepe A, Budnik B, Baas-Thomas M, Flynn R, Yan S, Ostrov N, Liu M, Wang M, Zheng Q, Hu F, Chen K, Rudolph A, Chen D, Ahn J, Spencer O, Ayalavarapu V, Tarver A, Harmon-Smith M, Hamilton M, Blaby I, Yoshikuni Y, Hajian B, Jin A, Kintses B, Szamel M, Seregi V, Shen Y, Li Z, Church GM. Synthetic genomes unveil the effects of synonymous recoding. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.16.599206. [PMID: 38915524 PMCID: PMC11195188 DOI: 10.1101/2024.06.16.599206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Engineering the genetic code of an organism provides the basis for (i) making any organism safely resistant to natural viruses and (ii) preventing genetic information flow into and out of genetically modified organisms while (iii) allowing the biosynthesis of genetically encoded unnatural polymers1-4. Achieving these three goals requires the reassignment of multiple of the 64 codons nature uses to encode proteins. However, synonymous codon replacement-recoding-is frequently lethal, and how recoding impacts fitness remains poorly explored. Here, we explore these effects using whole-genome synthesis, multiplexed directed evolution, and genome-transcriptome-translatome-proteome co-profiling on multiple recoded genomes. Using this information, we assemble a synthetic Escherichia coli genome in seven sections using only 57 codons to encode proteins. By discovering the rules responsible for the lethality of synonymous recoding and developing a data-driven multi-omics-based genome construction workflow that troubleshoots synthetic genomes, we overcome the lethal effects of 62,007 synonymous codon swaps and 11,108 additional genomic edits. We show that synonymous recoding induces transcriptional noise including new antisense RNAs, leading to drastic transcriptome and proteome perturbation. As the elimination of select codons from an organism's genetic code results in the widespread appearance of cryptic promoters, we show that synonymous codon choice may naturally evolve to minimize transcriptional noise. Our work provides the first genome-scale description of how synonymous codon changes influence organismal fitness and paves the way for the construction of functional genomes that provide genetic firewalls from natural ecosystems and safely produce biopolymers, drugs, and enzymes with an expanded chemistry.
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Affiliation(s)
- Akos Nyerges
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | | | - Bogdan Budnik
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | | | - Regan Flynn
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Shirui Yan
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- BGI Research, Shenzhen 518083, China
| | - Nili Ostrov
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Min Liu
- GenScript USA Inc., Piscataway, NJ 08854, USA
| | | | | | | | | | - Alexandra Rudolph
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Dawn Chen
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Jenny Ahn
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Owen Spencer
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | | | - Angela Tarver
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Miranda Harmon-Smith
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Matthew Hamilton
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ian Blaby
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yasuo Yoshikuni
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Behnoush Hajian
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Adeline Jin
- GenScript USA Inc., Piscataway, NJ 08854, USA
| | - Balint Kintses
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, 6726, Hungary
| | - Monika Szamel
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, 6726, Hungary
| | - Viktoria Seregi
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, 6726, Hungary
| | - Yue Shen
- BGI Research, Shenzhen 518083, China
- BGI Research, Changzhou 213299, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, BGI Research, Shenzhen 518083, China
| | - Zilong Li
- GenScript USA Inc., Piscataway, NJ 08854, USA
| | - George M. Church
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
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Chen XR, Cui YZ, Li BZ, Yuan YJ. Genome engineering on size reduction and complexity simplification: A review. J Adv Res 2024; 60:159-171. [PMID: 37442424 PMCID: PMC11156615 DOI: 10.1016/j.jare.2023.07.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/25/2023] [Accepted: 07/10/2023] [Indexed: 07/15/2023] Open
Abstract
BACKGROUND Genome simplification is an important topic in the field of life sciences that has attracted attention from its conception to the present day. It can help uncover the essential components of the genome and, in turn, shed light on the underlying operating principles of complex biological systems. This has made it a central focus of both basic and applied research in the life sciences. With the recent advancements in related technologies and our increasing knowledge of the genome, now is an opportune time to delve into this topic. AIM OF REVIEW Our review investigates the progress of genome simplification from two perspectives: genome size reduction and complexity simplification. In addition, we provide insights into the future development trends of genome simplification. KEY SCIENTIFIC CONCEPTS OF REVIEW Reducing genome size requires eliminating non-essential elements as much as possible. This process has been facilitated by advances in genome manipulation and synthesis techniques. However, we still need a better and clearer understanding of living systems to reduce genome complexity. As there is a lack of quantitative and clearly defined standards for this task, we have opted to approach the topic from various perspectives and present our findings accordingly.
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Affiliation(s)
- Xiang-Rong Chen
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - You-Zhi Cui
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Bing-Zhi Li
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China.
| | - Ying-Jin Yuan
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China; Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
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6
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Rozhoňová H, Martí-Gómez C, McCandlish DM, Payne JL. Robust genetic codes enhance protein evolvability. PLoS Biol 2024; 22:e3002594. [PMID: 38754362 PMCID: PMC11098591 DOI: 10.1371/journal.pbio.3002594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 03/19/2024] [Indexed: 05/18/2024] Open
Abstract
The standard genetic code defines the rules of translation for nearly every life form on Earth. It also determines the amino acid changes accessible via single-nucleotide mutations, thus influencing protein evolvability-the ability of mutation to bring forth adaptive variation in protein function. One of the most striking features of the standard genetic code is its robustness to mutation, yet it remains an open question whether such robustness facilitates or frustrates protein evolvability. To answer this question, we use data from massively parallel sequence-to-function assays to construct and analyze 6 empirical adaptive landscapes under hundreds of thousands of rewired genetic codes, including those of codon compression schemes relevant to protein engineering and synthetic biology. We find that robust genetic codes tend to enhance protein evolvability by rendering smooth adaptive landscapes with few peaks, which are readily accessible from throughout sequence space. However, the standard genetic code is rarely exceptional in this regard, because many alternative codes render smoother landscapes than the standard code. By constructing low-dimensional visualizations of these landscapes, which each comprise more than 16 million mRNA sequences, we show that such alternative codes radically alter the topological features of the network of high-fitness genotypes. Whereas the genetic codes that optimize evolvability depend to some extent on the detailed relationship between amino acid sequence and protein function, we also uncover general design principles for engineering nonstandard genetic codes for enhanced and diminished evolvability, which may facilitate directed protein evolution experiments and the bio-containment of synthetic organisms, respectively.
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Affiliation(s)
- Hana Rozhoňová
- Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Carlos Martí-Gómez
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - David M. McCandlish
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Joshua L. Payne
- Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
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7
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Ma Y, Su S, Fu Z, Zhou C, Qiao B, Wu Y, Yuan YJ. Convenient synthesis and delivery of a megabase-scale designer accessory chromosome empower biosynthetic capacity. Cell Res 2024; 34:309-322. [PMID: 38332200 PMCID: PMC10978979 DOI: 10.1038/s41422-024-00934-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 01/18/2024] [Indexed: 02/10/2024] Open
Abstract
Synthetic biology confers new functions to hosts by introducing exogenous genetic elements, yet rebuilding complex traits that are based on large-scale genetic information remains challenging. Here, we developed a CRISPR/Cas9-mediated haploidization method that bypasses the natural process of meiosis. Based on the programmed haploidization in yeast, we further developed an easy-to-use method designated HAnDy (Haploidization-based DNA Assembly and Delivery in yeast) that enables efficient assembly and delivery of large DNA, with no need for any fussy in vitro manipulations. Using HAnDy, a de novo designed 1.024 Mb synthetic accessory chromosome (synAC) encoding 542 exogenous genes was parallelly assembled and then directly transferred to six phylogenetically diverse yeasts. The synAC significantly promotes hosts' adaptations and increases the scope of the metabolic network, which allows the emergence of valuable compounds. Our approach should facilitate the assembly and delivery of large-scale DNA for expanding and deciphering complex biological functions.
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Affiliation(s)
- Yuan Ma
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Shuxin Su
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Zongheng Fu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Chu Zhou
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Bin Qiao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Yi Wu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China.
| | - Ying-Jin Yuan
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China.
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8
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Choe D, Olson CA, Szubin R, Yang H, Sung J, Feist AM, Palsson BO. Advancing the scale of synthetic biology via cross-species transfer of cellular functions enabled by iModulon engraftment. Nat Commun 2024; 15:2356. [PMID: 38490991 PMCID: PMC10943186 DOI: 10.1038/s41467-024-46486-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Accepted: 02/29/2024] [Indexed: 03/18/2024] Open
Abstract
Machine learning applied to large compendia of transcriptomic data has enabled the decomposition of bacterial transcriptomes to identify independently modulated sets of genes, such iModulons represent specific cellular functions. The identification of iModulons enables accurate identification of genes necessary and sufficient for cross-species transfer of cellular functions. We demonstrate cross-species transfer of: 1) the biotransformation of vanillate to protocatechuate, 2) a malonate catabolic pathway, 3) a catabolic pathway for 2,3-butanediol, and 4) an antimicrobial resistance to ampicillin found in multiple Pseudomonas species to Escherichia coli. iModulon-based engineering is a transformative strategy as it includes all genes comprising the transferred cellular function, including genes without functional annotation. Adaptive laboratory evolution was deployed to optimize the cellular function transferred, revealing mutations in the host. Combining big data analytics and laboratory evolution thus enhances the level of understanding of systems biology, and synthetic biology for strain design and development.
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Affiliation(s)
- Donghui Choe
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Connor A Olson
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Richard Szubin
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Hannah Yang
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Jaemin Sung
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Adam M Feist
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Copenhagen, Denmark
| | - Bernhard O Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA.
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Copenhagen, Denmark.
