1
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Huang RL, Jewel D, Kelemen RE, Pham Q, Yared TJ, Wang S, Singha Roy SJ, Huang Z, Levinson SD, Sundaresh B, Miranda SE, van Opijnen T, Chatterjee A. Directed Evolution of a Bacterial Leucyl tRNA in Mammalian Cells for Enhanced Noncanonical Amino Acid Mutagenesis. ACS Synth Biol 2024. [PMID: 38904157 DOI: 10.1021/acssynbio.4c00196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
The Escherichia coli leucyl-tRNA synthetase (EcLeuRS)/tRNAEcLeu pair has been engineered to genetically encode a structurally diverse group of enabling noncanonical amino acids (ncAAs) in eukaryotes, including those with bioconjugation handles, environment-sensitive fluorophores, photocaged amino acids, and native post-translational modifications. However, the scope of this toolbox in mammalian cells is limited by the poor activity of tRNAEcLeu. Here, we overcome this limitation by evolving tRNAEcLeu directly in mammalian cells by using a virus-assisted selection scheme. This directed evolution platform was optimized for higher throughput such that the entire acceptor stem of tRNAEcLeu could be simultaneously engineered, which resulted in the identification of several variants with remarkably improved efficiency for incorporating a wide range of ncAAs. The advantage of the evolved leucyl tRNAs was demonstrated by expressing ncAA mutants in mammalian cells that were challenging to express before using the wild-type tRNAEcLeu, by creating viral vectors that facilitated ncAA mutagenesis at a significantly lower dose and by creating more efficient mammalian cell lines stably expressing the ncAA-incorporation machinery.
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Affiliation(s)
- Rachel L Huang
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Delilah Jewel
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Rachel E Kelemen
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Quan Pham
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Tarah J Yared
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Shu Wang
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | | | - Zeyi Huang
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Samantha D Levinson
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Bharathi Sundaresh
- Biology Department, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | | | - Tim van Opijnen
- Biology Department, Boston College, Chestnut Hill, Massachusetts 02467, United States
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Abhishek Chatterjee
- Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States
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2
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Guo QR, Cao YJ. Applications of genetic code expansion technology in eukaryotes. Protein Cell 2024; 15:331-363. [PMID: 37847216 PMCID: PMC11074999 DOI: 10.1093/procel/pwad051] [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: 07/04/2023] [Accepted: 09/26/2023] [Indexed: 10/18/2023] Open
Abstract
Unnatural amino acids (UAAs) have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to proteins. In eukaryotes, genetic code expansion (GCE) enables the incorporation of UAAs and facilitates posttranscriptional modification (PTM), which is not feasible in prokaryotic systems. GCE is also a powerful tool for cell or animal imaging, the monitoring of protein interactions in target cells, drug development, and switch regulation. Therefore, there is keen interest in utilizing GCE in eukaryotic systems. This review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.
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Affiliation(s)
- Qiao-ru Guo
- State Key Laboratory of Chemical Oncogenomic, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Yu J Cao
- State Key Laboratory of Chemical Oncogenomic, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
- Institute of Chemical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
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3
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Osgood AO, Roy SJS, Koo D, Gu R, Chatterjee A. A Genetically Encoded Photocaged Cysteine for Facile Site-Specific Introduction of Conjugation-Ready Thiol Residues in Antibodies. Bioconjug Chem 2024; 35:457-464. [PMID: 38548654 DOI: 10.1021/acs.bioconjchem.3c00513] [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] [Indexed: 04/18/2024]
Abstract
Antibody-drug conjugates (ADCs) have emerged as a powerful class of anticancer therapeutics that enable the selective delivery of toxic payloads into target cells. There is increasing appreciation for the importance of synthesizing such ADCs in a defined manner where the payload is attached at specific permissive sites on the antibody with a defined drug to antibody ratio. Additionally, the ability to systematically alter the site of attachment is important to fine-tune the therapeutic properties of the ADC. Engineered cysteine residues have been used to achieve such site-specific programmable attachment of drug molecules onto antibodies. However, engineered cysteine residues on antibodies often get "disulfide-capped" during secretion and require reductive regeneration prior to conjugation. This reductive step also reduces structurally important disulfide bonds in the antibody itself, which must be regenerated through oxidation. This multistep, cumbersome process reduces the efficiency of conjugation and presents logistical challenges. Additionally, certain engineered cysteine sites are resistant to reductive regeneration, limiting their utility and the overall scope of this conjugation strategy. In this work, we utilize a genetically encoded photocaged cysteine residue that can be site-specifically installed into the antibody. This photocaged amino acid can be efficiently decaged using light, revealing a free cysteine residue available for conjugation without disrupting the antibody structure. We show that this ncAA can be incorporated at several positions within full-length recombinant trastuzumab and decaged efficiently. We further used this method to generate a functional ADC site-specifically modified with monomethyl auristatin F (MMAF).
