1
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Douglass J, Hsiue EHC, Mog BJ, Hwang MS, DiNapoli SR, Pearlman AH, Miller MS, Wright KM, Azurmendi PA, Wang Q, Paul S, Schaefer A, Skora AD, Molin MD, Konig MF, Liu Q, Watson E, Li Y, Murphy MB, Pardoll DM, Bettegowda C, Papadopoulos N, Gabelli SB, Kinzler KW, Vogelstein B, Zhou S. Bispecific antibodies targeting mutant RAS neoantigens. Sci Immunol 2021; 6:6/57/eabd5515. [PMID: 33649101 DOI: 10.1126/sciimmunol.abd5515] [Citation(s) in RCA: 100] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 02/01/2021] [Indexed: 12/18/2022]
Abstract
Mutations in the RAS oncogenes occur in multiple cancers, and ways to target these mutations has been the subject of intense research for decades. Most of these efforts are focused on conventional small-molecule drugs rather than antibody-based therapies because the RAS proteins are intracellular. Peptides derived from recurrent RAS mutations, G12V and Q61H/L/R, are presented on cancer cells in the context of two common human leukocyte antigen (HLA) alleles, HLA-A3 and HLA-A1, respectively. Using phage display, we isolated single-chain variable fragments (scFvs) specific for each of these mutant peptide-HLA complexes. The scFvs did not recognize the peptides derived from the wild-type form of RAS proteins or other related peptides. We then sought to develop an immunotherapeutic agent that was capable of killing cells presenting very low levels of these RAS-derived peptide-HLA complexes. Among many variations of bispecific antibodies tested, one particular format, the single-chain diabody (scDb), exhibited superior reactivity to cells expressing low levels of neoantigens. We converted the scFvs to this scDb format and demonstrated that they were capable of inducing T cell activation and killing of target cancer cells expressing endogenous levels of the mutant RAS proteins and cognate HLA alleles. CRISPR-mediated alterations of the HLA and RAS genes provided strong genetic evidence for the specificity of the scDbs. Thus, this approach could be applied to other common oncogenic mutations that are difficult to target by conventional means, allowing for more specific anticancer therapeutics.
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Affiliation(s)
- Jacqueline Douglass
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Emily Han-Chung Hsiue
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Brian J Mog
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Michael S Hwang
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Sarah R DiNapoli
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Alexander H Pearlman
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Michelle S Miller
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Bloomberg~Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21287, USA
| | - Katharine M Wright
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Bloomberg~Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21287, USA
| | - P Aitana Azurmendi
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Bloomberg~Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21287, USA
| | - Qing Wang
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. .,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Complete Omics Inc., Baltimore, MD 21227, USA
| | - Suman Paul
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Annika Schaefer
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Andrew D Skora
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Marco Dal Molin
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Department of Surgery, University of Maryland Medical Center, Baltimore, MD 21201, USA
| | - Maximilian F Konig
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Division of Rheumatology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
| | - Qiang Liu
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Evangeline Watson
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Yana Li
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | | | - Drew M Pardoll
- Bloomberg~Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21287, USA.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Chetan Bettegowda
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Department of Neurosurgery, Johns Hopkins University School of Medicine, MD 21205, USA
| | - Nickolas Papadopoulos
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Bloomberg~Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21287, USA.,Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Sandra B Gabelli
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kenneth W Kinzler
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Bloomberg~Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21287, USA
| | - Bert Vogelstein
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. .,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Bloomberg~Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21287, USA.,Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Shibin Zhou
- Ludwig Center, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. .,Lustgarten Pancreatic Cancer Research Laboratory, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.,Bloomberg~Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21287, USA
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2
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Suchsland R, Appel B, Virta P, Müller S. Synthesis of fully protected trinucleotide building blocks on a disulphide-linked soluble support. RSC Adv 2021; 11:3892-3896. [PMID: 35424330 PMCID: PMC8694130 DOI: 10.1039/d0ra10941j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 01/12/2021] [Indexed: 11/30/2022] Open
Abstract
In recent years, preparation of fully protected trinucleotide phosphoramidites as synthons for the codon-based synthesis of gene libraries as well as for the assembly of oligonucleotides from blockmers has gained much attention. We here describe the preparation of such trinucleotide synthons on a soluble support using a disulphide linker. Fully protected trinucleotides are synthesized on a tetrapodal soluble support using a disulphide linkage that upon reductive cleavage allows release of the trinucleotide with free 3′-OH group for further conversion to a phosphoramidite.![]()
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Affiliation(s)
- Ruth Suchsland
- University Greifswald
- Institute for Biochemistry
- 17487 Greifswald
- Germany
| | - Bettina Appel
- University Greifswald
- Institute for Biochemistry
- 17487 Greifswald
- Germany
| | - Pasi Virta
- University of Turku
- Department of Chemistry
- 20014 Turku
- Finland
| | - Sabine Müller
- University Greifswald
- Institute for Biochemistry
- 17487 Greifswald
- Germany
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3
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Almagro JC, Pedraza-Escalona M, Arrieta HI, Pérez-Tapia SM. Phage Display Libraries for Antibody Therapeutic Discovery and Development. Antibodies (Basel) 2019; 8:antib8030044. [PMID: 31544850 PMCID: PMC6784186 DOI: 10.3390/antib8030044] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/14/2019] [Accepted: 08/15/2019] [Indexed: 01/24/2023] Open
Abstract
Phage display technology has played a key role in the remarkable progress of discovering and optimizing antibodies for diverse applications, particularly antibody-based drugs. This technology was initially developed by George Smith in the mid-1980s and applied by John McCafferty and Gregory Winter to antibody engineering at the beginning of 1990s. Here, we compare nine phage display antibody libraries published in the last decade, which represent the state of the art in the discovery and development of therapeutic antibodies using phage display. We first discuss the quality of the libraries and the diverse types of antibody repertoires used as substrates to build the libraries, i.e., naïve, synthetic, and semisynthetic. Second, we review the performance of the libraries in terms of the number of positive clones per panning, hit rate, affinity, and developability of the selected antibodies. Finally, we highlight current opportunities and challenges pertaining to phage display platforms and related display technologies.
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Affiliation(s)
- Juan C Almagro
- GlobalBio, Inc., 320, Cambridge, MA 02138, USA.