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9
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Rudolph A, Nyerges A, Chiappino-Pepe A, Landon M, Baas-Thomas M, Church G. Strategies to identify and edit improvements in synthetic genome segments episomally. Nucleic Acids Res 2023; 51:10094-10106. [PMID: 37615546 PMCID: PMC10570025 DOI: 10.1093/nar/gkad692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/30/2023] [Accepted: 08/16/2023] [Indexed: 08/25/2023] Open
Abstract
Genome engineering projects often utilize bacterial artificial chromosomes (BACs) to carry multi-kilobase DNA segments at low copy number. However, all stages of whole-genome engineering have the potential to impose mutations on the synthetic genome that can reduce or eliminate the fitness of the final strain. Here, we describe improvements to a multiplex automated genome engineering (MAGE) protocol to improve recombineering frequency and multiplexability. This protocol was applied to recoding an Escherichia coli strain to replace seven codons with synonymous alternatives genome wide. Ten 44 402-47 179 bp de novo synthesized DNA segments contained in a BAC from the recoded strain were unable to complement deletion of the corresponding 33-61 wild-type genes using a single antibiotic resistance marker. Next-generation sequencing (NGS) was used to identify 1-7 non-recoding mutations in essential genes per segment, and MAGE in turn proved a useful strategy to repair these mutations on the recoded segment contained in the BAC when both the recoded and wild-type copies of the mutated genes had to exist by necessity during the repair process. Finally, two web-based tools were used to predict the impact of a subset of non-recoding missense mutations on strain fitness using protein structure and function calls.
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Affiliation(s)
- Alexandra Rudolph
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Akos Nyerges
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Anush Chiappino-Pepe
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA 02115, USA
| | - Matthieu Landon
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | | | - George Church
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA 02115, USA
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10
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Chen L, Xin X, Zhang Y, Li S, Zhao X, Li S, Xu Z. Advances in Biosynthesis of Non-Canonical Amino Acids (ncAAs) and the Methods of ncAAs Incorporation into Proteins. Molecules 2023; 28:6745. [PMID: 37764520 PMCID: PMC10534643 DOI: 10.3390/molecules28186745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 09/18/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
The functional pool of canonical amino acids (cAAs) has been enriched through the emergence of non-canonical amino acids (ncAAs). NcAAs play a crucial role in the production of various pharmaceuticals. The biosynthesis of ncAAs has emerged as an alternative to traditional chemical synthesis due to its environmental friendliness and high efficiency. The breakthrough genetic code expansion (GCE) technique developed in recent years has allowed the incorporation of ncAAs into target proteins, giving them special functions and biological activities. The biosynthesis of ncAAs and their incorporation into target proteins within a single microbe has become an enticing application of such molecules. Based on that, in this study, we first review the biosynthesis methods for ncAAs and analyze the difficulties related to biosynthesis. We then summarize the GCE methods and analyze their advantages and disadvantages. Further, we review the application progress of ncAAs and anticipate the challenges and future development directions of ncAAs.
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Affiliation(s)
- Liang Chen
- College of Bioengineering, Beijing Polytechnic, Beijing 100176, China; (X.X.); (Y.Z.); (S.L.); (X.Z.); (S.L.); (Z.X.)
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11
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He B, Ma Y, Tian F, Zhao GR, Wu Y, Yuan YJ. YLC-assembly: large DNA assembly via yeast life cycle. Nucleic Acids Res 2023; 51:8283-8292. [PMID: 37486765 PMCID: PMC10450165 DOI: 10.1093/nar/gkad599] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 07/14/2023] [Indexed: 07/25/2023] Open
Abstract
As an enabling technique of synthetic biology, the scale of DNA assembly largely determines the scale of genetic manipulation. However, large DNA assembly technologies are generally cumbersome and inefficient. Here, we developed a YLC (yeast life cycle)-assembly method that enables in vivo iterative assembly of large DNA by nesting cell-cell transfer of assembled DNA in the cycle of yeast mating and sporulation. Using this method, we successfully assembled a hundred-kilobase (kb)-sized endogenous yeast DNA and a megabase (Mb)-sized exogenous DNA. For each round, over 104 positive colonies per 107 cells could be obtained, with an accuracy ranging from 67% to 100%. Compared with other Mb-sized DNA assembly methods, this method exhibits a higher success rate with an easy-to-operate workflow that avoid in vitro operations of large DNA. YLC-assembly lowers the technical difficulty of Mb-sized DNA assembly and could be a valuable tool for large-scale genome engineering and synthetic genomics.
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Affiliation(s)
- Bo He
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Yuan Ma
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Fangfang Tian
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Guang-Rong Zhao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Yi Wu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
| | - Ying-Jin Yuan
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China
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12
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Zhang XE, Liu C, Dai J, Yuan Y, Gao C, Feng Y, Wu B, Wei P, You C, Wang X, Si T. Enabling technology and core theory of synthetic biology. SCIENCE CHINA. LIFE SCIENCES 2023; 66:1742-1785. [PMID: 36753021 PMCID: PMC9907219 DOI: 10.1007/s11427-022-2214-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 10/04/2022] [Indexed: 02/09/2023]
Abstract
Synthetic biology provides a new paradigm for life science research ("build to learn") and opens the future journey of biotechnology ("build to use"). Here, we discuss advances of various principles and technologies in the mainstream of the enabling technology of synthetic biology, including synthesis and assembly of a genome, DNA storage, gene editing, molecular evolution and de novo design of function proteins, cell and gene circuit engineering, cell-free synthetic biology, artificial intelligence (AI)-aided synthetic biology, as well as biofoundries. We also introduce the concept of quantitative synthetic biology, which is guiding synthetic biology towards increased accuracy and predictability or the real rational design. We conclude that synthetic biology will establish its disciplinary system with the iterative development of enabling technologies and the maturity of the core theory.
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Affiliation(s)
- Xian-En Zhang
- Faculty of Synthetic Biology, Shenzhen Institute of Advanced Technology, Shenzhen, 518055, China.
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Chenli Liu
- Faculty of Synthetic Biology, Shenzhen Institute of Advanced Technology, Shenzhen, 518055, China.
- Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
| | - Junbiao Dai
- Faculty of Synthetic Biology, Shenzhen Institute of Advanced Technology, Shenzhen, 518055, China.
- Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
| | - Yingjin Yuan
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
| | - Caixia Gao
- State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Yan Feng
- State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Bian Wu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Ping Wei
- Faculty of Synthetic Biology, Shenzhen Institute of Advanced Technology, Shenzhen, 518055, China.
- Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
| | - Chun You
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
| | - Xiaowo Wang
- Ministry of Education Key Laboratory of Bioinformatics; Center for Synthetic and Systems Biology; Bioinformatics Division, Beijing National Research Center for Information Science and Technology; Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Tong Si
- Faculty of Synthetic Biology, Shenzhen Institute of Advanced Technology, Shenzhen, 518055, China.
- Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
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13
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Beattie AT, Dunkelmann DL, Chin JW. Quintuply orthogonal pyrrolysyl-tRNA synthetase/tRNA Pyl pairs. Nat Chem 2023; 15:948-959. [PMID: 37322102 PMCID: PMC7615293 DOI: 10.1038/s41557-023-01232-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 05/03/2023] [Indexed: 06/17/2023]
Abstract
Mutually orthogonal aminoacyl transfer RNA synthetase/transfer RNA pairs provide a foundation for encoding non-canonical amino acids into proteins, and encoded non-canonical polymer and macrocycle synthesis. Here we discover quintuply orthogonal pyrrolysyl-tRNA synthetase (PylRS)/pyrrolysyl-tRNA (tRNAPyl) pairs. We discover empirical sequence identity thresholds for mutual orthogonality and use these for agglomerative clustering of PylRS and tRNAPyl sequences; this defines numerous sequence clusters, spanning five classes of PylRS/tRNAPyl pairs (the existing classes +N, A and B, and newly defined classes C and S). Most of the PylRS clusters belong to classes that were unexplored for orthogonal pair generation. By testing pairs from distinct clusters and classes, and pyrrolysyl-tRNAs with unusual structures, we resolve 80% of the pairwise specificities required to make quintuply orthogonal PylRS/tRNAPyl pairs; we control the remaining specificities by engineering and directed evolution. Overall, we create 924 mutually orthogonal PylRS/tRNAPyl pairs, 1,324 triply orthogonal pairs, 128 quadruply orthogonal pairs and 8 quintuply orthogonal pairs. These advances may provide a key foundation for encoded polymer synthesis.
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Affiliation(s)
- Adam T Beattie
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Jason W Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
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14
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Zürcher JF, Kleefeldt AA, Funke LFH, Birnbaum J, Fredens J, Grazioli S, Liu KC, Spinck M, Petris G, Murat P, Rehm FBH, Sale JE, Chin JW. Continuous synthesis of E. coli genome sections and Mb-scale human DNA assembly. Nature 2023; 619:555-562. [PMID: 37380776 PMCID: PMC7614783 DOI: 10.1038/s41586-023-06268-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 05/26/2023] [Indexed: 06/30/2023]
Abstract
Whole-genome synthesis provides a powerful approach for understanding and expanding organism function1-3. To build large genomes rapidly, scalably and in parallel, we need (1) methods for assembling megabases of DNA from shorter precursors and (2) strategies for rapidly and scalably replacing the genomic DNA of organisms with synthetic DNA. Here we develop bacterial artificial chromosome (BAC) stepwise insertion synthesis (BASIS)-a method for megabase-scale assembly of DNA in Escherichia coli episomes. We used BASIS to assemble 1.1 Mb of human DNA containing numerous exons, introns, repetitive sequences, G-quadruplexes, and long and short interspersed nuclear elements (LINEs and SINEs). BASIS provides a powerful platform for building synthetic genomes for diverse organisms. We also developed continuous genome synthesis (CGS)-a method for continuously replacing sequential 100 kb stretches of the E. coli genome with synthetic DNA; CGS minimizes crossovers1,4 between the synthetic DNA and the genome such that the output for each 100 kb replacement provides, without sequencing, the input for the next 100 kb replacement. Using CGS, we synthesized a 0.5 Mb section of the E. coli genome-a key intermediate in its total synthesis1-from five episomes in 10 days. By parallelizing CGS and combining it with rapid oligonucleotide synthesis and episome assembly5,6, along with rapid methods for compiling a single genome from strains bearing distinct synthetic genome sections1,7,8, we anticipate that it will be possible to synthesize entire E. coli genomes from functional designs in less than 2 months.
