1
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Schene ME, Infield DT, Ahern CA. Expression and purification of fluorinated proteins from mammalian suspension culture. Methods Enzymol 2024; 696:341-354. [PMID: 38658087 DOI: 10.1016/bs.mie.2024.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
The site-specific encoding of noncanonical amino acids allows for the introduction of rationalized chemistry into a target protein. Of the methods that enable this technology, evolved tRNA and synthetase pairs offer the potential for expanded protein production and purification. Such an approach combines the versatility of solid-phase peptide synthesis with the scalable features of recombinant protein production. We describe the large scale production and purification of eukaryotic proteins bearing fluorinated phenylalanine in mammalian suspension cell preparations. Downstream applications of this approach include scalable recombinant protein preparation for ligand binding assays with small molecules and ligands, protein structure determination, and protein stability assays.
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Affiliation(s)
- Miranda E Schene
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA
| | - Daniel T Infield
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA
| | - Christopher A Ahern
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA.
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2
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Knowles OJ, Johannissen LO, Crisenza GEM, Hay S, Leys D, Procter DJ. A Vitamin B 2 -Photocatalysed Approach to Methionine Analogues. Angew Chem Int Ed Engl 2022; 61:e202212158. [PMID: 36250805 PMCID: PMC10100050 DOI: 10.1002/anie.202212158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Indexed: 11/05/2022]
Abstract
Access to new non-canonical amino acid residues is crucial for medicinal chemistry and chemical biology. Analogues of the amino acid methionine have been far less explored-despite their use in biochemistry, pharmacology and peptide bioconjugation. This is largely due to limited synthetic access. Herein, we exploit a new disconnection to access non-natural methionines through the development of a photochemical method for the radical α-C-H functionalization of sulfides with alkenes, in water, using inexpensive and commercially-available riboflavin (vitamin B2 ) as a photocatalyst. Our photochemical conditions allow the two-step synthesis of novel methionine analogues-by radical addition to unsaturated amino acid derivatives-and the chemoselective modification of peptide side-chains to yield non-natural methionine residues within small peptides. The mechanism of the bio-inspired flavin photocatalysis has been probed by experimental, DFT and TDDFT studies.
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Affiliation(s)
- Oliver J Knowles
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Linus O Johannissen
- Manchester Institute of Biotechnology and Department of Chemistry, University of Manchester, Princess Street, Manchester, M1 7DN, UK
| | - Giacomo E M Crisenza
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Sam Hay
- Manchester Institute of Biotechnology and Department of Chemistry, University of Manchester, Princess Street, Manchester, M1 7DN, UK
| | - David Leys
- Manchester Institute of Biotechnology and Department of Chemistry, University of Manchester, Princess Street, Manchester, M1 7DN, UK
| | - David J Procter
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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3
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Knowles OJ, Johannissen LO, Crisenza GEM, Hay S, Leys D, Procter DJ. A Vitamin B 2-Photocatalysed Approach to Methionine Analogues. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 134:e202212158. [PMID: 38505624 PMCID: PMC10946832 DOI: 10.1002/ange.202212158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Indexed: 11/11/2022]
Abstract
Access to new non-canonical amino acid residues is crucial for medicinal chemistry and chemical biology. Analogues of the amino acid methionine have been far less explored-despite their use in biochemistry, pharmacology and peptide bioconjugation. This is largely due to limited synthetic access. Herein, we exploit a new disconnection to access non-natural methionines through the development of a photochemical method for the radical α-C-H functionalization of sulfides with alkenes, in water, using inexpensive and commercially-available riboflavin (vitamin B2) as a photocatalyst. Our photochemical conditions allow the two-step synthesis of novel methionine analogues-by radical addition to unsaturated amino acid derivatives-and the chemoselective modification of peptide side-chains to yield non-natural methionine residues within small peptides. The mechanism of the bio-inspired flavin photocatalysis has been probed by experimental, DFT and TDDFT studies.