- UDIBI, ENCB, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala S/N, Colonia Casco de Santo Tomas, Delegación Miguel Hidalgo, Ciudad de Mexico 11340, Mexico.
| | - Martha Pedraza-Escalona
- CONACyT-UDIBI, ENCB, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala S/N, Colonia Casco de Santo Tomas, Delegación Miguel Hidalgo, Ciudad de Mexico 11340, Mexico
| | - Hugo Iván Arrieta
- CONACyT-UDIBI, ENCB, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala S/N, Colonia Casco de Santo Tomas, Delegación Miguel Hidalgo, Ciudad de Mexico 11340, Mexico
| | - Sonia Mayra Pérez-Tapia
- CONACyT-UDIBI, ENCB, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala S/N, Colonia Casco de Santo Tomas, Delegación Miguel Hidalgo, Ciudad de Mexico 11340, Mexico
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4
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Valadon P, Pérez-Tapia SM, Nelson RS, Guzmán-Bringas OU, Arrieta-Oliva HI, Gómez-Castellano KM, Pohl MA, Almagro JC. ALTHEA Gold Libraries™: antibody libraries for therapeutic antibody discovery. MAbs 2019; 11:516-531. [PMID: 30663541 PMCID: PMC6512909 DOI: 10.1080/19420862.2019.1571879] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We describe here the design, construction and validation of ALTHEA Gold Libraries™. These single-chain variable fragment (scFv), semisynthetic libraries are built on synthetic human well-known IGHV and IGKV germline genes combined with natural human complementarity-determining region (CDR)-H3/JH (H3J) fragments. One IGHV gene provided a universal VH scaffold and was paired with two IGKV scaffolds to furnish different topographies for binding distinct epitopes. The scaffolds were diversified at positions identified as in contact with antigens in the known antigen-antibody complex structures. The diversification regime consisted of high-usage amino acids found at those positions in human antibody sequences. Functionality, stability and diversity of the libraries were improved throughout a three-step construction process. In a first step, fully synthetic primary libraries were generated by combining the diversified scaffolds with a set of synthetic neutral H3J germline gene fragments. The second step consisted of selecting the primary libraries for enhanced thermostability based on the natural capacity of Protein A to bind the universal VH scaffold. In the third and final step, the resultant stable synthetic antibody fragments were combined with natural H3J fragments obtained from peripheral blood mononuclear cells of a large pool of 200 donors. Validation of ALTHEA Gold Libraries™ with seven targets yielded specific antibodies in all the cases. Further characterization of the isolated antibodies indicated KD values as human IgG1 molecules in the single-digit and sub-nM range. The thermal stability (Tm) of all the antigen-binding fragments was 75°C–80°C, demonstrating that ALTHEA Gold Libraries™ are a valuable source of specific, high affinity and highly stable antibodies.
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Affiliation(s)
| | | | | | | | | | | | - Mary Ann Pohl
- c Tri-Institutional Therapeutics Discovery Institute , New York , NY , USA
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5
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Suchsland R, Appel B, Müller S. Synthesis of Trinucleotide Building Blocks in Solution and on Solid Phase. ACTA ACUST UNITED AC 2018; 75:e60. [PMID: 30375750 DOI: 10.1002/cpnc.60] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We have developed two methods, in solution and on solid phase, that give easy access to trinucleotide phosphoramidites capable of undergoing coupling reactions by the solid-phase phosphoramidite approach. The solution protocol is characterized by application of 5'-O-dimethoxytrityl (DMT) and 3'-O-tert-butyldimethylsilyl (TBDMS) as a pair of orthogonal protecting groups and 2-cyanoethyl (CE) for protection of the phosphate. Starting with suitably functionalized monomers, synthesis proceeds in the 3'- to 5'-direction, delivering the fully protected trinucleotide. The 3'-O-protecting group is cleaved followed by phosphitylation of the free 3'-OH group. The solid-phase protocol is based on standard phosphoramidite chemistry in conjunction with a dithiomethyl linkage connecting the 3'-starting nucleoside to the polymer. The disulfide bridge can be cleaved under neutral conditions for release of the trinucleotide from the support preserving all other protecting groups. © 2018 by John Wiley & Sons, Inc.
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Affiliation(s)
- Ruth Suchsland
- Institute for Biochemistry, University Greifswald, Greifswald, Germany
| | - Bettina Appel
- Institute for Biochemistry, University Greifswald, Greifswald, Germany
| | - Sabine Müller
- Institute for Biochemistry, University Greifswald, Greifswald, Germany
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6
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Suzuki T, Mochizuki Y, Kimura S, Akazawa-Ogawa Y, Hagihara Y, Nemoto N. Anti-survivin single-domain antibodies derived from an artificial library including three synthetic random regions by in vitro selection using cDNA display. Biochem Biophys Res Commun 2018; 503:2054-2060. [DOI: 10.1016/j.bbrc.2018.07.158] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 07/31/2018] [Indexed: 12/21/2022]
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7
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Suchsland R, Appel B, Müller S. Preparation of trinucleotide phosphoramidites as synthons for the synthesis of gene libraries. Beilstein J Org Chem 2018. [PMID: 29520304 PMCID: PMC5827815 DOI: 10.3762/bjoc.14.28] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The preparation of protein libraries is a key issue in protein engineering and biotechnology. Such libraries can be prepared by a variety of methods, starting from the respective gene library. The challenge in gene library preparation is to achieve controlled total or partial randomization at any predefined number and position of codons of a given gene, in order to obtain a library with a maximum number of potentially successful candidates. This purpose is best achieved by the usage of trinucleotide synthons for codon-based gene synthesis. We here review the strategies for the preparation of fully protected trinucleotides, emphasizing more recent developments for their synthesis on solid phase and on soluble polymers, and their use as synthons in standard DNA synthesis.