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Affiliation(s)
- Jérôme F Zürcher
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Askar A Kleefeldt
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Louise F H Funke
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
- Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore
| | - Jakob Birnbaum
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Julius Fredens
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
- Synthetic Biology for Clinical and Technological Innovation, Department of Biochemistry, National University of Singapore, Singapore, Singapore
| | - Simona Grazioli
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Kim C Liu
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Martin Spinck
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Gianluca Petris
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
- Wellcome Sanger Institute, Wellcome Trust Genome Campus, Hinxton, UK
| | - Pierre Murat
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Fabian B H Rehm
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Julian E Sale
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Jason W Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
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15
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Gerecht K, Freund N, Liu W, Liu Y, Fürst MJLJ, Holliger P. The Expanded Central Dogma: Genome Resynthesis, Orthogonal Biosystems, Synthetic Genetics. Annu Rev Biophys 2023; 52:413-432. [PMID: 37159296 DOI: 10.1146/annurev-biophys-111622-091203] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Synthetic biology seeks to probe fundamental aspects of biological form and function by construction [i.e., (re)synthesis] rather than deconstruction (analysis). In this sense, biological sciences now follow the lead given by the chemical sciences. Synthesis can complement analytic studies but also allows novel approaches to answering fundamental biological questions and opens up vast opportunities for the exploitation of biological processes to provide solutions for global problems. In this review, we explore aspects of this synthesis paradigm as applied to the chemistry and function of nucleic acids in biological systems and beyond, specifically, in genome resynthesis, synthetic genetics (i.e., the expansion of the genetic alphabet, of the genetic code, and of the chemical make-up of genetic systems), and the elaboration of orthogonal biosystems and components.
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Affiliation(s)
- Karola Gerecht
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom;
| | - Niklas Freund
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom;
| | - Wei Liu
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom;
| | - Yang Liu
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom;
| | - Maximilian J L J Fürst
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom;
- Current address: Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, Netherlands
| | - Philipp Holliger
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom;
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16
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CRISPR-Cas9 mediated phage therapy as an alternative to antibiotics. ANIMAL DISEASES 2023. [DOI: 10.1186/s44149-023-00065-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
AbstractInappropriate use of antibiotics is globally creating public health hazards associated with antibiotic resistance. Bacteria often acquire antibiotic resistance by altering their genes through mutation or acquisition of plasmid-encoding resistance genes. To treat drug-resistant strains of bacteria, the recently developed CRISPR-Cas9 system might be an alternative molecular tool to conventional antibiotics. It disables antibiotic-resistance genes (plasmids) or deactivates bacterial virulence factors and sensitizes drug-resistant bacteria through site-specific cleavage of crucial domains of their genome. This molecular tool uses phages as vehicles for CRISPR-cas9 delivery into bacteria. Since phages are species-specific and natural predators of bacteria, they are capable of easily injecting their DNA to target bacteria. The CRISPR system is packaged into phagemid vectors, in such a way that the bacteria containing the antibiotic-resistance plasmid sequence or that containing specific DNA sequences were made to be targeted. Upon CRISPR delivery, Cas9 is programmed to recognize target sequences through the guide RNA thereby causing double-strand cleavage of targeted bacterial DNA or loss of drug resistance plasmid, which results in cell death. Remarkably, the safety and efficacy of this newly developed biotechnology tool and the biocontrol product need to be further refined for its usage in clinical translation.
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17
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Zhang H, Xiong Y, Xiao W, Wu Y. Investigation of Genome Biology by Synthetic Genome Engineering. Bioengineering (Basel) 2023; 10:bioengineering10020271. [PMID: 36829765 PMCID: PMC9952402 DOI: 10.3390/bioengineering10020271] [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: 01/12/2023] [Revised: 02/10/2023] [Accepted: 02/13/2023] [Indexed: 02/22/2023] Open
Abstract
Synthetic genomes were designed based on an understanding of natural genomic information, offering an opportunity to engineer and investigate biological systems on a genome-wide scale. Currently, the designer version of the M. mycoides genome and the E. coli genome, as well as most of the S. cerevisiae genome, have been synthesized, and through the cycles of design-build-test and the following engineering of synthetic genomes, many fundamental questions of genome biology have been investigated. In this review, we summarize the use of synthetic genome engineering to explore the structure and function of genomes, and highlight the unique values of synthetic genomics.
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Affiliation(s)
- Hui Zhang
- Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Yao Xiong
- Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Wenhai Xiao
- Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Yi Wu
- Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Correspondence:
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18
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Bai S, Han X, Feng D. Shoot-root signal circuit: Phytoremediation of heavy metal contaminated soil. FRONTIERS IN PLANT SCIENCE 2023; 14:1139744. [PMID: 36890896 PMCID: PMC9987563 DOI: 10.3389/fpls.2023.1139744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
High concentrations of heavy metals in the environment will cause serious harm to ecosystems and human health. It is urgent to develop effective methods to control soil heavy metal pollution. Phytoremediation has advantages and potential for soil heavy metal pollution control. However, the current hyperaccumulators have the disadvantages of poor environmental adaptability, single enrichment species and small biomass. Based on the concept of modularity, synthetic biology makes it possible to design a wide range of organisms. In this paper, a comprehensive strategy of "microbial biosensor detection - phytoremediation - heavy metal recovery" for soil heavy metal pollution control was proposed, and the required steps were modified by using synthetic biology methods. This paper summarizes the new experimental methods that promote the discovery of synthetic biological elements and the construction of circuits, and combs the methods of producing transgenic plants to facilitate the transformation of constructed synthetic biological vectors. Finally, the problems that should be paid more attention to in the remediation of soil heavy metal pollution based on synthetic biology were discussed.
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Affiliation(s)
- Shiyan Bai
- College of Biological Science and Engineering, Fuzhou University, Fujian, China
| | - Xiao Han
- College of Biological Science and Engineering, Fuzhou University, Fujian, China
| | - Dan Feng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
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19
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Development of mass allelic exchange, a technique to enable sexual genetics in Escherichia coli. Proc Natl Acad Sci U S A 2022; 119:e2105458119. [PMID: 36322728 PMCID: PMC9659338 DOI: 10.1073/pnas.2105458119] [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: 01/25/2023] Open
Abstract
Despite dramatic advances in genomics, connecting genotypes to phenotypes is still challenging. Sexual genetics combined with linkage analysis is a powerful solution to this problem but generally unavailable in bacteria. We build upon a strong negative selection system to invent mass allelic exchange (MAE), which enables hybridization of arbitrary (including pathogenic) strains of Escherichia coli. MAE reimplements the natural phenomenon of random cross-overs, enabling classical linkage analysis. We demonstrate the utility of MAE with virulence-related gain-of-function screens, discovering that transfer of a single operon from a uropathogenic strain is sufficient for enabling a commensal E. coli to form large intracellular bacterial collections within bladder epithelial cells. MAE thus enables assaying natural allelic variation in E. coli (and potentially other bacteria), complementing existing loss-of-function genomic techniques.
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20
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Zürcher JF, Robertson WE, Kappes T, Petris G, Elliott TS, Salmond GPC, Chin JW. Refactored genetic codes enable bidirectional genetic isolation. Science 2022; 378:516-523. [PMID: 36264827 PMCID: PMC7614150 DOI: 10.1126/science.add8943] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The near-universal genetic code defines the correspondence between codons in genes and amino acids in proteins. We refactored the structure of the genetic code in Escherichia coli and created orthogonal genetic codes that restrict the escape of synthetic genetic information into natural life. We developed orthogonal and mutually orthogonal horizontal gene transfer systems, which permit the transfer of genetic information between organisms that use the same genetic code but restrict the transfer of genetic information between organisms that use different genetic codes. Moreover, we showed that locking refactored codes into synthetic organisms completely blocks invasion by mobile genetic elements, including viruses, which carry their own translation factors and successfully invade organisms with canonical and compressed genetic codes.
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Affiliation(s)
- Jérôme F. Zürcher
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Tomás Kappes
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Gianluca Petris
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Thomas S. Elliott
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Jason W. Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK,Correspondence to:
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21
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Piñero-Lambea C, Garcia-Ramallo E, Miravet-Verde S, Burgos R, Scarpa M, Serrano L, Lluch-Senar M. SURE editing: combining oligo-recombineering and programmable insertion/deletion of selection markers to efficiently edit the Mycoplasma pneumoniae genome. Nucleic Acids Res 2022; 50:e127. [PMID: 36215032 PMCID: PMC9825166 DOI: 10.1093/nar/gkac836] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 08/03/2022] [Accepted: 09/28/2022] [Indexed: 01/29/2023] Open
Abstract
The development of advanced genetic tools is boosting microbial engineering which can potentially tackle wide-ranging challenges currently faced by our society. Here we present SURE editing, a multi-recombinase engineering rationale combining oligonucleotide recombineering with the selective capacity of antibiotic resistance via transient insertion of selector plasmids. We test this method in Mycoplasma pneumoniae, a bacterium with a very inefficient native recombination machinery. Using SURE editing, we can seamlessly generate, in a single step, a wide variety of genome modifications at high efficiencies, including the largest possible deletion of this genome (30 Kb) and the targeted complementation of essential genes in the deletion of a region of interest. Additional steps can be taken to remove the selector plasmid from the edited area, to obtain markerless or even scarless edits. Of note, SURE editing is compatible with different site-specific recombinases for mediating transient plasmid integration. This battery of selector plasmids can be used to select different edits, regardless of the target sequence, which significantly reduces the cloning load associated to genome engineering projects. Given the proven functionality in several microorganisms of the machinery behind the SURE editing logic, this method is likely to represent a valuable advance for the synthetic biology field.