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Affiliation(s)
- Oliver J. Knowles
- Department of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
| | - Linus O. Johannissen
- Manchester Institute of Biotechnology and Department of ChemistryUniversity of ManchesterPrincess StreetManchesterM1 7DNUK
| | | | - Sam Hay
- Manchester Institute of Biotechnology and Department of ChemistryUniversity of ManchesterPrincess StreetManchesterM1 7DNUK
| | - David Leys
- Manchester Institute of Biotechnology and Department of ChemistryUniversity of ManchesterPrincess StreetManchesterM1 7DNUK
| | - David J. Procter
- Department of ChemistryUniversity of ManchesterOxford RoadManchesterM13 9PLUK
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4
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Haernvall K, Fladischer P, Schoeffmann H, Zitzenbacher S, Pavkov-Keller T, Gruber K, Schick M, Yamamoto M, Kuenkel A, Ribitsch D, Guebitz GM, Wiltschi B. Residue-Specific Incorporation of the Non-Canonical Amino Acid Norleucine Improves Lipase Activity on Synthetic Polyesters. Front Bioeng Biotechnol 2022; 10:769830. [PMID: 35155387 PMCID: PMC8826565 DOI: 10.3389/fbioe.2022.769830] [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: 09/02/2021] [Accepted: 01/07/2022] [Indexed: 11/19/2022] Open
Abstract
Environmentally friendly functionalization and recycling processes for synthetic polymers have recently gained momentum, and enzymes play a central role in these procedures. However, natural enzymes must be engineered to accept synthetic polymers as substrates. To enhance the activity on synthetic polyesters, the canonical amino acid methionine in Thermoanaerobacter thermohydrosulfuricus lipase (TTL) was exchanged by the residue-specific incorporation method for the more hydrophobic non-canonical norleucine (Nle). Strutural modelling of TTL revealed that residues Met-114 and Met-142 are in close vicinity of the active site and their replacement by the norleucine could modulate the catalytic activity of the enzyme. Indeed, hydrolysis of the polyethylene terephthalate model substrate by the Nle variant resulted in significantly higher amounts of release products than the Met variant. A similar trend was observed for an ionic phthalic polyester containing a short alkyl diol (C5). Interestingly, a 50% increased activity was found for TTL [Nle] towards ionic phthalic polyesters containing different ether diols compared to the parent enzyme TTL [Met]. These findings clearly demonstrate the high potential of non-canonical amino acids for enzyme engineering.
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Affiliation(s)
| | - Patrik Fladischer
- Acib–Austrian Centre of Industrial Biotechnology, Graz, Austria
- Institute of Molecular Biotechnology, Graz University of Technology, Graz, Austria
| | | | | | - Tea Pavkov-Keller
- Acib–Austrian Centre of Industrial Biotechnology, Graz, Austria
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
- Field of Excellence BioHealth—University of Graz, Graz, Austria
| | - Karl Gruber
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
- Field of Excellence BioHealth—University of Graz, Graz, Austria
| | | | | | | | - Doris Ribitsch
- Acib–Austrian Centre of Industrial Biotechnology, Graz, Austria
- Institute for Environmental Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
- *Correspondence: Doris Ribitsch,
| | - Georg M. Guebitz
- Acib–Austrian Centre of Industrial Biotechnology, Graz, Austria
- Institute for Environmental Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Birgit Wiltschi
- Acib–Austrian Centre of Industrial Biotechnology, Graz, Austria
- Institute of Molecular Biotechnology, Graz University of Technology, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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5
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Stieglitz JT, Potts KA, Van Deventer JA. Broadening the Toolkit for Quantitatively Evaluating Noncanonical Amino Acid Incorporation in Yeast. ACS Synth Biol 2021; 10:3094-3104. [PMID: 34730946 DOI: 10.1021/acssynbio.1c00370] [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] [Indexed: 11/28/2022]
Abstract
Genetic code expansion is a powerful approach for advancing critical fields such as biological therapeutic discovery. However, the machinery for genetically encoding noncanonical amino acids (ncAAs) is only available in limited plasmid formats, constraining potential applications. In extreme cases, the introduction of two separate plasmids, one containing an orthogonal translation system (OTS) to facilitate ncAA incorporation and a second for expressing a ncAA-containing protein of interest, is not possible due to a lack of the available selection markers. One strategy to circumvent this challenge is to express the OTS and protein of interest from a single vector. For what we believe is the first time in yeast, we describe here several sets of single plasmid systems (SPSs) for performing genetic code manipulation and compare the ncAA incorporation capabilities of these plasmids against the capabilities of previously described dual plasmid systems (DPSs). For both dual fluorescent protein reporters and yeast display reporters tested with multiple OTSs and ncAAs, measured ncAA incorporation efficiencies with SPSs were determined to be equal to efficiencies determined with DPSs. Click chemistry on yeast cells displaying ncAA-containing proteins was also shown to be feasible in both formats, although differences in reactivity between formats suggest the need for caution when using such approaches. Additionally, we investigated whether these reporters would support the separation of yeast strains known to exhibit distinct ncAA incorporation efficiencies. Model sorts conducted with mixtures of two strains transformed with the same SPS or DPS both led to the enrichment of a strain known to support a higher efficiency ncAA incorporation, suggesting that these reporters will be suitable for conducting screens for strains exhibiting enhanced ncAA incorporation efficiencies. Overall, our results confirm that SPSs are well behaved in yeast and provide a convenient alternative to DPSs. SPSs are expected to be invaluable for conducting high-throughput investigations of the effects of genetic or genomic changes on ncAA incorporation efficiency and, more fundamentally, the eukaryotic translation apparatus.