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Affiliation(s)
- Arianna O Osgood
- Department of Chemistry, Boston College, 2609 Beacon Street, 201 Merkert Chemistry Center, Chestnut Hill, Massachusetts 02467, United States
| | - Soumya Jyoti Singha Roy
- Department of Chemistry, Boston College, 2609 Beacon Street, 201 Merkert Chemistry Center, Chestnut Hill, Massachusetts 02467, United States
| | - David Koo
- Department of Chemistry, Boston College, 2609 Beacon Street, 201 Merkert Chemistry Center, Chestnut Hill, Massachusetts 02467, United States
| | - Renpeng Gu
- Department of Chemistry, Boston College, 2609 Beacon Street, 201 Merkert Chemistry Center, Chestnut Hill, Massachusetts 02467, United States
| | - Abhishek Chatterjee
- Department of Chemistry, Boston College, 2609 Beacon Street, 201 Merkert Chemistry Center, Chestnut Hill, Massachusetts 02467, United States
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4
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Davey-Young J, Hasan F, Tennakoon R, Rozik P, Moore H, Hall P, Cozma E, Genereaux J, Hoffman KS, Chan PP, Lowe TM, Brandl CJ, O’Donoghue P. Mistranslating the genetic code with leucine in yeast and mammalian cells. RNA Biol 2024; 21:1-23. [PMID: 38629491 PMCID: PMC11028032 DOI: 10.1080/15476286.2024.2340297] [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] [Accepted: 04/03/2024] [Indexed: 04/19/2024] Open
Abstract
Translation fidelity relies on accurate aminoacylation of transfer RNAs (tRNAs) by aminoacyl-tRNA synthetases (AARSs). AARSs specific for alanine (Ala), leucine (Leu), serine, and pyrrolysine do not recognize the anticodon bases. Single nucleotide anticodon variants in their cognate tRNAs can lead to mistranslation. Human genomes include both rare and more common mistranslating tRNA variants. We investigated three rare human tRNALeu variants that mis-incorporate Leu at phenylalanine or tryptophan codons. Expression of each tRNALeu anticodon variant in neuroblastoma cells caused defects in fluorescent protein production without significantly increased cytotoxicity under normal conditions or in the context of proteasome inhibition. Using tRNA sequencing and mass spectrometry we confirmed that each tRNALeu variant was expressed and generated mistranslation with Leu. To probe the flexibility of the entire genetic code towards Leu mis-incorporation, we created 64 yeast strains to express all possible tRNALeu anticodon variants in a doxycycline-inducible system. While some variants showed mild or no growth defects, many anticodon variants, enriched with G/C at positions 35 and 36, including those replacing Leu for proline, arginine, alanine, or glycine, caused dramatic reductions in growth. Differential phenotypic defects were observed for tRNALeu mutants with synonymous anticodons and for different tRNALeu isoacceptors with the same anticodon. A comparison to tRNAAla anticodon variants demonstrates that Ala mis-incorporation is more tolerable than Leu at nearly every codon. The data show that the nature of the amino acid substitution, the tRNA gene, and the anticodon are each important factors that influence the ability of cells to tolerate mistranslating tRNAs.