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Affiliation(s)
| | | | - Samuel Miravet-Verde
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | - Raul Burgos
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | | | - Luis Serrano
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain,Universitat Pompeu Fabra (UPF), Barcelona 08002, Spain,ICREA, Pg. Lluís Companys 23, Barcelona 08010, Spain
| | - Maria Lluch-Senar
- Correspondence may also be addressed to Maria Lluch-Senar. Tel: +34 661963680;
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22
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Takamori S, Cicuta P, Takeuchi S, Di Michele L. DNA-assisted selective electrofusion (DASE) of Escherichia coli and giant lipid vesicles. NANOSCALE 2022; 14:14255-14267. [PMID: 36129323 PMCID: PMC9536516 DOI: 10.1039/d2nr03105a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 08/24/2022] [Indexed: 05/27/2023]
Abstract
Synthetic biology and cellular engineering require chemical and physical alterations, which are typically achieved by fusing target cells with each other or with payload-carrying vectors. On one hand, electrofusion can efficiently induce the merging of biological cells and/or synthetic analogues via the application of intense DC pulses, but it lacks selectivity and often leads to uncontrolled fusion. On the other hand, synthetic DNA-based constructs, inspired by natural fusogenic proteins, have been shown to induce a selective fusion between membranes, albeit with low efficiency. Here we introduce DNA-assisted selective electrofusion (DASE) which relies on membrane-anchored DNA constructs to bring together the objects one seeks to merge, and applying an electric impulse to trigger their fusion. The DASE process combines the efficiency of standard electrofusion and the selectivity of fusogenic nanostructures, as we demonstrate by inducing and characterizing the fusion of spheroplasts derived from Escherichia coli bacteria with cargo-carrying giant lipid vesicles.
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Affiliation(s)
- Sho Takamori
- Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK.
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan.
- Artificial Cell Membrane Systems Group, Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
| | - Pietro Cicuta
- Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK.
| | - Shoji Takeuchi
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan.
- Artificial Cell Membrane Systems Group, Kanagawa Institute of Industrial Science and Technology, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan
- Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8654, Japan
- International Research Center for Neurointelligence (IRCN), The University of Tokyo Institutes for Advanced Study (UTIAS), The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8654, Japan
| | - Lorenzo Di Michele
- Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK.
- Department of Chemistry, Imperial College London, London W12 0BZ, UK.
- fabriCELL, Imperial College London, London W12 0BZ, UK
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23
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Nierhaus T, McLaughlin SH, Bürmann F, Kureisaite-Ciziene D, Maslen SL, Skehel JM, Yu CWH, Freund SMV, Funke LFH, Chin JW, Löwe J. Bacterial divisome protein FtsA forms curved antiparallel double filaments when binding to FtsN. Nat Microbiol 2022; 7:1686-1701. [PMID: 36123441 PMCID: PMC7613929 DOI: 10.1038/s41564-022-01206-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 07/19/2022] [Indexed: 11/08/2022]
Abstract
During bacterial cell division, filaments of tubulin-like FtsZ form the Z-ring, which is the cytoplasmic scaffold for divisome assembly. In Escherichia coli, the actin homologue FtsA anchors the Z-ring to the membrane and recruits divisome components, including bitopic FtsN. FtsN regulates the periplasmic peptidoglycan synthase FtsWI. To characterize how FtsA regulates FtsN, we applied electron microscopy to show that E. coli FtsA forms antiparallel double filaments on lipid monolayers when bound to the cytoplasmic tail of FtsN. Using X-ray crystallography, we demonstrate that Vibrio maritimus FtsA crystallizes as an equivalent double filament. We identified an FtsA-FtsN interaction site in the IA-IC interdomain cleft of FtsA using X-ray crystallography and confirmed that FtsA forms double filaments in vivo by site-specific cysteine cross-linking. FtsA-FtsN double filaments reconstituted in or on liposomes prefer negative Gaussian curvature, like those of MreB, the actin-like protein of the elongasome. We propose that curved antiparallel FtsA double filaments together with treadmilling FtsZ filaments organize septal peptidoglycan synthesis in the division plane.
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Affiliation(s)
- Tim Nierhaus
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | | | | | | | - Sarah L Maslen
- MRC Laboratory of Molecular Biology, Cambridge, UK
- The Francis Crick Institute, London, UK
| | - J Mark Skehel
- MRC Laboratory of Molecular Biology, Cambridge, UK
- The Francis Crick Institute, London, UK
| | - Conny W H Yu
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | | | | | - Jason W Chin
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Jan Löwe
- MRC Laboratory of Molecular Biology, Cambridge, UK.
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24
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Gowland S, Jewett MC. Mobile Translation Systems Generate Genomically Engineered Escherichia coli Cells with Improved Growth Phenotypes. ACS Synth Biol 2022; 11:2969-2978. [PMID: 35951371 PMCID: PMC9990117 DOI: 10.1021/acssynbio.2c00099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Cellular translation is responsible for the synthesis of proteins, a highly diverse class of macromolecules that form the basis of biological function. In Escherichia coli, harnessing and engineering of the biomolecular components of translation, such as ribosomes, transfer RNAs (tRNAs), and aminoacyl-tRNA synthetases, has led to both biotechnology products and an expanded genetic code. However, the engineering potential of molecular translation is hampered by the limited capabilities for rapidly sampling the large genomic space necessary to evolve well-coordinated synthetic translation networks inside cells. To address this limitation, we developed a genome engineering method inspired by the action of mobile genetic elements termed mobilization. Mobilization utilizes the stochastic action of the recombinase flippase (FLP) to generate up to ∼400 million genomic insertions, deletions, or rearrangements at flippase recognition target sites per milliliter of culture per OD in living E. coli cells. As a model, we applied our approach to evolve faster-growing E. coli strains living exclusively off genomically expressed tethered ribosomes. In an iterative "pulse-passaging scheme," we generated genomic libraries of cells via induction of FLP recombinase (pulse) followed by passaging the population without induction of FLP to enrich the resulting population for cells with higher fitness. We observed large structural genomic diversity across these cells, with the fastest growing strains exhibiting a 71% increase in growth rate compared to the ancestral strain. We anticipate that both these strains and the mobilization method will be useful tools for synthetic biology efforts to engineer translation systems.
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Affiliation(s)
- Samuel Gowland
- 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
| | - 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.,Simpson Querrey Institute, Northwestern University, Chicago, Illinois 60611, United States
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25
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Past, Present, and Future of Genome Modification in Escherichia coli. Microorganisms 2022; 10:microorganisms10091835. [PMID: 36144436 PMCID: PMC9504249 DOI: 10.3390/microorganisms10091835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 09/05/2022] [Accepted: 09/05/2022] [Indexed: 12/04/2022] Open
Abstract
Escherichia coli K-12 is one of the most well-studied species of bacteria. This species, however, is much more difficult to modify by homologous recombination (HR) than other model microorganisms. Research on HR in E. coli has led to a better understanding of the molecular mechanisms of HR, resulting in technical improvements and rapid progress in genome research, and allowing whole-genome mutagenesis and large-scale genome modifications. Developments using λ Red (exo, bet, and gam) and CRISPR-Cas have made E. coli as amenable to genome modification as other model microorganisms, such as Saccharomyces cerevisiae and Bacillus subtilis. This review describes the history of recombination research in E. coli, as well as improvements in techniques for genome modification by HR. This review also describes the results of large-scale genome modification of E. coli using these technologies, including DNA synthesis and assembly. In addition, this article reviews recent advances in genome modification, considers future directions, and describes problems associated with the creation of cells by design.
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Liang Z, Luo Z, Zhang W, Yu K, Wang H, Geng B, Yang Q, Ni Z, Zeng C, Zheng Y, Li C, Yang S, Ma Y, Dai J. Synthetic refactor of essential genes decodes functionally constrained sequences in yeast genome. iScience 2022; 25:104982. [PMID: 36093046 PMCID: PMC9460170 DOI: 10.1016/j.isci.2022.104982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 07/14/2022] [Accepted: 08/16/2022] [Indexed: 11/28/2022] Open
Affiliation(s)
- Zhenzhen Liang
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Zhouqing Luo
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, China
- Corresponding author
| | - Weimin Zhang
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- Institute for Systems Genetics and Department of Biochemistry and Molecular Pharmacology, New York University Langone Medical Center, New York, NY 10011, USA
| | - Kang Yu
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Hui Wang
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, China
| | - Binan Geng
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China
| | - Qing Yang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China
| | - Zuoyu Ni
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Cheng Zeng
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Yihui Zheng
- Key Laboratory for Industrial Biocatalysis (Ministry of Education) and Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Chunyuan Li
- Key Laboratory for Industrial Biocatalysis (Ministry of Education) and Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shihui Yang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China
| | - Yingxin Ma
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Junbiao Dai
- CAS Key Laboratory of Quantitative Engineering Biology, Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- Key Laboratory for Industrial Biocatalysis (Ministry of Education) and Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Corresponding author
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27
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Tittle JM, Schwark DG, Biddle W, Schmitt MA, Fisk JD. Impact of queuosine modification of endogenous E. coli tRNAs on sense codon reassignment. Front Mol Biosci 2022; 9:938114. [PMID: 36120552 PMCID: PMC9471426 DOI: 10.3389/fmolb.2022.938114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
The extent to which alteration of endogenous tRNA modifications may be exploited to improve genetic code expansion efforts has not been broadly investigated. Modifications of tRNAs are strongly conserved evolutionarily, but the vast majority of E. coli tRNA modifications are not essential. We identified queuosine (Q), a non-essential, hypermodified guanosine nucleoside found in position 34 of the anticodons of four E. coli tRNAs as a modification that could potentially be utilized to improve sense codon reassignment. One suggested purpose of queuosine modification is to reduce the preference of tRNAs with guanosine (G) at position 34 of the anticodon for decoding cytosine (C) ending codons over uridine (U) ending codons. We hypothesized that introduced orthogonal translation machinery with adenine (A) at position 34 would reassign U-ending codons more effectively in queuosine-deficient E. coli. We evaluated the ability of introduced orthogonal tRNAs with AUN anticodons to reassign three of the four U-ending codons normally decoded by Q34 endogenous tRNAs: histidine CAU, asparagine AAU, and aspartic acid GAU in the presence and absence of queuosine modification. We found that sense codon reassignment efficiencies in queuosine-deficient strains are slightly improved at Asn AAU, equivalent at His CAU, and less efficient at Asp GAU codons. Utilization of orthogonal pair-directed sense codon reassignment to evaluate competition events that do not occur in the standard genetic code suggests that tRNAs with inosine (I, 6-deaminated A) at position 34 compete much more favorably against G34 tRNAs than Q34 tRNAs. Continued evaluation of sense codon reassignment following targeted alterations to endogenous tRNA modifications has the potential to shed new light on the web of interactions that combine to preserve the fidelity of the genetic code as well as identify opportunities for exploitation in systems with expanded genetic codes.