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Affiliation(s)
- Jessica T. Stieglitz
- Chemical and Biological Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
| | - Kelly A. Potts
- Chemical and Biological Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
| | - James A. Van Deventer
- Chemical and Biological Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
- Biomedical Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
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6
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Zhu HQ, Tang XL, Zheng RC, Zheng YG. Recent advancements in enzyme engineering via site-specific incorporation of unnatural amino acids. World J Microbiol Biotechnol 2021; 37:213. [PMID: 34741210 DOI: 10.1007/s11274-021-03177-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 10/23/2021] [Indexed: 11/28/2022]
Abstract
With increased attention to excellent biocatalysts, evolving methods based on nature or unnatural amino acid (UAAs) mutagenesis have become an important part of enzyme engineering. The emergence of powerful method through expanding the genetic code allows to incorporate UAAs with unique chemical functionalities into proteins, endowing proteins with more structural and functional features. To date, over 200 diverse UAAs have been incorporated site-specifically into proteins via this methodology and many of them have been widely exploited in the field of enzyme engineering, making this genetic code expansion approach possible to be a promising tool for modulating the properties of enzymes. In this context, we focus on how this robust method to specifically incorporate UAAs into proteins and summarize their applications in enzyme engineering for tuning and expanding the functional properties of enzymes. Meanwhile, we aim to discuss how the benefits can be achieved by using the genetically encoded UAAs. We hope that this method will become an integral part of the field of enzyme engineering in the future.
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Affiliation(s)
- Hang-Qin Zhu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.,Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China
| | - Xiao-Ling Tang
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.,Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China
| | - Ren-Chao Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China. .,Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.
| | - Yu-Guo Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.,Engineering Research Center of Bioconversion and Biopurification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China
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7
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Edelstein EK, Rankic DA, Dudley CC, McMinn SE, Adpressa DA. Synthesis of Proline Analogues via Rh-Catalyzed Asymmetric Conjugate Addition. ACS Catal 2020. [DOI: 10.1021/acscatal.0c04648] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Emma K. Edelstein
- Department of Process Research and Development, Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | - Danica A. Rankic
- Department of Process Research and Development, Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | - Caroline C. Dudley
- Department of Process Research and Development, Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | - Spencer E. McMinn
- Department of Discovery Chemistry, Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | - Donovon A. Adpressa
- Department of Process Research and Development, Merck & Co., Inc., Boston, Massachusetts 02115, United States
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8
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Tobola F, Sylvander E, Gafko C, Wiltschi B. 'Clickable lectins': bioorthogonal reactive handles facilitate the directed conjugation of lectins in a modular fashion. Interface Focus 2019; 9:20180072. [PMID: 30842873 DOI: 10.1098/rsfs.2018.0072] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2018] [Indexed: 01/07/2023] Open
Abstract
Lectins are carbohydrate-binding proteins with specificity for their target ligands. They play diverse roles in cellular recognition and signalling processes, as well as in infections and cancer metastasis. Owing to their specificity, lectins find application in biotechnology and medicine, e.g. for blood group typing, purification of glycoproteins or lipids and as markers that target cancer cells. For some applications, lectins are immobilized on a solid support, or they are conjugated with other molecules. Classical protein conjugation reactions at nucleophilic amino acids such as cysteine or lysine are often non-selective, and the site of conjugation is difficult to pre-define. Random conjugation, however, can interfere with protein function. Therefore, we sought to equip lectins with a unique reactive handle, which can be conjugated with other molecules in a pre-defined manner. We site-specifically introduced non-canonical amino acids carrying bioorthogonal reactive groups into several lectins. As a proof of principle, we conjugated these 'clickable lectins' with small molecules. Furthermore, we conjugated lectins with different ligand specificities with one another to produce superlectins. The 'clickable lectins' might be useful for any process where lectins shall be conjugated with another module in a selective, pre-defined and site-specific manner.
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Affiliation(s)
- Felix Tobola
- Austrian Centre of Industrial Biotechnology, Petersgasse 14, 8010 Graz, Austria.,Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, 8010 Graz, Austria
| | - Elise Sylvander
- Austrian Centre of Industrial Biotechnology, Petersgasse 14, 8010 Graz, Austria
| | - Claudia Gafko
- Austrian Centre of Industrial Biotechnology, Petersgasse 14, 8010 Graz, Austria.,Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, 8010 Graz, Austria
| | - Birgit Wiltschi
- Austrian Centre of Industrial Biotechnology, Petersgasse 14, 8010 Graz, Austria
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9
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Stieglitz JT, Kehoe HP, Lei M, Van Deventer JA. A Robust and Quantitative Reporter System To Evaluate Noncanonical Amino Acid Incorporation in Yeast. ACS Synth Biol 2018; 7:2256-2269. [PMID: 30139255 PMCID: PMC6214617 DOI: 10.1021/acssynbio.8b00260] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Engineering protein translation machinery to incorporate noncanonical amino acids (ncAAs) into proteins has advanced applications ranging from proteomics to single-molecule studies. As applications of ncAAs emerge, efficient ncAA incorporation is crucial to exploiting unique chemistries. We have established a quantitative reporter platform to evaluate ncAA incorporation in response to the TAG (amber) codon in yeast. This yeast display-based reporter utilizes an antibody fragment containing an amber codon at which a ncAA is incorporated when the appropriate orthogonal translation system (OTS) is present. Epitope tags at both termini allow for flow cytometry-based end point readouts of OTS efficiency and fidelity. Using this reporter, we evaluated several factors that influence amber suppression, including the amber codon position and different aminoacyl-tRNA synthetase/tRNA (aaRS/tRNA) pairs. Interestingly, previously described aaRSs that evolved from different parent enzymes to incorporate O-methyl-l-tyrosine exhibit vastly different behavior. Escherichia coli leucyl-tRNA synthetase variants demonstrated efficient incorporation of a range of ncAAs, and we discovered unreported activities of several variants. Compared to a plate reader-based reporter, our assay yields more precise bulk-level measurements while also supporting single-cell readouts compatible with cell sorting. This platform is expected to allow quantitative elucidation of principles dictating efficient stop codon suppression and evolution of next-generation stop codon suppression systems to further enhance genetic code manipulation in eukaryotes. These efforts will improve our understanding of how the genetic code can be further evolved while expanding the range of chemical diversity available in proteins for applications ranging from fundamental epigenetics studies to engineering new classes of therapeutics.