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Affiliation(s)
- Ruth Suchsland
- Institut für Biochemie, Ernst-Moritz-Arndt-Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany
| | - Bettina Appel
- Institut für Biochemie, Ernst-Moritz-Arndt-Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany
| | - Sabine Müller
- Institut für Biochemie, Ernst-Moritz-Arndt-Universität Greifswald, Felix-Hausdorff-Str. 4, D-17489 Greifswald, Germany
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8
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Lönnberg H. Synthesis of oligonucleotides on a soluble support. Beilstein J Org Chem 2017; 13:1368-1387. [PMID: 28781703 PMCID: PMC5530625 DOI: 10.3762/bjoc.13.134] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 06/19/2017] [Indexed: 12/23/2022] Open
Abstract
Oligonucleotides are usually prepared in lab scale on a solid support with the aid of a fully automated synthesizer. Scaling up of the equipment has allowed industrial synthesis up to kilogram scale. In spite of this, solution-phase synthesis has received continuous interest, on one hand as a technique that could enable synthesis of even larger amounts and, on the other hand, as a gram scale laboratory synthesis without any special equipment. The synthesis on a soluble support has been regarded as an approach that could combine the advantageous features of both the solution and solid-phase syntheses. The critical step of this approach is the separation of the support-anchored oligonucleotide chain from the monomeric building block and other small molecular reagents and byproducts after each coupling, oxidation and deprotection step. The techniques applied so far include precipitation, extraction, chromatography and nanofiltration. As regards coupling, all conventional chemistries, viz. phosphoramidite, H-phosphonate and phosphotriester strategies, have been attempted. While P(III)-based phosphoramidite and H-phosphonate chemistries are almost exclusively used on a solid support, the "outdated" P(V)-based phosphotriester chemistry still offers one major advantage for the synthesis on a soluble support; the omission of the oxidation step simplifies the coupling cycle. Several of protocols developed for the soluble-supported synthesis allow the preparation of both DNA and RNA oligomers of limited length in gram scale without any special equipment, being evidently of interest for research groups that need oligonucleotides in large amounts for research purposes. However, none of them has really tested at such a scale that the feasibility of their industrial use could be critically judged.
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Affiliation(s)
- Harri Lönnberg
- Department of Chemistry, University of Turku, FIN-20014 Turku, Finland
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9
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Matsuno Y, Shoji T, Kim S, Chiba K. Synthetic Method for Oligonucleotide Block by Using Alkyl-Chain-Soluble Support. Org Lett 2016; 18:800-3. [PMID: 26845521 DOI: 10.1021/acs.orglett.6b00077] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A straightforward method for the synthesis of oligonucleotide blocks using a Cbz-type alkyl-chain-soluble support (Z-ACSS) attached to the 3'-OH group of 3'-terminal nucleosides was developed. The Z-ACSS allowed for the preparation of fully protected deoxyribo- and ribo-oligonucleotides without chromatographic purification and released dimer- to tetramer-size oligonucleotide blocks via hydrogenation using a Pd/C catalyst without significant loss or migration of protective groups such as 5'-end 4,4'-dimethoxtrityl, 2-cyanoethyl on internucleotide bonds, or 2'-TBS.
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Affiliation(s)
- Yuki Matsuno
- Laboratory of Bio-organic Chemistry, Tokyo University of Agriculture and Technology , 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan
| | - Takao Shoji
- Laboratory of Bio-organic Chemistry, Tokyo University of Agriculture and Technology , 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan
| | - Shokaku Kim
- Laboratory of Bio-organic Chemistry, Tokyo University of Agriculture and Technology , 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan
| | - Kazuhiro Chiba
- Laboratory of Bio-organic Chemistry, Tokyo University of Agriculture and Technology , 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan
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10
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Kungurtsev V, Lönnberg H, Virta P. Synthesis of protected 2′-O-deoxyribonucleotides on a precipitative soluble support: a useful procedure for the preparation of trimer phosphoramidites. RSC Adv 2016. [DOI: 10.1039/c6ra22316h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
A straightforward procedure for the preparation of protected 2′-O-deoxyribonucleotide trimers, using the phosphotriester chemistry on a precipitative soluble support, was described.
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Affiliation(s)
- V. Kungurtsev
- Department of Chemistry
- University of Turku
- FI-20014 Turku
- Finland
| | - H. Lönnberg
- Department of Chemistry
- University of Turku
- FI-20014 Turku
- Finland
| | - P. Virta
- Department of Chemistry
- University of Turku
- FI-20014 Turku
- Finland
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11
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Fellouse F, Pal G. Methods for the Construction of Phage-Displayed Libraries. ACTA ACUST UNITED AC 2015. [DOI: 10.1201/b18196-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
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12
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Barreto K, Geyer CR. Screening combinatorial libraries of cyclic peptides using the yeast two-hybrid assay. Methods Mol Biol 2014; 1163:273-309. [PMID: 24841315 DOI: 10.1007/978-1-4939-0799-1_21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Peptides are useful reagents for reverse analysis of protein function in a variety of organisms, as they have a dominant mode of action that can inhibit protein interactions or activities. Further, peptides are important tools for validating proteins as therapeutic targets, for determining structure/activity relationships, and for designing small molecules. Genetic selection strategies have been developed for screening combinatorial peptide libraries to rapidly isolate peptides that interact with a given target. In genetic selections and biological assays, linear peptides are not very stable and are rapidly degraded. In contrast, cyclic peptides are more stable and bind with higher affinity. Genetic selections of cyclic peptides are difficult as they are not compatible with most selection technologies. Thus, there has been limited number of applications that use cyclic peptides for the reverse analysis of protein function.Here, we describe a protocol to isolate cyclic peptides that bind proteins in the yeast two-hybrid assay. Cyclic peptides used in the yeast two-hybrid assay are referred to as "lariat" peptides. Lariat peptides are made by blocking the intein-producing cyclic peptide reaction at an intermediate step. They consist of a lactone cyclic peptide or "noose" region connected by an amide bond to a transcription activation domain. Combinatorial libraries of >10(7) lariat peptides can be screened using the yeast two-hybrid assay to isolate lariat peptides for studying the function or validating the therapeutic potential of protein targets.
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Affiliation(s)
- Kris Barreto
- Department of Biochemistry, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, Canada, S7N 5E5
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13
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Arunachalam TS, Wichert C, Appel B, Müller S. Mixed oligonucleotides for random mutagenesis: best way of making them. Org Biomol Chem 2012; 10:4641-50. [PMID: 22552713 DOI: 10.1039/c2ob25328c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The generation of proteins, especially enzymes, with pre-deliberated, novel properties is a big challenge in the field of protein engineering. This aim, over the years was critically facilitated by newly emerging methods of combinatorial and evolutionary techniques, such as combinatorial gene synthesis followed by functional screening of many structural variants generated in parallel (library). Libraries can be generated by a large number of available methods. Therein the use of mixtures of pre-formed trinucleotide blocks representing codons for the 20 canonical amino acids for oligonucleotide synthesis stands out as allowing fully controlled partial (or total) randomization individually at any number of arbitrarily chosen codon positions of a given gene. This has created substantial demand of fully protected trinucleotide synthons of good reactivity in standard oligonucleotide synthesis. We here review methods for the preparation of oligonucleotide mixtures with a strong focus on codon-specific trinucleotide blocks.