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28
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McElwain L, Phair K, Kealey C, Brady D. Current trends in biopharmaceuticals production in Escherichia coli. Biotechnol Lett 2022; 44:917-931. [PMID: 35796852 DOI: 10.1007/s10529-022-03276-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/17/2022] [Indexed: 01/07/2023]
Abstract
Since the manufacture of the first biotech product for a fledgling biopharmaceutical industry in 1982, Escherichia coli, has played an important role in the industrial production of recombinant proteins. It is now 40 years since the introduction of Humulin® for the treatment of diabetes. E. coli remains an important production host, its use as a cell factory is well established and it has become the most popular expression platform particularly for non-glycosylated therapeutic proteins. A number of significant inherent obstacles in the use of prokaryotic expression systems to produce biologics has always restricted production. These include codon usage, the absence of post-translational modifications and proteolytic processing at the cell envelope. In this review, we reflect on the contribution that this model organism has made in the production of new biotech products for human medicine. This will include new advancements in the E. coli expression system to meet the biotechnology industry requirements, such as novel engineered strains to glycosylate heterologous proteins, add disulphide bonds and express complex proteins. The biopharmaceutical market is growing rapidly, with two production systems competing for market dominance: mammalian cells and microorganisms. In the past 10 years, with increased growth of antibody-based therapies, mammalian hosts particularly CHO cells have dominated. However, with new antibody like scaffolds and mimetics emerging as future proteins of interest, E. coli has again the opportunity to be the selected as the production system of choice.
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Affiliation(s)
- L McElwain
- EnviroCORE, Department of Applied Science, South East Technological University, SETU Carlow, Kilkenny Road, Carlow, R93V960, Ireland
| | - K Phair
- EnviroCORE, Department of Applied Science, South East Technological University, SETU Carlow, Kilkenny Road, Carlow, R93V960, Ireland
| | - C Kealey
- Department of Pharmaceutical Sciences and Biotechnology, Technical University of the Shannon: Midlands Midwest, Athlone Campus, Dublin Road, Kilmacuagh, Athlone, N37 HD68, County Westmeath, Ireland
| | - D Brady
- EnviroCORE, Department of Applied Science, South East Technological University, SETU Carlow, Kilkenny Road, Carlow, R93V960, Ireland.
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29
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Venter JC, Glass JI, Hutchison CA, Vashee S. Synthetic chromosomes, genomes, viruses, and cells. Cell 2022; 185:2708-2724. [DOI: 10.1016/j.cell.2022.06.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/24/2022] [Accepted: 06/24/2022] [Indexed: 10/17/2022]
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30
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Zhang W, Brosh R, McCulloch LH, Zhu Y, Ashe H, Ellis G, Camellato BR, Kim SY, Maurano MT, Boeke JD. A conditional counterselectable Piga knockout in mouse embryonic stem cells for advanced genome writing applications. iScience 2022; 25:104438. [PMID: 35692632 PMCID: PMC9184564 DOI: 10.1016/j.isci.2022.104438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 03/18/2022] [Accepted: 05/17/2022] [Indexed: 11/16/2022] Open
Abstract
Overwriting counterselectable markers is an efficient strategy for removing wild-type DNA or replacing it with payload DNA of interest. Currently, one bottleneck of efficient genome engineering in mammals is the shortage of counterselectable (negative selection) markers that work robustly without affecting organismal developmental potential. Here, we report a conditional Piga knockout strategy that enables efficient proaerolysin-based counterselection in mouse embryonic stem cells. The conditional Piga knockout cells show similar proaerolysin resistance as full (non-conditional) Piga deletion cells, which enables the use of a PIGA transgene as a counterselectable marker for genome engineering purposes. Native Piga function is readily restored in conditional Piga knockout cells to facilitate subsequent mouse development. We also demonstrate the generality of our strategy by engineering a conditional knockout of endogenous Hprt. Taken together, our work provides a new tool for advanced mouse genome writing and mouse model establishment.
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Affiliation(s)
- Weimin Zhang
- Institute for Systems Genetics, NYU Langone Health, New York, NY 10016, USA
| | - Ran Brosh
- Institute for Systems Genetics, NYU Langone Health, New York, NY 10016, USA
| | - Laura H McCulloch
- Institute for Systems Genetics, NYU Langone Health, New York, NY 10016, USA
| | - Yinan Zhu
- Institute for Systems Genetics, NYU Langone Health, New York, NY 10016, USA
| | - Hannah Ashe
- Institute for Systems Genetics, NYU Langone Health, New York, NY 10016, USA
| | - Gwen Ellis
- Institute for Systems Genetics, NYU Langone Health, New York, NY 10016, USA
| | | | - Sang Yong Kim
- Department of Pathology, NYU Langone Health, New York, NY 10016, USA
| | - Matthew T Maurano
- Institute for Systems Genetics, NYU Langone Health, New York, NY 10016, USA.,Department of Pathology, NYU Langone Health, New York, NY 10016, USA
| | - Jef D Boeke
- Institute for Systems Genetics, NYU Langone Health, New York, NY 10016, USA.,Department of Biochemistry and Molecular Pharmacology, NYU Langone Health, New York, NY 10016, USA.,Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY 11201, USA
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31
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Teufel M, Klein CA, Mager M, Sobetzko P. A multifunctional system for genome editing and large-scale interspecies gene transfer. Nat Commun 2022; 13:3430. [PMID: 35701417 PMCID: PMC9198041 DOI: 10.1038/s41467-022-30843-1] [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: 06/15/2021] [Accepted: 05/23/2022] [Indexed: 11/09/2022] Open
Abstract
CRISPR SWAPnDROP extends the limits of genome editing to large-scale in-vivo DNA transfer between bacterial species. Its modular platform approach facilitates species specific adaptation to confer genome editing in various species. In this study, we show the implementation of the CRISPR SWAPnDROP concept for the model organism Escherichia coli, the fast growing Vibrio natriegens and the plant pathogen Dickeya dadantii. We demonstrate the excision, transfer and integration of large chromosomal regions between E. coli, V. natriegens and D. dadantii without size-limiting intermediate DNA extraction. CRISPR SWAPnDROP also provides common genome editing approaches comprising scarless, marker-free, iterative and parallel insertions and deletions. The modular character facilitates DNA library applications, and recycling of standardized parts. Its multi-color scarless co-selection system significantly improves editing efficiency and provides visual quality controls throughout the assembly and editing process.
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Affiliation(s)
- Marc Teufel
- Philipps Universität Marburg, Synthetic Microbiology Center Marburg (SYNMIKRO), Marburg, 35043, Germany
| | - Carlo A Klein
- Philipps Universität Marburg, Synthetic Microbiology Center Marburg (SYNMIKRO), Marburg, 35043, Germany
| | - Maurice Mager
- Philipps Universität Marburg, Synthetic Microbiology Center Marburg (SYNMIKRO), Marburg, 35043, Germany
| | - Patrick Sobetzko
- Philipps Universität Marburg, Synthetic Microbiology Center Marburg (SYNMIKRO), Marburg, 35043, Germany.
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32
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Fu X, Huang Y, Shen Y. Improving the Efficiency and Orthogonality of Genetic Code Expansion. BIODESIGN RESEARCH 2022; 2022:9896125. [PMID: 37850140 PMCID: PMC10521639 DOI: 10.34133/2022/9896125] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 05/20/2022] [Indexed: 10/19/2023] Open
Abstract
The site-specific incorporation of the noncanonical amino acid (ncAA) into proteins via genetic code expansion (GCE) has enabled the development of new and powerful ways to learn, regulate, and evolve biological functions in vivo. However, cellular biosynthesis of ncAA-containing proteins with high efficiency and fidelity is a formidable challenge. In this review, we summarize up-to-date progress towards improving the efficiency and orthogonality of GCE and enhancing intracellular compatibility of introduced translation machinery in the living cells by creation and optimization of orthogonal translation components, constructing genomically recoded organism (GRO), utilization of unnatural base pairs (UBP) and quadruplet codons (four-base codons), and spatial separation of orthogonal translation.
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Affiliation(s)
- Xian Fu
- BGI-Shenzhen, Shenzhen 518083, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen 518120China
| | - Yijian Huang
- BGI-Shenzhen, Shenzhen 518083, China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yue Shen
- BGI-Shenzhen, Shenzhen 518083, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen 518120China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
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33
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Ahmed W, Gupta S, Singh D, Singh R. Insight of genetic features prevalent in three Echinoderm species (Apostichopus japonicus, Heliocedaris erythrogramma and Asterias rubens) and their evolutionary association using comparative codon pattern analysis. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2022.101589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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34
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Kimoto M, Hirao I. Genetic Code Engineering by Natural and Unnatural Base Pair Systems for the Site-Specific Incorporation of Non-Standard Amino Acids Into Proteins. Front Mol Biosci 2022; 9:851646. [PMID: 35685243 PMCID: PMC9171071 DOI: 10.3389/fmolb.2022.851646] [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: 01/10/2022] [Accepted: 04/25/2022] [Indexed: 12/21/2022] Open
Abstract
Amino acid sequences of proteins are encoded in nucleic acids composed of four letters, A, G, C, and T(U). However, this four-letter alphabet coding system limits further functionalities of proteins by the twenty letters of amino acids. If we expand the genetic code or develop alternative codes, we could create novel biological systems and biotechnologies by the site-specific incorporation of non-standard amino acids (or unnatural amino acids, unAAs) into proteins. To this end, new codons and their complementary anticodons are required for unAAs. In this review, we introduce the current status of methods to incorporate new amino acids into proteins by in vitro and in vivo translation systems, by focusing on the creation of new codon-anticodon interactions, including unnatural base pair systems for genetic alphabet expansion.