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Affiliation(s)
- Jessica T. Stieglitz
- Chemical and Biological Engineering Department, Tufts University, Medford, MA 02155, United States
| | - Haixing P. Kehoe
- Chemical and Biological Engineering Department, Tufts University, Medford, MA 02155, United States
| | - Ming Lei
- Chemical and Biological Engineering Department, Tufts University, Medford, MA 02155, United States
| | - James A. Van Deventer
- Chemical and Biological Engineering Department, Tufts University, Medford, MA 02155, United States
- Biomedical Engineering Department, Tufts University, Medford, MA 02155, United States
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10
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Lee BS, Kim S, Ko BJ, Yoo TH. An efficient system for incorporation of unnatural amino acids in response to the four-base codon AGGA in Escherichia coli. Biochim Biophys Acta Gen Subj 2017; 1861:3016-3023. [PMID: 28212794 DOI: 10.1016/j.bbagen.2017.02.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 02/08/2017] [Accepted: 02/09/2017] [Indexed: 01/21/2023]
Abstract
BACKGROUND Adding new amino acids to the set of building blocks for protein synthesis expands the scope of protein engineering, and orthogonal pairs of tRNA and aminoacyl-tRNA synthetase have been developed for incorporating unnatural amino acids (UAAs) into proteins. While diverse systems have been developed to incorporate UAAs in response to the amber codon, less research has been focused on four-base codons despites their advantages. In this study, we report an efficient method to incorporate UAA in response to an AGGA codon in Escherichia coli. RESULTS The Methanococcus jannaschii tyrosyl-tRNA synthetase-tRNACUA(MjTyrRS-MjtRNACUA) orthogonal pair has been engineered to incorporate diverse UAAs in response to the amber codon. To apply the engineered MjTyrRS enzymes for UAAs to a four-base codon suppression, we developed an MjTyrRS-MjtRNAUCCU pair system that enabled incorporation of UAAs in response to the AGGA codon in E. coli. Using this system, we demonstrated that several UAAs could be incorporated quantitatively in the AGGA site. In addition, multiple AGGA codons were successfully suppressed in an E. coli strain when the endogenous tRNACCUArg gene was knocked out. CONCLUSION An efficient system was developed for the incorporation of UAAs in response to the AGGA four-base codon in E. coli, and the method was successfully demonstrated for several UAAs and for multiple AGGA sites. GENERAL SIGNIFICANCE The developed system can expand the repertoire of protein engineering tools based on amino acid analogues in combination with other UAA incorporation methods. This article is part of a Special Issue entitled "Biochemistry of Synthetic Biology - Recent Developments" Guest Editor: Dr. Ilka Heinemann and Dr. Patrick O'Donoghue.
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Affiliation(s)
- Byeong Sung Lee
- Department of Molecular Science and Technology, Ajou University, 206 World cup-ro, Yeongtong-gu, Suwon 16499, Republic of Korea
| | - Suyeon Kim
- Department of Molecular Science and Technology, Ajou University, 206 World cup-ro, Yeongtong-gu, Suwon 16499, Republic of Korea
| | - Byoung Joon Ko
- New Drug Development Center, Osong Medical Innovative Foundation, 123, Osongsaengmyeong-ro, Osong-eup, Cheongju 28160, Republic of Korea
| | - Tae Hyeon Yoo
- Department of Molecular Science and Technology, Ajou University, 206 World cup-ro, Yeongtong-gu, Suwon 16499, Republic of Korea; Department of Applied Chemistry and Biological Engineering, Ajou University, 206 World cup-ro, Yeongtong-gu, Suwon 16499, Republic of Korea.