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Affiliation(s)
- Tamil Selvi Arunachalam
- Institut für Biochemie, Ernst Moritz Arndt Universität, Felix Hausdorff Strasse 4, Greifswald, D-17487, Germany
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14
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Janczyk M, Appel B, Springstubbe D, Fritz HJ, Müller S. A new and convenient approach for the preparation of β-cyanoethyl protected trinucleotide phosphoramidites. Org Biomol Chem 2012; 10:1510-3. [PMID: 22231393 DOI: 10.1039/c2ob06934b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein we report a convenient approach for the preparation of fully protected trinucleotide synthons to be used for the synthesis of gene libraries. The trinucleotide synthons bear β-cyanoethyl groups at the phosphate residues, and thus can be used in standard oligonucleotide synthesis without additional steps for deprotection and work-up.
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Affiliation(s)
- Matthäus Janczyk
- Ernst-Moritz-Arndt-Universität Greifswald, Institut für Biochemie, Felix-Hausdorff-Str., 4, 17487 Greifswald, Germany
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15
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Garabedian M, Jarnik M, Kotova E, Tulin AV. Generating a knockdown transgene against Drosophila heterochromatic Tim17b gene encoding mitochondrial translocase subunit. PLoS One 2011; 6:e25945. [PMID: 21998726 PMCID: PMC3188573 DOI: 10.1371/journal.pone.0025945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 09/14/2011] [Indexed: 12/15/2022] Open
Abstract
Heterochromatic regions of eukaryotic genomes contain multiple functional elements involved in chromosomal dynamics, as well as multiple housekeeping genes. Cytological and molecular peculiarities of heterochromatic loci complicate genetic studies based on standard approaches developed using euchromatic genes. Here, we report the development of an RNAi-based knockdown transgenic construct and red fluorescent reporter transgene for a small gene, Tim17b, which localizes in constitutive heterochromatin of Drosophila melanogaster third chromosome and encodes a mitochondrial translocase subunit. We demonstrate that Tim17b protein is required strictly for protein delivery to mitochondrial matrix. Knockdown of Tim17b completely disrupts functions of the mitochondrial translocase complex. Using fluorescent recovery after photobleaching assay, we show that Tim17b protein has a very stable localization in the membranes of the mitochondrial network and that its exchange rate is close to zero when compared with soluble proteins of mitochondrial matrix. These results confirm that we have developed comprehensive tools to study functions of heterochromatic Tim17b gene.
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Affiliation(s)
- Mikael Garabedian
- Fox Chase Cancer Center, Philadelphia, Pennsylvania, United States of America
| | - Michael Jarnik
- Fox Chase Cancer Center, Philadelphia, Pennsylvania, United States of America
| | - Elena Kotova
- Fox Chase Cancer Center, Philadelphia, Pennsylvania, United States of America
| | - Alexei V. Tulin
- Fox Chase Cancer Center, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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16
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Nie L, Lavinder JJ, Sarkar M, Stephany K, Magliery TJ. Synthetic approach to stop-codon scanning mutagenesis. J Am Chem Soc 2011; 133:6177-86. [PMID: 21452871 DOI: 10.1021/ja106894g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A general combinatorial mutagenesis strategy using common dimethoxytrityl-protected mononucleotide phosphoramidites and a single orthogonally protected trinucleotide phosphoramidite (Fmoc-TAG; Fmoc = 9-fluorenylmethoxycarbonyl) was developed to scan a gene with the TAG amber stop codon with complete synthetic control. In combination with stop-codon suppressors that insert natural (e.g., alanine) or unnatural (e.g., p-benzoylphenylalanine, Bpa) amino acids, a single DNA library can be used to incorporate different amino acids for diverse purposes. Here, we scanned TAG codons through part of the gene for a model four-helix bundle protein, Rop, which regulates the copy number of ColE1 plasmids. Alanine was incorporated into Rop for mapping its binding site using an in vivo activity screen, and subtle but important differences from in vitro gel-shift studies of Rop function are evident. As a test, Bpa was incorporated using a Phe14 amber mutant isolated from the scanning library. Surprisingly, Phe14Bpa-Rop is weakly active, despite the critical role of Phe14 in Rop activity. Bpa is a photoaffinity label unnatural amino acid that can form covalent bonds with adjacent molecules upon UV irradiation. Irradiation of Phe14Bpa-Rop, which is a dimer in solution like wild-type Rop, results in covalent dimers, trimers, and tetramers. This suggests that Phe14Bpa-Rop weakly associates as a tetramer in solution and highlights the use of Bpa cross-linking as a means of trapping weak and transient interactions.
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Affiliation(s)
- Lihua Nie
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA
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17
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Baum PD, Young JJ, Zhang Q, Kasakow Z, McCune JM. Design, construction, and validation of a modular library of sequence diversity standards for polymerase chain reaction. Anal Biochem 2010; 411:106-15. [PMID: 21111699 DOI: 10.1016/j.ab.2010.11.035] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 11/13/2010] [Accepted: 11/17/2010] [Indexed: 12/29/2022]
Abstract
Methods to measure the sequence diversity of polymerase chain reaction (PCR)-amplified DNA lack standards for use as assay calibrators and controls. Here we present a general and economical method for developing customizable DNA standards of known sequence diversity. Standards ranging from 1 to 25,000 sequences were generated by directional ligation of oligonucleotide "words" of standard length and GC content and then amplified by PCR. The sequence accuracy and diversity of the library were validated using AmpliCot analysis (DNA hybridization kinetics) and Illumina sequencing. The library has the following features: (i) pools containing tens of thousands of sequences can be generated from the ligation of relatively few commercially synthesized short oligonucleotides; (ii) each sequence differs from all others in the library at a minimum of three nucleotide positions, permitting discrimination between different sequences by either sequencing or hybridization; (iii) all sequences have identical length, GC content, and melting temperature; (iv) the identity of each standard can be verified by restriction digestion; and (v) once made, the ends of the library may be cleaved and replaced with sequences to match any PCR primer pair. These standards should greatly improve the accuracy and reproducibility of sequence diversity measurements.