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Affiliation(s)
| | - Ichiro Hirao
- *Correspondence: Michiko Kimoto, ; Ichiro Hirao,
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35
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Xi Z, Davis L, Baxter K, Tynan A, Goutou A, Greiss S. Using a quadruplet codon to expand the genetic code of an animal. Nucleic Acids Res 2022; 50:4801-4812. [PMID: 34882769 PMCID: PMC9122531 DOI: 10.1093/nar/gkab1168] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/06/2021] [Accepted: 11/11/2021] [Indexed: 11/13/2022] Open
Abstract
Genetic code expansion in multicellular organisms is currently limited to the use of repurposed amber stop codons. Here, we introduce a system for the use of quadruplet codons to direct incorporation of non-canonical amino acids in vivo in an animal, the nematode worm Caenorhabditis elegans. We develop hybrid pyrrolysyl tRNA variants to incorporate non-canonical amino acids in response to the quadruplet codon UAGA. We demonstrate the efficiency of the quadruplet decoding system by incorporating photocaged amino acids into two proteins widely used as genetic tools. We use photocaged lysine to express photocaged Cre recombinase for the optical control of gene expression and photocaged cysteine to express photo-activatable caspase for light inducible cell ablation. Our approach will facilitate the routine adoption of quadruplet decoding for genetic code expansion in eukaryotic cells and multicellular organisms.
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Affiliation(s)
- Zhiyan Xi
- Centre for Discovery Brain Sciences, University of Edinburgh, UK
| | - Lloyd Davis
- Centre for Discovery Brain Sciences, University of Edinburgh, UK
| | - Kieran Baxter
- Centre for Discovery Brain Sciences, University of Edinburgh, UK
| | - Ailish Tynan
- Centre for Discovery Brain Sciences, University of Edinburgh, UK
| | - Angeliki Goutou
- Centre for Discovery Brain Sciences, University of Edinburgh, UK
| | - Sebastian Greiss
- Centre for Discovery Brain Sciences, University of Edinburgh, UK
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36
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Exogenous artificial DNA forms chromatin structure with active transcription in yeast. SCIENCE CHINA. LIFE SCIENCES 2022; 65:851-860. [PMID: 34970711 DOI: 10.1007/s11427-021-2044-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 12/10/2021] [Indexed: 12/25/2022]
Abstract
Yeast artificial chromosomes (YACs) are important tools for sequencing, gene cloning, and transferring large quantities of genetic information. However, the structure and activity of YAC chromatin, as well as the unintended impacts of introducing foreign DNA sequences on DNA-associated biochemical events, have not been widely explored. Here, we showed that abundant genetic elements like TATA box and transcription factor-binding motifs occurred unintentionally in a previously reported data-carrying chromosome (dChr). In addition, we used state-of-the-art sequencing technologies to comprehensively profile the genetic, epigenetic, transcriptional, and proteomic characteristics of the exogenous dChr. We found that the data-carrying DNA formed active chromatin with high chromatin accessibility and H3K4 tri-methylation levels. The dChr also displayed highly pervasive transcriptional ability and transcribed hundreds of noncoding RNAs. The results demonstrated that exogenous artificial chromosomes formed chromatin structures and did not remain as naked or loose plasmids. A better understanding of the YAC chromatin nature will improve our ability to design better data-storage chromosomes.
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37
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Ye Y, Zhong M, Zhang Z, Chen T, Shen Y, Lin Z, Wang Y. Genomic Iterative Replacements of Large Synthetic DNA Fragments in Corynebacterium glutamicum. ACS Synth Biol 2022; 11:1588-1599. [PMID: 35290032 DOI: 10.1021/acssynbio.1c00644] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Synthetic genomics will advance our understanding of life and allow us to rebuild the genomes of industrial microorganisms for enhancing performances. Corynebacterium glutamicum, a Gram-positive bacterium, is an important industrial workhorse. However, its genome synthesis is impeded by the low efficiencies in DNA delivery and in genomic recombination/replacement. In the present study, we describe a genomic iterative replacement system based on RecET recombination for C. glutamicum, involving the successive integration of up to 10 kb DNA fragments obtained in vitro, and the transformants are selected by the alternative use of kanR and speR selectable markers. As a proof of concept, we systematically redesigned and replaced a 54.3 kb wild-type sequence of C. glutamicumATCC13032 with its 55.1 kb synthetic counterpart with several novel features, including decoupled genes, the standard PCRTags, and 20 loxPsym sites, which was for the first time incorporated into a bacterial genome. The resulting strain semi-synCG-A1 had a phenotype and fitness similar to the wild-type strain under various stress conditions. The stability of the synthetic genome region faithfully maintained over 100 generations of nonselective growth. Genomic deletions, inversions, and translocations occurred in the synthetic genome region upon induction of synthetic chromosome rearrangement and modification by loxP-mediated evolution (SCRaMbLE), revealing potential genetic flexibility for C. glutamicum. This strategy can be used for the synthesis of a larger region of the genome and facilitate the endeavors for metabolic engineering and synthetic biology of C. glutamicum.
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Affiliation(s)
- Yanrui Ye
- School of Biology and Biological Engineering, South China University of Technology, 382 East Outer Loop Road, University Park, Guangzhou 510006, China
| | - Minmin Zhong
- School of Biology and Biological Engineering, South China University of Technology, 382 East Outer Loop Road, University Park, Guangzhou 510006, China
| | - Zhanhua Zhang
- School of Biology and Biological Engineering, South China University of Technology, 382 East Outer Loop Road, University Park, Guangzhou 510006, China
| | - Tai Chen
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Yue Shen
- BGI-Shenzhen, Shenzhen 518083, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen 518120, China
| | - Zhanglin Lin
- School of Biology and Biological Engineering, South China University of Technology, 382 East Outer Loop Road, University Park, Guangzhou 510006, China
| | - Yun Wang
- BGI-Shenzhen, Shenzhen 518083, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, BGI-Shenzhen, Shenzhen 518120, China
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38
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Huang C, Wang C, Luo Y. Research progress of pathway and genome evolution in microbes. Synth Syst Biotechnol 2022; 7:648-656. [PMID: 35224232 PMCID: PMC8857405 DOI: 10.1016/j.synbio.2022.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/23/2021] [Accepted: 01/06/2022] [Indexed: 12/16/2022] Open
Abstract
Microbes can produce valuable natural products widely applied in medicine, food and other important fields. Nevertheless, it is usually challenging to achieve ideal industrial yields due to low production rate and poor toxicity tolerance. Evolution is a constant mutation and adaptation process used to improve strain performance. Generally speaking, the synthesis of natural products in microbes is often intricate, involving multiple enzymes or multiple pathways. Individual evolution of a certain enzyme often fails to achieve the desired results, and may lead to new rate-limiting nodes that affect the growth of microbes. Therefore, it is inevitable to evolve the biosynthetic pathways or the whole genome. Here, we reviewed the pathway-level evolution including multi-enzyme evolution, regulatory elements engineering, and computer-aided engineering, as well as the genome-level evolution based on several tools, such as genome shuffling and CRISPR/Cas systems. Finally, we also discussed the major challenges faced by in vivo evolution strategies and proposed some potential solutions.
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Affiliation(s)
- Chaoqun Huang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Chang Wang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Yunzi Luo
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
- Georgia Tech Shenzhen Institute, Tianjin University, Tangxing Road 133, Nanshan District, Shenzhen, 518071, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin, 300072, China
- Corresponding author. Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
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39
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Biddle W, Schwark DG, Schmitt MA, Fisk JD. Directed Evolution Pipeline for the Improvement of Orthogonal Translation Machinery for Genetic Code Expansion at Sense Codons. Front Chem 2022; 10:815788. [PMID: 35252113 PMCID: PMC8891652 DOI: 10.3389/fchem.2022.815788] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/24/2022] [Indexed: 12/30/2022] Open
Abstract
The expansion of the genetic code beyond a single type of noncanonical amino acid (ncAA) is hindered by inefficient machinery for reassigning the meaning of sense codons. A major obstacle to using directed evolution to improve the efficiency of sense codon reassignment is that fractional sense codon reassignments lead to heterogeneous mixtures of full-length proteins with either a ncAA or a natural amino acid incorporated in response to the targeted codon. In stop codon suppression systems, missed incorporations lead to truncated proteins; improvements in activity may be inferred from increased protein yields or the production of downstream reporters. In sense codon reassignment, the heterogeneous proteins produced greatly complicate the development of screens for variants of the orthogonal machinery with improved activity. We describe the use of a previously-reported fluorescence-based screen for sense codon reassignment as the first step in a directed evolution workflow to improve the incorporation of a ncAA in response to the Arg AGG sense codon. We first screened a library with diversity introduced into both the orthogonal Methanocaldococcus jannaschii tyrosyl tRNA anticodon loop and the cognate aminoacyl tRNA synthetase (aaRS) anticodon binding domain for variants that improved incorporation of tyrosine in response to the AGG codon. The most efficient variants produced fluorescent proteins at levels indistinguishable from the E. coli translation machinery decoding tyrosine codons. Mutations to the M. jannaschii aaRS that were found to improve tyrosine incorporation were transplanted onto a M. jannaschii aaRS evolved for the incorporation of para-azidophenylalanine. Improved ncAA incorporation was evident using fluorescence- and mass-based reporters. The described workflow is generalizable and should enable the rapid tailoring of orthogonal machinery capable of activating diverse ncAAs to any sense codon target. We evaluated the selection based improvements of the orthogonal pair in a host genomically engineered for reduced target codon competition. Using this particular system for evaluation of arginine AGG codon reassignment, however, E. coli strains with genomes engineered to remove competing tRNAs did not outperform a standard laboratory E. coli strain in sense codon reassignment.