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11
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Anderhuber N, Fladischer P, Gruber-Khadjawi M, Mairhofer J, Striedner G, Wiltschi B. High-level biosynthesis of norleucine in E. coli for the economic labeling of proteins. J Biotechnol 2016; 235:100-11. [PMID: 27107466 DOI: 10.1016/j.jbiotec.2016.04.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 04/14/2016] [Accepted: 04/19/2016] [Indexed: 10/21/2022]
Abstract
The residue-specific labeling of proteins with non-canonical amino acids (ncAA) is well established in shake flask cultures. A key aspect for the transfer of the methodology to larger scales for biotechnological applications is the cost of the supplemented ncAAs. Therefore, we established a scalable bioprocess using an engineered host strain for the biosynthesis of the methionine analog norleucine at titers appropriate for the efficient and economic labeling of proteins. To enhance the biosynthesis of norleucine, which is a side-product of the branched chain amino acid pathway, we deleted all three acetolactate synthase isoforms of the methionine auxotrophic Escherichia coli expression strain B834(DE3). Additionally, we overexpressed leuABCD to boost the biosynthesis of norleucine. We systematically analyzed the production of norleucine under the conditions for its residue-specific incorporation in bioreactor cultures that had a 30-fold higher cell density than shake flask cultures. Under optimized conditions, 5g/L norleucine was biosynthesized. This titer is two times higher than the standard supplementation with norleucine of a culture with comparable cell density. We expect that our metabolically engineered strain for the improved biosynthesis of norleucine in combination with the proposed bioprocess will facilitate the efficient residue-specific labeling of proteins at a reasonable price in scales beyond the shake flask.
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Affiliation(s)
- Niklaus Anderhuber
- acib-Austrian Centre of Industrial Biotechnology, Petersgasse 14, A-8010 Graz, Austria
| | - Patrik Fladischer
- acib-Austrian Centre of Industrial Biotechnology, Petersgasse 14, A-8010 Graz, Austria; Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, A-8010 Graz, Austria
| | - Mandana Gruber-Khadjawi
- acib-Austrian Centre of Industrial Biotechnology, Petersgasse 14, A-8010 Graz, Austria; Department of Organic Chemistry, Graz University of Technology, Stremayrgasse 9/4, A-8010 Graz, Austria
| | - Juergen Mairhofer
- Department of Biotechnology, University of Natural Resources and Life Sciences, and Department of Biotechnology, Muthgasse 18, A-1190 Vienna, Austria; enGenes Biotech GmbH, Mooslackengasse 17, A-1190 Vienna, Austria
| | - Gerald Striedner
- acib-Austrian Centre of Industrial Biotechnology, Petersgasse 14, A-8010 Graz, Austria; Department of Biotechnology, University of Natural Resources and Life Sciences, and Department of Biotechnology, Muthgasse 18, A-1190 Vienna, Austria
| | - Birgit Wiltschi
- acib-Austrian Centre of Industrial Biotechnology, Petersgasse 14, A-8010 Graz, Austria.
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12
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Wong HE, Pack SP, Kwon I. Positional effects of hydrophobic non-natural amino acid mutagenesis into the surface region of murine dihydrofolate reductase on enzyme properties. Biochem Eng J 2016. [DOI: 10.1016/j.bej.2015.12.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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13
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Incorporation of non-canonical amino acids into proteins in yeast. Fungal Genet Biol 2016; 89:137-156. [DOI: 10.1016/j.fgb.2016.02.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 02/01/2016] [Accepted: 02/03/2016] [Indexed: 12/22/2022]
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14
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Seo KH, Chu HS, Yoo TH, Lee SG, Won JI. Separation efficiency of free-solution conjugated electrophoresis with drag-tags incorporating a synthetic amino acid. Electrophoresis 2016; 37:818-25. [PMID: 26757485 DOI: 10.1002/elps.201500506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 12/22/2015] [Accepted: 12/29/2015] [Indexed: 11/10/2022]
Abstract
DNA sequencing or separation by conventional capillary electrophoresis with a polymer matrix has some inherent drawbacks, such as the expense of polymer matrix and limitations in sequencing read length. As DNA fragments have a linear charge-to-friction ratio in free solution, DNA fragments cannot be separated by size. However, size-based separation of DNA is possible in free-solution conjugate electrophoresis (FSCE) if a "drag-tag" is attached to DNA fragments because the tag breaks the linear charge-to-friction scaling. Although several previous studies have demonstrated the feasibility of DNA separation by free-solution conjugated electrophoresis, generation of a monodisperse drag-tag and identification of a strong, site-specific conjugation method between a DNA fragment and a drag-tag are challenges that still remain. In this study, we demonstrate an efficient FSCE method by conjugating a biologically synthesized elastin-like polypeptide (ELP) and green fluorescent protein (GFP) to DNA fragments. In addition, to produce strong and site-specific conjugation, a methionine residue in drag-tags is replaced with homopropargylglycine (Hpg), which can be conjugated specifically to a DNA fragment with an azide site.