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Affiliation(s)
- Paul D Baum
- University of California, San Francisco, CA 94143, USA.
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18
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Jackrel ME, Cortajarena AL, Liu TY, Regan L. Screening libraries to identify proteins with desired binding activities using a split-GFP reassembly assay. ACS Chem Biol 2010; 5:553-62. [PMID: 20038141 DOI: 10.1021/cb900272j] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Designer protein modules, which bind specifically to a desired target, have numerous potential applications. One approach to creating such proteins is to construct and screen libraries. Here we present a detailed description of using a split-GFP reassembly assay to screen libraries and identify proteins with novel binding properties. Attractive features of the split-GFP based screen are the absence of false positives and the simplicity, robustness, and ease of automation of the screen. Here, we describe both the construction of a naive protein library, and screening of the library using the split-GFP assay to identify proteins that bind specifically to chosen peptide sequences.
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Affiliation(s)
| | | | - Tina Y. Liu
- Molecular Biophysics & Biochemistry, Yale University, New Haven, Connecticut 06520
| | - Lynne Regan
- Departments of Chemistry
- Molecular Biophysics & Biochemistry, Yale University, New Haven, Connecticut 06520
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19
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Lee SC. Implications of available design space for identification of non-immunogenic protein therapeutics. Biomed Microdevices 2009; 12:283-6. [PMID: 20012559 DOI: 10.1007/s10544-009-9383-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Immunogenicity/antibody responses are major issues for parenteral proteins and nanotherapeutics (nanovectors, diagnostics, theranostics, etc.), and robust antibody responses require T-helper epitopes. T-helper epitopes consist of specific amino acids at specific positions (anchor positions) in immunogens which contact the major histocompatibility complex (MHC), provide most of the energy for MHC binding and constitute the binding motif for the corresponding MHC alleles. We developed an algorithm that considers motifs to design vaccines lacking unwanted T-cell epitopes, and found numbers of such vaccines can be astronomical (Lee et al. 2009). The algorithm can be used to design reduced immunogenicity proteins, and numbers of predicted proteins are also immense. Reducing T-helper epitope content reduces protein immunogenicity, but the depth of mutagensis needed to eliminate immunogenicity is commonly assumed to be too great for retention of protein bioactivity. However, very deep, but successful substitution, insertion and deletion mutagenesis have been reported. These reports and design space the algorithm reveals suggest development of non-immunogenic therapeutics might be more feasible than commonly assumed.
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Affiliation(s)
- Stephen Craig Lee
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, USA.
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20
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Beaucage SL, Caruthers MH. Synthetic strategies and parameters involved in the synthesis of oligodeoxyribonucleotides according to the phosphoramidite method. ACTA ACUST UNITED AC 2008; Chapter 3:Unit 3.3. [PMID: 18428844 DOI: 10.1002/0471142700.nc0303s00] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The phosphoramidite approach has had a major impact on the synthesis of oligonucleotides. This unit describes parameters that affect the performance of this method for preparing oligodeoxyribonucleotides, as well as a number of compatible strategies. Milestones that led to the discovery of the approach are chronologically reported. Alternate strategies are also described to underscore the versatility by which these synthons can be obtained. Mechanisms of deoxyribonucleoside phosphoramidite activation, factors affecting condensation, and deprotection strategies are discussed.
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Affiliation(s)
- S L Beaucage
- Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland, USA
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21
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Yagodkin A, Azhayev A, Roivainen J, Antopolsky M, Kayushin A, Korosteleva M, Miroshnikov A, Randolph J, Mackie H. Improved synthesis of trinucleotide phosphoramidites and generation of randomized oligonucleotide libraries. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2007; 26:473-97. [PMID: 17578745 DOI: 10.1080/15257770701426260] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A new method to produce a set of 20 high quality trinucleotide phosphoramidites on a 5-10 g scale each was developed. The procedure starts with condensation reactions of P-components with N-acyl nucleosides, bearing the 3 '-hydroxyl function protected with 2-azidomethylbenzoyl, to give fully protected dinucleoside phosphates 13. Upon cleavage of dimethoxytrityl group from 13, dinucleoside phosphates 16 are initially transformed into trinucleoside diphosphates 19 and then the 2-azidomethylbenzoyl is selectively removed under neutral conditions to generate trinucleoside diphosphates 5 in excellent yield. Subsequent 3 '-phosphitylation affords target trinucleotide phosphoramidites 7. When mutagenic oligonucleotides are synthesized employing mixtures of building blocks 7 as well as following the new synthetic protocol, representative oligonucleotide libraries are generated in good yields.
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Affiliation(s)
- Andrey Yagodkin
- Department of Pharmaceutical Chemistry, University of Kuopio, Kuopio, Finland and Metkinen Chemistry, Kuopio, Finland
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22
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Osuna J, Yáñez J, Soberón X, Gaytán P. Protein evolution by codon-based random deletions. Nucleic Acids Res 2004; 32:e136. [PMID: 15459282 PMCID: PMC521680 DOI: 10.1093/nar/gnh135] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2004] [Revised: 09/10/2004] [Accepted: 09/15/2004] [Indexed: 11/14/2022] Open
Abstract
A method to delete in-phase codons throughout a defined target region of a gene has been developed. This approach, named the codon-based random deletion (COBARDE) method, is able to delete complete codons in a random and combinatorial mode. Robustness, automation and fine-tuning of the mutagenesis rate are essential characteristics of the method, which is based on the assembly of oligonucleotides and on the use of two transient orthogonal protecting groups during the chemical synthesis. The performance of the method for protein function evolution was demonstrated by changing the substrate specificity of TEM-1 beta-lactamase. Functional ceftazidime-resistant beta-lactamase variants containing several deleted residues inside the catalytically important omega-loop region were found. The results show that the COBARDE method is a useful new molecular tool to access previously unexplorable sequence space.