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40
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Bürmann F, Funke LFH, Chin JW, Löwe J. Cryo-EM structure of MukBEF reveals DNA loop entrapment at chromosomal unloading sites. Mol Cell 2021; 81:4891-4906.e8. [PMID: 34739874 PMCID: PMC8669397 DOI: 10.1016/j.molcel.2021.10.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/31/2021] [Accepted: 10/12/2021] [Indexed: 11/25/2022]
Abstract
The ring-like structural maintenance of chromosomes (SMC) complex MukBEF folds the genome of Escherichia coli and related bacteria into large loops, presumably by active DNA loop extrusion. MukBEF activity within the replication terminus macrodomain is suppressed by the sequence-specific unloader MatP. Here, we present the complete atomic structure of MukBEF in complex with MatP and DNA as determined by electron cryomicroscopy (cryo-EM). The complex binds two distinct DNA double helices corresponding to the arms of a plectonemic loop. MatP-bound DNA threads through the MukBEF ring, while the second DNA is clamped by the kleisin MukF, MukE, and the MukB ATPase heads. Combinatorial cysteine cross-linking confirms this topology of DNA loop entrapment in vivo. Our findings illuminate how a class of near-ubiquitous DNA organizers with important roles in genome maintenance interacts with the bacterial chromosome.
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Affiliation(s)
- Frank Bürmann
- MRC Laboratory of Molecular Biology, Structural Studies Division, Cambridge Biomedical Campus, Cambridge, UK.
| | - Louise F H Funke
- MRC Laboratory of Molecular Biology, Protein and Nucleic Acid Chemistry Division, Cambridge Biomedical Campus, Cambridge, UK
| | - Jason W Chin
- MRC Laboratory of Molecular Biology, Protein and Nucleic Acid Chemistry Division, Cambridge Biomedical Campus, Cambridge, UK
| | - Jan Löwe
- MRC Laboratory of Molecular Biology, Structural Studies Division, Cambridge Biomedical Campus, Cambridge, UK.
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41
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Yi H, Zhang J, Ke F, Guo X, Yang J, Xie P, Liu L, Wang Q, Gao X. Comparative Analyses of the Transcriptome and Proteome of Escherichia coli C321.△A and Further Improving Its Noncanonical Amino Acids Containing Protein Expression Ability by Integration of T7 RNA Polymerase. Front Microbiol 2021; 12:744284. [PMID: 34659179 PMCID: PMC8511705 DOI: 10.3389/fmicb.2021.744284] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 08/30/2021] [Indexed: 01/09/2023] Open
Abstract
Incorporation of noncanonical amino acids (ncAAs) into proteins has been proven to be a powerful tool to manipulate protein structure and function, and to investigate many biological processes. Improving the yields of ncAA-containing proteins is of great significance in industrial-scale applications. Escherichia coli C321.ΔA was generated by the replacement of all known amber codons and the deletion of RF1 in the genome and has been proven to be an ideal host for ncAA-containing protein expression using genetic code expansion. In this study, we investigated the transcriptome and proteome profiles of this first codon reassignment strain and found that some functions and metabolic pathways were differentially expressed when compared with those of its parent strain. Genes involved in carbohydrate and energy metabolism were remarkably downregulated. Our results may provide important clues about the growth defects in E. coli C321.ΔA. Furthermore, we improved the yields of ncAA-containing proteins in E. coli C321.ΔA by integrating the T7 RNA polymerase system.
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Affiliation(s)
- Huawei Yi
- Clinical Laboratory, The First Affiliated Hospital of Yangtze University, Jingzhou, China
| | - Jing Zhang
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Famin Ke
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Xiurong Guo
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Jian Yang
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Peijuan Xie
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Li Liu
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Qin Wang
- School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Xiaowei Gao
- School of Pharmacy, Southwest Medical University, Luzhou, China.,Department of Chemistry, Zhejiang University, Hangzhou, China
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42
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Asin-Garcia E, Martin-Pascual M, Garcia-Morales L, van Kranenburg R, Martins dos Santos VAP. ReScribe: An Unrestrained Tool Combining Multiplex Recombineering and Minimal-PAM ScCas9 for Genome Recoding Pseudomonas putida. ACS Synth Biol 2021; 10:2672-2688. [PMID: 34547891 PMCID: PMC8524654 DOI: 10.1021/acssynbio.1c00297] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Indexed: 12/11/2022]
Abstract
Genome recoding enables incorporating new functions into the DNA of microorganisms. By reassigning codons to noncanonical amino acids, the generation of new-to-nature proteins offers countless opportunities for bioproduction and biocontainment in industrial chassis. A key bottleneck in genome recoding efforts, however, is the low efficiency of recombineering, which hinders large-scale applications at acceptable speed and cost. To relieve this bottleneck, we developed ReScribe, a highly optimized recombineering tool enhanced by CRISPR-Cas9-mediated counterselection built upon the minimal PAM 5'-NNG-3' of the Streptococcus canis Cas9 (ScCas9). As a proof of concept, we used ReScribe to generate a minimally recoded strain of the industrial chassis Pseudomonas putida by replacing TAG stop codons (functioning as PAMs) of essential metabolic genes with the synonymous TAA. We showed that ReScribe enables nearly 100% engineering efficiency of multiple loci in P. putida, opening promising avenues for genome editing and applications thereof in this bacterium and beyond.
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Affiliation(s)
- Enrique Asin-Garcia
- Laboratory
of Systems and Synthetic Biology, Wageningen
University & Research, Wageningen 6708 WE, The Netherlands
| | - Maria Martin-Pascual
- Laboratory
of Systems and Synthetic Biology, Wageningen
University & Research, Wageningen 6708 WE, The Netherlands
| | - Luis Garcia-Morales
- Laboratory
of Systems and Synthetic Biology, Wageningen
University & Research, Wageningen 6708 WE, The Netherlands
| | - Richard van Kranenburg
- Corbion, Gorinchem 4206 AC, The Netherlands
- Laboratory
of Microbiology, Wageningen University &
Research, Wageningen 6708 WE, The Netherlands
| | - Vitor A. P. Martins dos Santos
- Laboratory
of Systems and Synthetic Biology, Wageningen
University & Research, Wageningen 6708 WE, The Netherlands
- LifeGlimmer
GmbH, Berlin 12163, Germany
- Bioprocess
Engineering Group, Wageningen University
& Research, Wageningen 6700 AA, The Netherlands
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43
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Reinkemeier CD, Lemke EA. Dual film-like organelles enable spatial separation of orthogonal eukaryotic translation. Cell 2021; 184:4886-4903.e21. [PMID: 34433013 PMCID: PMC8480389 DOI: 10.1016/j.cell.2021.08.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 05/03/2021] [Accepted: 08/02/2021] [Indexed: 11/18/2022]
Abstract
Engineering new functionality into living eukaryotic systems by enzyme evolution or de novo protein design is a formidable challenge. Cells do not rely exclusively on DNA-based evolution to generate new functionality but often utilize membrane encapsulation or formation of membraneless organelles to separate distinct molecular processes that execute complex operations. Applying this principle and the concept of two-dimensional phase separation, we develop film-like synthetic organelles that support protein translation on the surfaces of various cellular membranes. These sub-resolution synthetic films provide a path to make functionally distinct enzymes within the same cell. We use these film-like organelles to equip eukaryotic cells with dual orthogonal expanded genetic codes that enable the specific reprogramming of distinct translational machineries with single-residue precision. The ability to spatially tune the output of translation within tens of nanometers is not only important for synthetic biology but has implications for understanding the function of membrane-associated protein condensation in cells. 2D phase separation was utilized to design orthogonal enzymes Film-like organelles maintained distinct suppressor tRNA microenvironments Dual film-like synthetic organelles enabled orthogonal translation in eukaryotes Cells were equipped with two expanded genetic codes in addition to the canonical one
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Affiliation(s)
- Christopher D Reinkemeier
- Biocentre, Departments of Biology and Chemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; Institute of Molecular Biology gGmbH, Ackermannweg 4, 55128 Mainz, Germany; Structural and Computational Biology Unit and Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Edward A Lemke
- Biocentre, Departments of Biology and Chemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; Institute of Molecular Biology gGmbH, Ackermannweg 4, 55128 Mainz, Germany; Structural and Computational Biology Unit and Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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44
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Deng A, Sun Z, Wang T, Cui D, Li L, Liu S, Huang F, Wen T. Simultaneous Multiplex Genome Engineering via Accelerated Natural Transformation in Bacillus subtilis. Front Microbiol 2021; 12:714449. [PMID: 34484154 PMCID: PMC8416114 DOI: 10.3389/fmicb.2021.714449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/23/2021] [Indexed: 11/13/2022] Open
Abstract
Multiplex engineering at the scale of whole genomes has become increasingly important for synthetic biology and biotechnology applications. Although several methods have been reported for engineering microbe genomes, their use is limited by their complex procedures using multi-cycle transformations. Natural transformation, involving in species evolution by horizontal gene transfer in many organisms, indicates its potential as a genetic tool. Here, we aimed to develop simultaneous multiplex genome engineering (SMGE) for the simple, rapid, and efficient design of bacterial genomes via one-step of natural transformation in Bacillus subtilis. The transformed DNA, competency factors, and recombinases were adapted to improved co-editing frequencies above 27-fold. Single to octuplet variants with genetic diversity were simultaneously generated using all-in-one vectors harboring multi-gene cassettes. To demonstrate its potential application, the tyrosine biosynthesis pathway was further optimized for producing commercially important resveratrol by high-throughput screening of variant pool in B. subtilis. SMGE represents an accelerated evolution platform that generates diverse multiplex mutations for large-scale genetic engineering and synthetic biology in B. subtilis.