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Affiliation(s)
- Kyung-Ho Seo
- Department of Chemical Engineering, Hongik University, Seoul, Korea
| | - Hun-Su Chu
- Department of Chemical Engineering, Hongik University, Seoul, Korea.,Material Research Center, SAMSUNG ELECTRONICS Co, Suwon, Korea
| | - Tae Hyeon Yoo
- Department of Molecular Science and Technology, Ajou University, Suwon, Korea
| | - Sun-Gu Lee
- Department of Chemical Engineering, Pusan National University, Pusan, Korea
| | - Jong-In Won
- Department of Chemical Engineering, Hongik University, Seoul, Korea
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15
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16
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Liu EJ, Sinclair A, Keefe AJ, Nannenga BL, Coyle BL, Baneyx F, Jiang S. EKylation: Addition of an Alternating-Charge Peptide Stabilizes Proteins. Biomacromolecules 2015; 16:3357-61. [DOI: 10.1021/acs.biomac.5b01031] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Erik J. Liu
- Department
of Chemical Engineering, University of Washington, Box 351750, Seattle, Washington 98195, United States
| | - Andrew Sinclair
- Department
of Chemical Engineering, University of Washington, Box 351750, Seattle, Washington 98195, United States
| | - Andrew J. Keefe
- Department
of Chemical Engineering, University of Washington, Box 351750, Seattle, Washington 98195, United States
| | - Brent L. Nannenga
- Department
of Chemical Engineering, University of Washington, Box 351750, Seattle, Washington 98195, United States
| | - Brandon L. Coyle
- Department
of Chemical Engineering, University of Washington, Box 351750, Seattle, Washington 98195, United States
| | - François Baneyx
- Department
of Chemical Engineering, University of Washington, Box 351750, Seattle, Washington 98195, United States
| | - Shaoyi Jiang
- Department
of Chemical Engineering, University of Washington, Box 351750, Seattle, Washington 98195, United States
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17
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Ravikumar Y, Nadarajan SP, Hyeon Yoo T, Lee CS, Yun H. Incorporating unnatural amino acids to engineer biocatalysts for industrial bioprocess applications. Biotechnol J 2015; 10:1862-76. [DOI: 10.1002/biot.201500153] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/13/2015] [Accepted: 09/02/2015] [Indexed: 12/22/2022]
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18
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Effects of Non-Natural Amino Acid Incorporation into the Enzyme Core Region on Enzyme Structure and Function. Int J Mol Sci 2015; 16:22735-53. [PMID: 26402667 PMCID: PMC4613333 DOI: 10.3390/ijms160922735] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 09/02/2015] [Accepted: 09/14/2015] [Indexed: 11/17/2022] Open
Abstract
Techniques to incorporate non-natural amino acids (NNAAs) have enabled biosynthesis of proteins containing new building blocks with unique structures, chemistry, and reactivity that are not found in natural amino acids. It is crucial to understand how incorporation of NNAAs affects protein function because NNAA incorporation may perturb critical function of a target protein. This study investigates how the site-specific incorporation of NNAAs affects catalytic properties of an enzyme. A NNAA with a hydrophobic and bulky sidechain, 3-(2-naphthyl)-alanine (2Nal), was site-specifically incorporated at six different positions in the hydrophobic core of a model enzyme, murine dihydrofolate reductase (mDHFR). The mDHFR variants with a greater change in van der Waals volume upon 2Nal incorporation exhibited a greater reduction in the catalytic efficiency. Similarly, the steric incompatibility calculated using RosettaDesign, a protein stability calculation program, correlated with the changes in the catalytic efficiency.
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19
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Manipulating the substrate specificity of murine dihydrofolate reductase enzyme using an expanded set of amino acids. Biochem Eng J 2015. [DOI: 10.1016/j.bej.2015.03.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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Ravikumar Y, Nadarajan SP, Yoo TH, Lee CS, Yun H. Unnatural amino acid mutagenesis-based enzyme engineering. Trends Biotechnol 2015; 33:462-70. [PMID: 26088007 DOI: 10.1016/j.tibtech.2015.05.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 05/07/2015] [Accepted: 05/13/2015] [Indexed: 02/09/2023]
Abstract
Traditional enzyme engineering relies on substituting one amino acid by one of the other 19 natural amino acids to change the functional properties of an enzyme. However, incorporation of unnatural amino acids (UAAs) has been harnessed to engineer efficient enzymes for biocatalysis. Residue-specific and site-specific in vivo incorporation methods are becoming the preferred approach for producing enzymes with altered or improved functions. We describe the contribution of in vivo UAA incorporation methodologies to enzyme engineering as well as the future prospects for the field, including the integration of UAAs with other new advances in enzyme engineering.