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Affiliation(s)
- Joel Osuna
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología/UNAM, Ap. Postal 510-3 Cuernavaca, Morelos 62250, México
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23
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Tabuchi I, Soramoto S, Ueno S, Husimi Y. Multi-line split DNA synthesis: a novel combinatorial method to make high quality peptide libraries. BMC Biotechnol 2004; 4:19. [PMID: 15341664 PMCID: PMC520752 DOI: 10.1186/1472-6750-4-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2004] [Accepted: 09/01/2004] [Indexed: 11/30/2022] Open
Abstract
Background We developed a method to make a various high quality random peptide libraries for evolutionary protein engineering based on a combinatorial DNA synthesis. Results A split synthesis in codon units was performed with mixtures of bases optimally designed by using a Genetic Algorithm program. It required only standard DNA synthetic reagents and standard DNA synthesizers in three lines. This multi-line split DNA synthesis (MLSDS) is simply realized by adding a mix-and-split process to normal DNA synthesis protocol. Superiority of MLSDS method over other methods was shown. We demonstrated the synthesis of oligonucleotide libraries with 1016 diversity, and the construction of a library with random sequence coding 120 amino acids containing few stop codons. Conclusions Owing to the flexibility of the MLSDS method, it will be able to design various "rational" libraries by using bioinformatics databases.
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Affiliation(s)
- Ichiro Tabuchi
- Tokyo Evolution Research Center, 1-1-45-504, Okubo, Shinjuku-ku, Tokyo 169-0072, Japan
- Department of Functional Materials Science, Saitama University,255 Shimo-Okubo, Saitama 338-8570, Japan
| | - Sayaka Soramoto
- Department of Functional Materials Science, Saitama University,255 Shimo-Okubo, Saitama 338-8570, Japan
| | - Shingo Ueno
- Department of Functional Materials Science, Saitama University,255 Shimo-Okubo, Saitama 338-8570, Japan
| | - Yuzuru Husimi
- Department of Functional Materials Science, Saitama University,255 Shimo-Okubo, Saitama 338-8570, Japan
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24
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Abstract
Why do proteins adopt the conformations that they do, and what determines their stabilities? While we have come to some understanding of the forces that underlie protein architecture, a precise, predictive, physicochemical explanation is still elusive. Two obstacles to addressing these questions are the unfathomable vastness of protein sequence space, and the difficulty in making direct physical measurements on large numbers of protein variants. Here, we review combinatorial methods that have been applied to problems in protein biophysics over the last 15 years. The effects of hydrophobic core composition, the most important determinant of structure and stability, are still poorly understood. Particular attention is given to core composition as addressed by library methods. Increasingly useful screens and selections, in combination with modern high-throughput approaches borrowed from genomics and proteomics efforts, are making the empirical, statistical correlation between sequence and structure a tractable problem for the coming years.
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Affiliation(s)
- Thomas J Magliery
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT, USA
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25
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Chang CY, Norris JD, Jansen M, Huang HJ, McDonnell DP. Application of random peptide phage display to the study of nuclear hormone receptors. Methods Enzymol 2003; 364:118-42. [PMID: 14631842 DOI: 10.1016/s0076-6879(03)64007-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Ching-yi Chang
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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26
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Gaytán P, Osuna J, Soberón X. Novel ceftazidime-resistance beta-lactamases generated by a codon-based mutagenesis method and selection. Nucleic Acids Res 2002; 30:e84. [PMID: 12177312 PMCID: PMC134257 DOI: 10.1093/nar/gnf083] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Four known and nine new ceftazidime-resistance beta-lactamases were generated by a novel, contaminating codon-based mutagenesis approach. In this method, wild-type codons are spiked with a set of mutant codons during oligonucleotide synthesis, generating random combinatorial libraries of primers that contain few codon replacements per variant. Mutant codons are assembled by tandem addition of a diluted mixture of five Fmoc-dimer amidites to the growing oligo and a mixture of four DMTr-monomer amidites to generate 20 trinucleotides that encode a set of 18 amino acids. Wild-type codons are assembled with conventional chemistry and the whole process takes place in only one synthesis column, making its automation feasible. The random and binomial behavior of this approach was tested in the polylinker region of plasmid pUC19 by the synthesis of three oligonucleotide libraries mutagenized at different rates and cloned as mutagenic cassettes. Additionally, the method was biologically assessed by mutating six contiguous codons that encode amino acids 237-243 (ABL numbering) of the TEM(pUC19) beta-lactamase, which is functionally equivalent to the clinically important TEM-1 beta-lactamase. The best ceftazidime-recognizing variant was a triple mutant, R164H:E240K: R241A, displaying a 333-fold higher resistance than the wild-type enzyme.
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Affiliation(s)
- Paul Gaytán
- Instituto de Biotecnología/UNAM, Ap. Postal 510-3, Cuernavaca, Morelos 62250, México.
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27
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Pon RT, Yu S, Sanghvi YS. Tandem oligonucleotide synthesis on solid-phase supports for the production of multiple oligonucleotides. J Org Chem 2002; 67:856-64. [PMID: 11856029 DOI: 10.1021/jo0160773] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
More than one oligonucleotide can be synthesized at a time by linking multiple oligonucleotides end-to-end in a tandem manner on the surface of a solid-phase support. The 5'-terminal hydroxyl position of one oligonucleotide serves as the starting point for the next oligonucleotide synthesis. The two oligonucleotides are linked via a cleavable 3'-O-hydroquinone-O,O'-diacetic acid linker arm (Q-linker). The Q-linker is rapidly and efficiently coupled to the 5'-OH position of immobilized oligonucleotides using HATU, HBTU, or HCTU in the presence of 1 equiv of DMAP. This protocol avoids introduction of phosphate linkages on either the 3'- or 5'-end of oligonucleotides. A single NH(4)OH cleavage step can simultaneously release the products from the surface of the support and each other to produce free 5'- and 3'-hydroxyl termini. Selective cleavage of one oligonucleotide out of two sequences has also been accomplished via a combination of succinyl and Q-linker linker arms. Tandem synthesis of multiple oligonucleotides is useful for producing sets of primers for PCR, DNA sequencing, and other diagnostic applications as well as double-stranded oligonucleotides. Tandem synthesis of the same sequence multiple times increases the yield of material from any single synthesis column for maximum economy in large-scale synthesis. This method can also be combined with reusable solid-phase supports to further reduce the cost of oligonucleotide production.