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Affiliation(s)
- Aihua Deng
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Zhaopeng Sun
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Tiantian Wang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Di Cui
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Lai Li
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Shuwen Liu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,China Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing, China
| | - Fei Huang
- Zenbio Biotech Co., Ltd., Chengdu, China
| | - Tingyi Wen
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,China Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
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45
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Dunkelmann DL, Oehm SB, Beattie AT, Chin JW. A 68-codon genetic code to incorporate four distinct non-canonical amino acids enabled by automated orthogonal mRNA design. Nat Chem 2021; 13:1110-1117. [PMID: 34426682 DOI: 10.1038/s41557-021-00764-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/30/2021] [Indexed: 12/15/2022]
Abstract
Orthogonal (O) ribosome-mediated translation of O-mRNAs enables the incorporation of up to three distinct non-canonical amino acids (ncAAs) into proteins in Escherichia coli (E. coli). However, the general and efficient incorporation of multiple distinct ncAAs by O-ribosomes requires scalable strategies for both creating efficiently and specifically translated O-mRNAs, and the compact expression of multiple O-aminoacyl-tRNA synthetase (O-aaRS)/O-tRNA pairs. We automate the discovery of O-mRNAs that lead to up to 40 times more protein, and are up to 50-fold more orthogonal, than previous O-mRNAs; protein yields from our O-mRNAs match or exceed those from wild-type mRNAs. These advances enable a 33-fold increase in yield for incorporating three distinct ncAAs. We automate the creation of operons for O-tRNA genes, and develop operons for O-aaRS genes. Combining our advances creates a 68-codon, 24-amino-acid genetic code to efficiently incorporate four distinct ncAAs into a single protein in response to four distinct quadruplet codons.
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Affiliation(s)
| | - Sebastian B Oehm
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Adam T Beattie
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Jason W Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
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46
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Robertson WE, Funke LFH, de la Torre D, Fredens J, Elliott TS, Spinck M, Christova Y, Cervettini D, Böge FL, Liu KC, Buse S, Maslen S, Salmond GPC, Chin JW. Sense codon reassignment enables viral resistance and encoded polymer synthesis. Science 2021; 372:1057-1062. [PMID: 34083482 DOI: 10.1126/science.abg3029] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/08/2021] [Indexed: 12/13/2022]
Abstract
It is widely hypothesized that removing cellular transfer RNAs (tRNAs)-making their cognate codons unreadable-might create a genetic firewall to viral infection and enable sense codon reassignment. However, it has been impossible to test these hypotheses. In this work, following synonymous codon compression and laboratory evolution in Escherichia coli, we deleted the tRNAs and release factor 1, which normally decode two sense codons and a stop codon; the resulting cells could not read the canonical genetic code and were completely resistant to a cocktail of viruses. We reassigned these codons to enable the efficient synthesis of proteins containing three distinct noncanonical amino acids. Notably, we demonstrate the facile reprogramming of our cells for the encoded translation of diverse noncanonical heteropolymers and macrocycles.
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Affiliation(s)
| | - Louise F H Funke
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Julius Fredens
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Thomas S Elliott
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Martin Spinck
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Yonka Christova
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Franz L Böge
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Kim C Liu
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Salvador Buse
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Sarah Maslen
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Jason W Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
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47
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Abstract
DNA synthesis technology has progressed to the point that it is now practical to synthesize entire genomes. Quite a variety of methods have been developed, first to synthesize single genes but ultimately to massively edit or write from scratch entire genomes. Synthetic genomes can essentially be clones of native sequences, but this approach does not teach us much new biology. The ability to endow genomes with novel properties offers special promise for addressing questions not easily approachable with conventional gene-at-a-time methods. These include questions about evolution and about how genomes are fundamentally wired informationally, metabolically, and genetically. The techniques and technologies relating to how to design, build, and deliver big DNA at the genome scale are reviewed here. A fuller understanding of these principles may someday lead to the ability to truly design genomes from scratch.
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Affiliation(s)
- Weimin Zhang
- Institute for Systems Genetics and Department of Biochemistry and Molecular Pharmacology, New York University Langone Health, New York, NY 10016, USA; , ,
| | - Leslie A Mitchell
- Institute for Systems Genetics and Department of Biochemistry and Molecular Pharmacology, New York University Langone Health, New York, NY 10016, USA; , ,
| | - Joel S Bader
- Department of Biomedical Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA;
| | - Jef D Boeke
- Institute for Systems Genetics and Department of Biochemistry and Molecular Pharmacology, New York University Langone Health, New York, NY 10016, USA; , , .,Department of Biomedical Engineering, New York University Tandon School of Engineering, New York, NY 11201, USA
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48
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van Kooten MJFM, Scheidegger CA, Christen M, Christen B. The transcriptional landscape of a rewritten bacterial genome reveals control elements and genome design principles. Nat Commun 2021; 12:3053. [PMID: 34031412 PMCID: PMC8144410 DOI: 10.1038/s41467-021-23362-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 04/20/2021] [Indexed: 02/04/2023] Open
Abstract
Sequence rewriting enables low-cost genome synthesis and the design of biological systems with orthogonal genetic codes. The error-free, robust rewriting of nucleotide sequences can be achieved with a complete annotation of gene regulatory elements. Here, we compare transcription in Caulobacter crescentus to transcription from plasmid-borne segments of the synthesized genome of C. ethensis 2.0. This rewritten derivative contains an extensive amount of supposedly neutral mutations, including 123'562 synonymous codon changes. The transcriptional landscape refines 60 promoter annotations, exposes 18 termination elements and links extensive transcription throughout the synthesized genome to the unintentional introduction of sigma factor binding motifs. We reveal translational regulation for 20 CDS and uncover an essential translational regulatory element for the expression of ribosomal protein RplS. The annotation of gene regulatory elements allowed us to formulate design principles that improve design schemes for synthesized DNA, en route to a bright future of iteration-free programming of biological systems.
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Affiliation(s)
- Mariëlle J F M van Kooten
- Institute of Molecular Systems Biology, Department of Biology, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland.
| | - Clio A Scheidegger
- Institute of Molecular Systems Biology, Department of Biology, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
| | - Matthias Christen
- Institute of Molecular Systems Biology, Department of Biology, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
| | - Beat Christen
- Institute of Molecular Systems Biology, Department of Biology, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland.
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49
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Yoneji T, Fujita H, Mukai T, Su'etsugu M. Grand scale genome manipulation via chromosome swapping in Escherichia coli programmed by three one megabase chromosomes. Nucleic Acids Res 2021; 49:8407-8418. [PMID: 33907814 PMCID: PMC8421210 DOI: 10.1093/nar/gkab298] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/06/2021] [Accepted: 04/10/2021] [Indexed: 11/30/2022] Open
Abstract
In bacterial synthetic biology, whole genome transplantation has been achieved only in mycoplasmas that contain a small genome and are competent for foreign genome uptake. In this study, we developed Escherichia coli strains programmed by three 1-megabase (Mb) chromosomes by splitting the 3-Mb chromosome of a genome-reduced strain. The first split-chromosome retains the original replication origin (oriC) and partitioning (par) system. The second one has an oriC and the par locus from the F plasmid, while the third one has the ori and par locus of the Vibrio tubiashii secondary chromosome. The tripartite-genome cells maintained the rod-shaped form and grew only twice as slowly as their parent, allowing their further genetic engineering. A proportion of these 1-Mb chromosomes were purified as covalently closed supercoiled molecules with a conventional alkaline lysis method and anion exchange columns. Furthermore, the second and third chromosomes could be individually electroporated into competent cells. In contrast, the first split-chromosome was not able to coexist with another chromosome carrying the same origin region. However, it was exchangeable via conjugation between tripartite-genome strains by using different selection markers. We believe that this E. coli-based technology has the potential to greatly accelerate synthetic biology and synthetic genomics.
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Affiliation(s)
- Tatsuya Yoneji
- Department of Life Science, College of Science, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan
| | - Hironobu Fujita
- Department of Life Science, College of Science, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan
| | - Takahito Mukai
- Department of Life Science, College of Science, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan
| | - Masayuki Su'etsugu
- Department of Life Science, College of Science, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan
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50
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Engineering of the Small Noncoding RNA (sRNA) DsrA Together with the sRNA Chaperone Hfq Enhances the Acid Tolerance of Escherichia coli. Appl Environ Microbiol 2021; 87:AEM.02923-20. [PMID: 33674434 DOI: 10.1128/aem.02923-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/21/2021] [Indexed: 11/20/2022] Open
Abstract
Acid tolerance of microorganisms is a desirable phenotype for many industrial fermentation applications. In Escherichia coli, the stress response sigma factor RpoS is a promising target for engineering acid-tolerant phenotypes. However, the simple overexpression of RpoS alone is insufficient to confer these phenotypes. In this study, we show that the simultaneous overexpression of the noncoding small RNA (sRNA) DsrA and the sRNA chaperone Hfq, which act as RpoS activators, significantly increased acid tolerance in terms of cell growth under modest acidic pH, as well as cell survival upon extreme acid shock. Directed evolution of the DsrA-Hfq module further improved the acid tolerance, with the best mutants showing a 51 to 72% increase in growth performance at pH 4.5 compared with the starting strain, MG1655. Further analyses found that the improved acid tolerance of these DsrA-Hfq strains coincided with activation of genes associated with proton-consuming acid resistance system 2 (AR2), protein chaperone HdeB, and reactive oxygen species (ROS) removal in the exponential phase. This study illustrated that the fine-tuning of sRNAs and their chaperones can be a novel strategy for improving the acid tolerance of E. coli IMPORTANCE Many of the traditional studies on bacterial acid tolerance generally focused on improving cell survival under extreme-pH conditions, but cell growth under less harsh acidic conditions is more relevant to industrial applications. Under normal conditions, the general stress response sigma factor RpoS is maintained at low levels in the growth phase through a number of mechanisms. This study showed that RpoS can be activated prior to the stationary phase via engineering its activators, the sRNA DsrA and the sRNA chaperone Hfq, resulting in significantly improved cell growth at modest acidic pH. This work suggests that the sigma factors and likely other transcription factors can be retuned or retimed by manipulating the respective regulatory sRNAs along with the sufficient supply of the respective sRNA chaperones (i.e., Hfq). This provides a novel avenue for strain engineering of microbes.
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