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Affiliation(s)
- Yuvaraj Ravikumar
- School of Biotechnology, Department of Biochemistry, Yeungnam University, Gyeongsan, Gyeongbuk 712-749, Korea
| | | | - Tae Hyeon Yoo
- Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea
| | - Chong-soon Lee
- School of Biotechnology, Department of Biochemistry, Yeungnam University, Gyeongsan, Gyeongbuk 712-749, Korea
| | - Hyungdon Yun
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Korea.
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21
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Temperature sensing using red fluorescent protein. BIOTECHNOL BIOPROC E 2015; 20:67-72. [PMID: 32218680 PMCID: PMC7090752 DOI: 10.1007/s12257-014-0456-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/18/2014] [Accepted: 09/26/2014] [Indexed: 01/17/2023]
Abstract
Genetically encoded fluorescent proteins are extensively utilized for labeling and imaging proteins, organelles, cell tissues, and whole organisms. In this study, we explored the feasibility of mRFP1 and its variants for measuring intracellular temperature. A linear relationship was observed between the temperature and fluorescence intensity of mRFP1 and its variants. Temperature sensitivities of E. coli expressing mRFP1, mRFP-P63A and mRFP-P63A[(4R)-FP] were -1.27%, -1.26% and -0.77%/°C, respectively. Finally, we demonstrated the potentiality of mRFP1 and its variants as an in vivo temperature sensor.
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22
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Currin A, Swainston N, Day PJ, Kell DB. Synthetic biology for the directed evolution of protein biocatalysts: navigating sequence space intelligently. Chem Soc Rev 2015; 44:1172-239. [PMID: 25503938 PMCID: PMC4349129 DOI: 10.1039/c4cs00351a] [Citation(s) in RCA: 251] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Indexed: 12/21/2022]
Abstract
The amino acid sequence of a protein affects both its structure and its function. Thus, the ability to modify the sequence, and hence the structure and activity, of individual proteins in a systematic way, opens up many opportunities, both scientifically and (as we focus on here) for exploitation in biocatalysis. Modern methods of synthetic biology, whereby increasingly large sequences of DNA can be synthesised de novo, allow an unprecedented ability to engineer proteins with novel functions. However, the number of possible proteins is far too large to test individually, so we need means for navigating the 'search space' of possible protein sequences efficiently and reliably in order to find desirable activities and other properties. Enzymologists distinguish binding (Kd) and catalytic (kcat) steps. In a similar way, judicious strategies have blended design (for binding, specificity and active site modelling) with the more empirical methods of classical directed evolution (DE) for improving kcat (where natural evolution rarely seeks the highest values), especially with regard to residues distant from the active site and where the functional linkages underpinning enzyme dynamics are both unknown and hard to predict. Epistasis (where the 'best' amino acid at one site depends on that or those at others) is a notable feature of directed evolution. The aim of this review is to highlight some of the approaches that are being developed to allow us to use directed evolution to improve enzyme properties, often dramatically. We note that directed evolution differs in a number of ways from natural evolution, including in particular the available mechanisms and the likely selection pressures. Thus, we stress the opportunities afforded by techniques that enable one to map sequence to (structure and) activity in silico, as an effective means of modelling and exploring protein landscapes. Because known landscapes may be assessed and reasoned about as a whole, simultaneously, this offers opportunities for protein improvement not readily available to natural evolution on rapid timescales. Intelligent landscape navigation, informed by sequence-activity relationships and coupled to the emerging methods of synthetic biology, offers scope for the development of novel biocatalysts that are both highly active and robust.
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Affiliation(s)
- Andrew Currin
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- School of Chemistry , The University of Manchester , Manchester M13 9PL , UK
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
| | - Neil Swainston
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
- School of Computer Science , The University of Manchester , Manchester M13 9PL , UK
| | - Philip J. Day
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
- Faculty of Medical and Human Sciences , The University of Manchester , Manchester M13 9PT , UK
| | - Douglas B. Kell
- Manchester Institute of Biotechnology , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK . ; http://dbkgroup.org/; @dbkell ; Tel: +44 (0)161 306 4492
- School of Chemistry , The University of Manchester , Manchester M13 9PL , UK
- Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM) , The University of Manchester , 131, Princess St , Manchester M1 7DN , UK
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23
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Odar C, Winkler M, Wiltschi B. Fluoro amino acids: A rarity in nature, yet a prospect for protein engineering. Biotechnol J 2015; 10:427-46. [DOI: 10.1002/biot.201400587] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 12/08/2014] [Accepted: 01/09/2015] [Indexed: 01/01/2023]
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24
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Lim SI, Mizuta Y, Takasu A, Kim YH, Kwon I. Site-specific bioconjugation of a murine dihydrofolate reductase enzyme by copper(I)-catalyzed azide-alkyne cycloaddition with retained activity. PLoS One 2014; 9:e98403. [PMID: 24887377 PMCID: PMC4041766 DOI: 10.1371/journal.pone.0098403] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 05/02/2014] [Indexed: 12/27/2022] Open
Abstract
Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is an efficient reaction linking an azido and an alkynyl group in the presence of copper catalyst. Incorporation of a non-natural amino acid (NAA) containing either an azido or an alkynyl group into a protein allows site-specific bioconjugation in mild conditions via CuAAC. Despite its great potential, bioconjugation of an enzyme has been hampered by several issues including low yield, poor solubility of a ligand, and protein structural/functional perturbation by CuAAC components. In the present study, we incorporated an alkyne-bearing NAA into an enzyme, murine dihydrofolate reductase (mDHFR), in high cell density cultivation of Escherichia coli, and performed CuAAC conjugation with fluorescent azide dyes to evaluate enzyme compatibility of various CuAAC conditions comprising combination of commercially available Cu(I)-chelating ligands and reductants. The condensed culture improves the protein yield 19-fold based on the same amount of non-natural amino acid, and the enzyme incubation under the optimized reaction condition did not lead to any activity loss but allowed a fast and high-yield bioconjugation. Using the established conditions, a biotin-azide spacer was efficiently conjugated to mDHFR with retained activity leading to the site-specific immobilization of the biotin-conjugated mDHFR on a streptavidin-coated plate. These results demonstrate that the combination of reactive non-natural amino acid incorporation and the optimized CuAAC can be used to bioconjugate enzymes with retained enzymatic activity.