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Affiliation(s)
- Richard T Pon
- Department of Biochemistry and Molecular Biology, University of Calgary, 3350 Hospital Dr. N.W., Calgary, Alberta, Canada T2N 4N1.
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28
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Murakami H, Hohsaka T, Sisido M. Random insertion and deletion of arbitrary number of bases for codon-based random mutation of DNAs. Nat Biotechnol 2002; 20:76-81. [PMID: 11753366 DOI: 10.1038/nbt0102-76] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A general method was developed for the construction of a library of mutant genes. The method, termed random insertion/deletion (RID) mutagenesis, enables deletion of an arbitrary number of consecutive bases at random positions and, at the same time, insertion of a specific sequence or random sequences of an arbitrary number into the same position. The applicability of the RID mutagenesis was demonstrated by replacing three randomly selected consecutive bases by the BglII recognition sequence (AGATCT) in the GFPUV gene. In addition, the randomly selected three bases were replaced by a mixture of 20 codons. These mutants were expressed in Escherichia coli, and those that showed fluorescence properties different from the wild-type GFP were selected. A yellow fluorescent protein and an enhanced green fluorescent protein, neither of which could be obtained by error-prone PCR mutagenesis, were found among the six mutants selected. Several mutants of the DsRed protein that show different fluorescence properties were also obtained.
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Affiliation(s)
- Hiroshi Murakami
- Department of Bioscience and Biotechnology, Faculty of Engineering, Okayama University, 3-1-1 Tsushimanaka, Okayama 700-8530, Japan
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29
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Gaytán P, Yáñez J, Sánchez F, Soberón X. Orthogonal combinatorial mutagenesis: a codon-level combinatorial mutagenesis method useful for low multiplicity and amino acid-scanning protocols. Nucleic Acids Res 2001; 29:E9. [PMID: 11160911 PMCID: PMC30410 DOI: 10.1093/nar/29.3.e9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We describe here a method to generate combinatorial libraries of oligonucleotides mutated at the codon-level, with control of the mutagenesis rate so as to create predictable binomial distributions of mutants. The method allows enrichment of the libraries with single, double or larger multiplicity of amino acid replacements by appropriate choice of the mutagenesis rate, depending on the concentration of synthetic precursors. The method makes use of two sets of deoxynucleoside-phosphoramidites bearing orthogonal protecting groups [4,4'-dimethoxytrityl (DMT) and 9-fluorenylmethoxycarbonyl (Fmoc)] in the 5' hydroxyl. These phosphoramidites are divergently combined during automated synthesis in such a way that wild-type codons are assembled with commercial DMT-deoxynucleoside-methyl-phosphoramidites while mutant codons are assembled with Fmoc-deoxynucleoside-methyl-phosphoramidites in an NNG/C fashion in a single synthesis column. This method is easily automated and suitable for low mutagenesis rates and large windows, such as those required for directed evolution and alanine scanning. Through the assembly of three oligonucleotide libraries at different mutagenesis rates, followed by cloning at the polylinker region of plasmid pUC18 and sequencing of 129 clones, we concluded that the method performs essentially as intended.
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Affiliation(s)
- P Gaytán
- Unidad de Síntesis and Departamento de Reconocimiento Molecular y Bioestructura, Instituto de Biotecnología/UNAM Ap. Postal 510-3 Cuernavaca, Morelos 62250, México
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30
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Knappik A, Ge L, Honegger A, Pack P, Fischer M, Wellnhofer G, Hoess A, Wölle J, Plückthun A, Virnekäs B. Fully synthetic human combinatorial antibody libraries (HuCAL) based on modular consensus frameworks and CDRs randomized with trinucleotides. J Mol Biol 2000; 296:57-86. [PMID: 10656818 DOI: 10.1006/jmbi.1999.3444] [Citation(s) in RCA: 505] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
By analyzing the human antibody repertoire in terms of structure, amino acid sequence diversity and germline usage, we found that seven V(H) and seven V(L) (four Vkappa and three Vlambda) germline families cover more than 95 % of the human antibody diversity used. A consensus sequence was derived for each family and optimized for expression in Escherichia coli. In order to make all six complementarity determining regions (CDRs) accessible for diversification, the synthetic genes were designed to be modular and mutually compatible by introducing unique restriction endonuclease sites flanking the CDRs. Molecular modeling verified that all canonical classes were present. We could show that all master genes are expressed as soluble proteins in the periplasm of E. coli. A first set of antibody phage display libraries totalling 2x10(9) members was created after cloning the genes in all 49 combinations into a phagemid vector, itself devoid of the restriction sites in question. Diversity was created by replacing the V(H) and V(L) CDR3 regions of the master genes by CDR3 library cassettes, generated from mixed trinucleotides and biased towards natural human antibody CDR3 sequences. The sequencing of 257 members of the unselected libraries indicated that the frequency of correct and thus potentially functional sequences was 61 %. Selection experiments against many antigens yielded a diverse set of binders with high affinities. Due to the modular design of all master genes, either single binders or even pools of binders can now be rapidly optimized without knowledge of the particular sequence, using pre-built CDR cassette libraries. The small number of 49 master genes will allow future improvements to be incorporated quickly, and the separation of the frameworks may help in analyzing why nature has evolved these distinct subfamilies of antibody germline genes.
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Affiliation(s)
- A Knappik
- MorphoSys AG, Lena-Christ-Str. 48, Martinsried/Munich, 82152, Germany.
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31
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Neuner P, Cortese R, Monaci P. Codon-based mutagenesis using dimer-phosphoramidites. Nucleic Acids Res 1998; 26:1223-7. [PMID: 9469829 PMCID: PMC147399 DOI: 10.1093/nar/26.5.1223] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
A new approach for the synthesis of randomized DNA sequences containing the 20 codons corresponding to all natural amino acids is described. The strategy is based on the use of dinucleotide phosphoramidite building blocks within a resin-splitting procedure. Through this protocol, a minimal number of seven dimers is sufficient to encode all 20 natural amino acids. This synthesis procedure is extremely flexible and allows codon usage from different hosts to be accommodated.
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Affiliation(s)
- P Neuner
- Chemistry Department, Istituto di Ricerche di Biologia Molecolare P. Angeletti, Via Pontina km 30.600, 00040 Pomezia (Roma), Italy.