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Affiliation(s)
- Josephine Davey-Young
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Farah Hasan
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Rasangi Tennakoon
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Peter Rozik
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Henry Moore
- Department of Biomolecular Engineering, Baskin School of Engineering & UCSC Genomics Institute, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Peter Hall
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Ecaterina Cozma
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Julie Genereaux
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | | | - Patricia P. Chan
- Department of Biomolecular Engineering, Baskin School of Engineering & UCSC Genomics Institute, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Todd M. Lowe
- Department of Biomolecular Engineering, Baskin School of Engineering & UCSC Genomics Institute, University of California Santa Cruz, Santa Cruz, CA, USA
| | - Christopher J. Brandl
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
| | - Patrick O’Donoghue
- Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada
- Department of Chemistry, The University of Western Ontario, London, Ontario, Canada
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5
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Yang X, Zhao L, Wang Y, Ji Y, Su XC, Ma JA, Xuan W. Constructing Photoactivatable Protein with Genetically Encoded Photocaged Glutamic Acid. Angew Chem Int Ed Engl 2023; 62:e202308472. [PMID: 37587083 DOI: 10.1002/anie.202308472] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 07/28/2023] [Accepted: 08/16/2023] [Indexed: 08/18/2023]
Abstract
Genetically replacing an essential residue with the corresponding photocaged analogues via genetic code expansion (GCE) constitutes a useful and unique strategy to directly and effectively generate photoactivatable proteins. However, the application of this strategy is severely hampered by the limited number of encoded photocaged proteinogenic amino acids. Herein, we report the genetic incorporation of photocaged glutamic acid analogues in E. coli and mammalian cells and demonstrate their use in constructing photoactivatable variants of various fluorescent proteins and SpyCatcher. We believe genetically encoded photocaged Glu would significantly promote the design and application of photoactivatable proteins in many areas.
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Affiliation(s)
- Xiaochen Yang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Lei Zhao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Ying Wang
- School of Life Sciences, Tianjin University, Tianjin, 300072, China
| | - Yanli Ji
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Xun-Cheng Su
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Jun-An Ma
- Department of Chemistry, Frontier Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, 300072, P. R. China
| | - Weimin Xuan
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
- School of Life Sciences, Tianjin University, Tianjin, 300072, China
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6
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Chaudière J. Biological and Catalytic Properties of Selenoproteins. Int J Mol Sci 2023; 24:10109. [PMID: 37373256 DOI: 10.3390/ijms241210109] [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] [Received: 05/04/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Selenocysteine is a catalytic residue at the active site of all selenoenzymes in bacteria and mammals, and it is incorporated into the polypeptide backbone by a co-translational process that relies on the recoding of a UGA termination codon into a serine/selenocysteine codon. The best-characterized selenoproteins from mammalian species and bacteria are discussed with emphasis on their biological function and catalytic mechanisms. A total of 25 genes coding for selenoproteins have been identified in the genome of mammals. Unlike the selenoenzymes of anaerobic bacteria, most mammalian selenoenzymes work as antioxidants and as redox regulators of cell metabolism and functions. Selenoprotein P contains several selenocysteine residues and serves as a selenocysteine reservoir for other selenoproteins in mammals. Although extensively studied, glutathione peroxidases are incompletely understood in terms of local and time-dependent distribution, and regulatory functions. Selenoenzymes take advantage of the nucleophilic reactivity of the selenolate form of selenocysteine. It is used with peroxides and their by-products such as disulfides and sulfoxides, but also with iodine in iodinated phenolic substrates. This results in the formation of Se-X bonds (X = O, S, N, or I) from which a selenenylsulfide intermediate is invariably produced. The initial selenolate group is then recycled by thiol addition. In bacterial glycine reductase and D-proline reductase, an unusual catalytic rupture of selenium-carbon bonds is observed. The exchange of selenium for sulfur in selenoproteins, and information obtained from model reactions, suggest that a generic advantage of selenium compared with sulfur relies on faster kinetics and better reversibility of its oxidation reactions.
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Affiliation(s)
- Jean Chaudière
- CBMN (CNRS, UMR 5248), University of Bordeaux, 33600 Pessac, France
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7
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Chung CZ, Krahn N. The selenocysteine toolbox: A guide to studying the 21st amino acid. Arch Biochem Biophys 2022; 730:109421. [DOI: 10.1016/j.abb.2022.109421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/22/2022] [Accepted: 09/26/2022] [Indexed: 11/28/2022]
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8
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Liao P, Liu H, He C. Chemical synthesis of human selenoprotein F and elucidation of its thiol-disulfide oxidoreductase activity. Chem Sci 2022; 13:6322-6327. [PMID: 35733894 PMCID: PMC9159075 DOI: 10.1039/d2sc00492e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 05/06/2022] [Indexed: 01/16/2023] Open
Abstract
Selenoprotein F (SelF) is an endoplasmic reticulum-residing eukaryotic protein that contains a selenocysteine (Sec) residue. It has been suggested to be involved in a number of physiological processes by acting as a thiol-disulfide oxidoreductase, but the exact role has remained unclear due to the lack of a reliable production method. We document herein a robust synthesis of the human SelF through a three-segment two-ligation semisynthesis strategy. Highlighted in this synthetic route are the use of a mild desulfurization process to protect the side-chain of the Sec residue from being affected and the simultaneous removal of acetamidomethyl and p-methoxybenzyl protection groups by PdCl2, thus facilitating the synthesis of multi-milligrams of homogenous SelF. The reduction potential of SelF was determined and the thiol-disulfide oxidoreductase activity was further supported by its ability to catalyze the reduction and isomerization of disulfide bonds.