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Affiliation(s)
- Sung In Lim
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia, United States of America
| | - Yukina Mizuta
- Department of Frontier Materials, Nagoya Institute of Technology, Nagoya, Aichi, Japan
| | - Akinori Takasu
- Department of Frontier Materials, Nagoya Institute of Technology, Nagoya, Aichi, Japan
| | - Yong Hwan Kim
- Department of Chemical Engineering, Kwangwoon University, Seoul, Republic of Korea
| | - Inchan Kwon
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia, United States of America
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
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25
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Deepankumar K, Shon M, Nadarajan SP, Shin G, Mathew S, Ayyadurai N, Kim BG, Choi SH, Lee SH, Yun H. Enhancing Thermostability and Organic Solvent Tolerance of ω-Transaminase through Global Incorporation of Fluorotyrosine. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201300706] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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26
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Lim SI, Mizuta Y, Takasu A, Hahn YS, Kim YH, Kwon I. Site-specific fatty acid-conjugation to prolong protein half-life in vivo. J Control Release 2013; 170:219-25. [PMID: 23735573 DOI: 10.1016/j.jconrel.2013.05.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 05/26/2013] [Indexed: 12/11/2022]
Abstract
Therapeutic proteins are indispensable in treating numerous human diseases. However, therapeutic proteins often suffer short serum half-life. In order to extend the serum half-life, a natural albumin ligand (a fatty acid) has been conjugated to small therapeutic peptides resulting in a prolonged serum half-life via binding to patients' serum albumin in vivo. However, fatty acid-conjugation has limited applicability due to lack of site-specificity resulting in the heterogeneity of conjugated proteins and a significant loss in pharmaceutical activity. In order to address these issues, we exploited the site-specific fatty acid-conjugation to a permissive site of a protein, using copper-catalyzed alkyne-azide cycloaddition, by linking a fatty acid derivative to p-ethynylphenylalanine incorporated into a protein using an engineered pair of yeast tRNA/aminoacyl tRNA synthetase. As a proof-of-concept, we show that single palmitic acid conjugated to superfolder green fluorescent protein (sfGFP) in a site-specific manner enhanced a protein's albumin-binding in vitro about 20 times and the serum half-life in vivo 5 times when compared to those of the unmodified sfGFP. Furthermore, the fatty acid conjugation did not cause a significant reduction in the fluorescence of sfGFP. Therefore, these results clearly indicate that the site-specific fatty acid-conjugation is a very promising strategy to prolong protein serum half-life in vivo without compromising its folded structure and activity.
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Affiliation(s)
- Sung In Lim
- Department of Chemical Engineering, University of Virginia, Charlottesville, VA 22904, USA
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27
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Zheng S, Kwon I. Controlling enzyme inhibition using an expanded set of genetically encoded amino acids. Biotechnol Bioeng 2013; 110:2361-70. [DOI: 10.1002/bit.24911] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Revised: 03/16/2013] [Accepted: 03/22/2013] [Indexed: 01/26/2023]
Affiliation(s)
- Shun Zheng
- Department of Chemical EngineeringUniversity of VirginiaCharlottesville, VA22904‐4741
| | - Inchan Kwon
- Department of Chemical EngineeringUniversity of VirginiaCharlottesville, VA22904‐4741
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28
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Kwon I, Lim SI. Non-Natural Amino Acids for Protein Engineering and New Protein Chemistries. MACROMOL CHEM PHYS 2013. [DOI: 10.1002/macp.201200710] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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Jungbauer A, Lee SY. Editorial: Breaking down the walls to achieve interdisciplinary science and engineering. Biotechnol J 2012; 7:4-5. [DOI: 10.1002/biot.201100484] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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