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Affiliation(s)
- Peisi Liao
- School of Chemistry and Chemical Engineering, South China University of Technology Guangzhou 510640 China
| | - Hongmei Liu
- Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology Wuhan 430074 China
- Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518057 China
| | - Chunmao He
- School of Chemistry and Chemical Engineering, South China University of Technology Guangzhou 510640 China
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9
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Expressing recombinant selenoproteins using redefinition of a single UAG codon in an RF1-depleted E. coli host strain. Methods Enzymol 2022; 662:95-118. [PMID: 35101220 DOI: 10.1016/bs.mie.2021.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Selenoproteins containing the rare amino acid selenocysteine (Sec), typically being enzymes utilizing the selenium atom of Sec for promoted catalysis of redox reactions, are challenging to obtain at high amounts in pure form. The technical challenges limiting selenoprotein supply derive from intricacies in their translation, necessitating the recoding of a UGA stop codon to a sense codon for Sec. This, in turn, involves the interactions of a Sec-dedicated elongation factor, either directly or indirectly, with a structure in the selenoprotein-encoding mRNA called a SECIS element (Selenocysteine Insertion Sequence), a dedicated tRNA species for Sec with an anticodon for the UGA, and several accessory enzymes and proteins involved in the selenoprotein synthesis. Here, we describe an alternative method for recombinant selenoprotein production using UAG as the Sec codon in a specific strain of E. coli lacking other UAG codons and lacking the release factor RF1 that normally terminates translation at UAG. We also describe how such recombinant selenoproteins can be purified and further analyzed for final Sec contents. The methodology can be used for production of natural selenoproteins in recombinant form as well as for production of synthetic selenoproteins that may be designed to use the unique biophysical properties of Sec for diverse biotechnological applications.
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10
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Bedding MJ, Kulkarni SS, Payne RJ. Diselenide-selenoester ligation in the chemical synthesis of proteins. Methods Enzymol 2022; 662:363-399. [PMID: 35101218 DOI: 10.1016/bs.mie.2021.10.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Peptides and proteins represent an important class of biomolecules responsible for a plethora of structural and functional roles in vivo. Following their translation on the ribosome, the majority of eukaryotic proteins are post-translationally modified, leading to a proteome that is much larger than the number of genes present in a given organism. In order to understand the functional role of a given protein modification, it is necessary to access peptides and proteins bearing homogeneous and site-specific modifications. Accordingly, there has been significant research effort centered on the development of peptide ligation methodologies for the chemical synthesis of modified proteins. In this chapter we outline the discovery and development of a contemporary methodology called the diselenide-selenoester ligation (DSL) that enables the rapid and efficient fusion of peptide fragments to generate synthetic proteins. The practical aspects of using DSL for the preparation of chemically modified peptides and proteins in the laboratory is described. In addition, recent advances in the application of the methodology are outlined, exemplified by the synthesis and biological evaluation of a number of complex protein targets.
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Affiliation(s)
- Max J Bedding
- School of Chemistry, The University of Sydney, Camperdown, NSW, Australia; Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Camperdown, NSW, Australia
| | - Sameer S Kulkarni
- School of Chemistry, The University of Sydney, Camperdown, NSW, Australia; Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Camperdown, NSW, Australia
| | - Richard J Payne
- School of Chemistry, The University of Sydney, Camperdown, NSW, Australia; Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Camperdown, NSW, Australia.
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11
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Hartman MCT. Non-canonical Amino Acid Substrates of E. coli Aminoacyl-tRNA Synthetases. Chembiochem 2022; 23:e202100299. [PMID: 34416067 PMCID: PMC9651912 DOI: 10.1002/cbic.202100299] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/03/2021] [Indexed: 01/07/2023]
Abstract
In this comprehensive review, I focus on the twenty E. coli aminoacyl-tRNA synthetases and their ability to charge non-canonical amino acids (ncAAs) onto tRNAs. The promiscuity of these enzymes has been harnessed for diverse applications including understanding and engineering of protein function, creation of organisms with an expanded genetic code, and the synthesis of diverse peptide libraries for drug discovery. The review catalogues the structures of all known ncAA substrates for each of the 20 E. coli aminoacyl-tRNA synthetases, including ncAA substrates for engineered versions of these enzymes. Drawing from the structures in the list, I highlight trends and novel opportunities for further exploitation of these ncAAs in the engineering of protein function, synthetic biology, and in drug discovery.
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Affiliation(s)
- Matthew C T Hartman
- Department of Chemistry and Massey Cancer Center, Virginia Commonwealth University, 1001 W Main St., Richmond, VA 23220, USA
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12
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SecMS analysis of selenoproteins with selenocysteine insertion sequence and beyond. Methods Enzymol 2022; 662:227-240. [DOI: 10.1016/bs.mie.2021.10.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Abstract
Selenoproteins, which contain the 21st amino acid selenocysteine, play roles in maintaining cellular redox homeostasis. Many open questions remain in the field of selenoprotein biology, including the functions of a number of uncharacterized human selenoproteins, and the properties of selenocysteine compared to its analogous amino acid cysteine. The mechanism of selenocysteine incorporation involves an intricate machinery that deviates from the mechanism of incorporation for the canonical 20 amino acids. As a result, recombinant expression of selenoproteins has been historically challenging, and has hindered a deeper evaluation of selenoprotein biology. Genetic code expansion methods, which incorporate protected analogs of selenocysteine, allow the endogenous selenocysteine incorporation mechanism to be bypassed entirely to facilitate selenoprotein expression. Here we present a method for incorporating a photocaged selenocysteine amino acid (DMNB-Sec) into human selenoproteins directly in mammalian cells. This approach offers the opportunity to study human selenoproteins in their native cellular environment and should advance our understanding of selenoprotein biology.
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14
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Chung CZ, Miller C, Söll D, Krahn N. Introducing Selenocysteine into Recombinant Proteins in Escherichia coli. Curr Protoc 2021; 1:e54. [PMID: 33566458 DOI: 10.1002/cpz1.54] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Selenoproteins contain the 21st amino acid, selenocysteine. Selenocysteine is the only amino acid that is synthesized on its cognate tRNA, and it is inserted at specific recoded UGA stop codons via a complex translation system. Although highly similar to cysteine, selenocysteine has unique properties, including a stronger nucleophilic ability and lower reduction potential. Efforts to site-specifically incorporate selenocysteine to create recombinant selenoproteins involve a recoded UAG stop codon and expression of the necessary selenocysteine translation machinery. This article presents a protocol for expressing and purifying selenoproteins in Escherichia coli. © 2021 Wiley Periodicals LLC. Basic Protocol: Recombinant selenoprotein production in E. coli using a rewired translation system.
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Affiliation(s)
- Christina Z Chung
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut
| | - Corwin Miller
- Department of Biosciences, Rice University, Houston, Texas
| | - Dieter Söll
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut.,Department of Chemistry, Yale University, New Haven, Connecticut
| | - Natalie Krahn
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut
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15
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Wang Y, Liu P, Chang J, Xu Y, Wang J. Site-Specific Selenocysteine Incorporation into Proteins by Genetic Engineering. Chembiochem 2021; 22:2918-2924. [PMID: 33949764 DOI: 10.1002/cbic.202100124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/03/2021] [Indexed: 01/23/2023]
Abstract
Selenocysteine (Sec), a rare naturally proteinogenic amino acid, is the major form of essential trace element selenium in living organisms. Selenoproteins, with one or several Sec residues, are found in all three domains of life. Many selenoproteins play a role in critical cellular functions such as maintaining cell redox homeostasis. Sec is usually encoded by an in-frame stop codon UGA in the selenoprotein mRNA, and its incorporation in vivo is highly species-dependent and requires the reprogramming of translation. This mechanistic complexity of selenoprotein synthesis poses a big challenge to produce synthetic selenoproteins. To understand the functions of natural as well as engineered selenoproteins, many strategies have recently been developed to overcome the inherent barrier for recombinant selenoprotein production. In this review, we will describe the progress in selenoprotein production methodology.
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Affiliation(s)
- Yuchuan Wang
- Shenzhen Institute of Transfusion Medicine Shenzhen Blood Center, Shenzhen, Futian District, 518052, P. R. China.,Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen, Nanshan District, 518055, P. R. China
| | - Pengcheng Liu
- Institute of Biophysics, Chinese Academy of Sciences, Beijing, Chaoyang District, 100101, P. R. China
| | - Jiao Chang
- Institute of Biophysics, Chinese Academy of Sciences, Beijing, Chaoyang District, 100101, P. R. China
| | - Yunping Xu
- Shenzhen Institute of Transfusion Medicine Shenzhen Blood Center, Shenzhen, Futian District, 518052, P. R. China
| | - Jiangyun Wang
- Shenzhen Institute of Transfusion Medicine Shenzhen Blood Center, Shenzhen, Futian District, 518052, P. R. China.,Institute of Biophysics, Chinese Academy of Sciences, Beijing, Chaoyang District, 100101, P. R. China.,Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen, Nanshan District, 518055, P. R. China
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16
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Rakauskaitė R, Urbanavičiūtė G, Simanavičius M, Lasickienė R, Vaitiekaitė A, Petraitytė G, Masevičius V, Žvirblienė A, Klimašauskas S. Photocage-Selective Capture and Light-Controlled Release of Target Proteins. iScience 2020; 23:101833. [PMID: 33305188 PMCID: PMC7718476 DOI: 10.1016/j.isci.2020.101833] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/10/2020] [Accepted: 11/16/2020] [Indexed: 12/05/2022] Open
Abstract
Photochemical transformations enable exquisite spatiotemporal control over biochemical processes; however, methods for reliable manipulations of biomolecules tagged with biocompatible photo-sensitive reporters are lacking. Here we created a high-affinity binder specific to a photolytically removable caging group. We utilized chemical modification or genetically encoded incorporation of noncanonical amino acids to produce proteins with photocaged cysteine or selenocysteine residues, which were used for raising a high-affinity monoclonal antibody against a small photoremovable tag, 4,5-dimethoxy-2-nitrobenzyl (DMNB) group. Employing the produced photocage-selective binder, we demonstrate selective detection and immunoprecipitation of a variety of DMNB-caged target proteins in complex biological mixtures. This combined orthogonal strategy permits photocage-selective capture and light-controlled traceless release of target proteins for a myriad of applications in nanoscale assays. The first high-affinity monoclonal antibody specific for a popular photocaging group A new tool for selective detection of DMNB-tagged proteins in complex mixtures Enables non-covalent capture of native proteins with surface-exposed DMNB groups Orthogonal protein manipulation by photocage-selective capture and photolytic release
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Affiliation(s)
- Rasa Rakauskaitė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Giedrė Urbanavičiūtė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Martynas Simanavičius
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Rita Lasickienė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Aušra Vaitiekaitė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Gražina Petraitytė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania.,Institute of Chemistry, Department of Chemistry and Geosciences, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Viktoras Masevičius
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania.,Institute of Chemistry, Department of Chemistry and Geosciences, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Aurelija Žvirblienė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Saulius Klimašauskas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, LT-10257 Vilnius, Lithuania
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17
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Mao X, Li P, Li T, Zhao M, Chen C, Liu J, Wang Z, Yu L. Inhibition of mycotoxin deoxynivalenol generation by using selenized glucose. CHINESE CHEM LETT 2020. [DOI: 10.1016/j.cclet.2020.06.033] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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18
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A FRET-ICT Dual-Modulated Ratiometric Fluorescence Sensor for Monitoring and Bio-Imaging of Cellular Selenocysteine. Molecules 2020; 25:molecules25214999. [PMID: 33126726 PMCID: PMC7663636 DOI: 10.3390/molecules25214999] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/11/2020] [Accepted: 10/27/2020] [Indexed: 12/27/2022] Open
Abstract
Since the fluctuation of cellular selenocysteine (Sec) concentration plays an all-important role in the development of numerous human disorders, the real-time fluorescence detection of Sec in living systems has attracted plenty of interest during the past decade. In order to obtain a faster and more sensitive small organic molecule fluorescence sensor for the Sec detection, a new ratiometric fluorescence sensor Q7 was designed based on the fluorescence resonance energy transfer (FRET) strategy with coumarin fluorophore as energy donor and 4-hydroxy naphthalimide fluorophore (with 2,4-dinitrobenzene sulfonate as fluorescence signal quencher and Sec-selective recognition site) as an energy acceptor. The sensor Q7 exhibited only a blue fluorescence signal, and displayed two well distinguished emission bands (blue and green) in the presence of Sec with ∆λ of 68 nm. Moreover, concentrations ranging of quantitative detection of Sec of Q7 was from 0 to 45 μM (limit of detection = 6.9 nM), with rapid ratiometric response, high sensitivity and selectivity capability. Impressively, the results of the living cell imaging test demonstrated Q7 has the potentiality of being an ideal sensor for real-time Sec detection in biosystems.
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