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32
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Jensen LJ, Andersen KV, Svendsen A, Kretzschmar T. Scoring functions for computational algorithms applicable to the design of spiked oligonucleotides. Nucleic Acids Res 1998; 26:697-702. [PMID: 9443959 PMCID: PMC147326 DOI: 10.1093/nar/26.3.697] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Protein engineering by inserting stretches of random DNA sequences into target genes in combination with adequate screening or selection methods is a versatile technique to elucidate and improve protein functions. Established compounds for generating semi-random DNA sequences are spiked oligonucleotides which are synthesised by interspersing wild type (wt) nucleotides of the target sequence with certain amounts of other nucleotides. Directed spiking strategies reduce the complexity of a library to a manageable format compared with completely random libraries. Computational algorithms render feasible the calculation of appropriate nucleotide mixtures to encode specified amino acid subpopulations. The crucial element in the ranking of spiked codons generated during an iterative algorithm is the scoring function. In this report three scoring functions are analysed: the sum-of-square-differences function s, a modified cubic function c, and a scoring function m derived from maximum likelihood considerations. The impact of these scoring functions on calculated amino acid distributions is demonstrated by an example of mutagenising a domain surrounding the active site serine of subtilisin-like proteases. At default weight settings of one for each amino acid, the new scoring function m is superior to functions s and c in finding matches to a given amino acid population.
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Affiliation(s)
- L J Jensen
- Department of Enzyme Design, Novo Nordisk A/S, DK-2880 Bagsvaerd, Denmark
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33
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Tomandl D, Schober A, Schwienhorst A. Optimizing doped libraries by using genetic algorithms. J Comput Aided Mol Des 1997; 11:29-38. [PMID: 9139109 DOI: 10.1023/a:1008071310472] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The insertion of random sequences into protein-encoding genes in combination with biological selection techniques has become a valuable tool in the design of molecules that have useful and possibly novel properties. By employing highly effective screening protocols, a functional and unique structure that had not been anticipated can be distinguished among a huge collection of inactive molecules that together represent all possible amino acid combinations. This technique is severely limited by its restriction to a library of manageable size. One approach for limiting the size of a mutant library relies on 'doping schemes', where subsets of amino acids are generated that reveal only certain combinations of amino acids in a protein sequence. Three mononucleotide mixtures for each codon concerned must be designed, such that the resulting codons that are assembled during chemical gene synthesis represent the desired amino acid mixture on the level of the translated protein. In this paper we present a doping algorithm that "reverse translates' a desired mixture of certain amino acids into three mixtures of mononucleotides. The algorithm is designed to optimally bias these mixtures towards the codons of choice. This approach combines a genetic algorithm with local optimization strategies based on the downhill simplex method. Disparate relative representations of all amino acids (and stop codons) within a target set can be generated. Optional weighing factors are employed to emphasize the frequencies of certain amino acids and their codon usage, and to compensate for reaction rates of different mononucleotide building blocks (synthons) during chemical DNA synthesis. The effect of statistical errors that accompany an experimental realization of calculated nucleotide mixtures on the generated mixtures of amino acids is simulated. These simulations show that the robustness of different optima with respect to small deviations from calculated values depends on their concomitant fitness. Furthermore, the calculations probe the fitness landscape locally and allow a preliminary assessment of its structure.
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Affiliation(s)
- D Tomandl
- Department of Molecular Evolution Biology, Institute for Molecular Biotechnology, Jena, Germany
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Loeb LA. Unnatural nucleotide sequences in biopharmaceutics. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 1996; 35:321-47. [PMID: 8920210 DOI: 10.1016/s1054-3589(08)60280-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- L A Loeb
- Department of Pathology, University of Washington School of Medicine, Seattle 98195, USA
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35
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Ono A, Matsuda A, Zhao J, Santi DV. The synthesis of blocked triplet-phosphoramidites and their use in mutagenesis. Nucleic Acids Res 1995; 23:4677-82. [PMID: 8524660 PMCID: PMC307443 DOI: 10.1093/nar/23.22.4677] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
A general approach for the synthesis of oligonucleotide-triplet phosphoramidites and the synthesis of four such blocks are described. A strategy was devised to minimize the number of dimer precursors needed for synthesis of a complete set of triplet-amidite blocks encoding all 20 amino acids. Whereas synthesis of 20 triplet-amidite blocks consisting of codon sequences requires 16 dimer blocks, just seven dimer blocks are required to synthesize all required antisense sequences. The antisense sequences are then converted to codons in template mediated replication. Using a mixture of four triplet-amidites and conventional automated solid-phase DNA synthesis, short (6mer) and medium length (30mer) oligonucleotide mixtures were synthesized and analyzed. The latter was replicated in vitro and used as a mutagenic cassette to produce four mutants of Asp 221 in the enzyme thymidylate synthase. The method establishes the direction and utility for the production and use of triplet-amidite blocks in DNA synthesis.
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Affiliation(s)
- A Ono
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
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36
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Abstract
Most attempts to engineer the properties of proteins have employed single or multiple substitution mutations, which typically produce minor changes in structure. Recent structural and stability studies of insertion and deletion mutants clearly indicate that relatively large structural perturbations can be induced by altering the spacing of residues along the polypeptide backbone, often without major losses in protein stability. Although their effects are difficult to anticipate, insertions and deletions provide important new tools for altering protein structures in directions not achievable with substitutions alone.
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Affiliation(s)
- D Shortle
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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37
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Kay BK. Biologically displayed random peptides as reagents in mapping protein-protein interactions. ACTA ACUST UNITED AC 1995. [DOI: 10.1007/bf02172066] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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38
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Virnekäs B, Ge L, Plückthun A, Schneider KC, Wellnhofer G, Moroney SE. Trinucleotide phosphoramidites: ideal reagents for the synthesis of mixed oligonucleotides for random mutagenesis. Nucleic Acids Res 1994; 22:5600-7. [PMID: 7838712 PMCID: PMC310122 DOI: 10.1093/nar/22.25.5600] [Citation(s) in RCA: 173] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Trinucleotide phosphoramidites representing codons for all 20 amino acids have been prepared and used in automated, solid-phase DNA synthesis. In contrast to an earlier report, we show that these substances can be used to introduce entire codons into oligonucleotides in excess of 98% yield, and are ideal reagents for the synthesis of mixed oligonucleotides for random mutagenesis.
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39
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Osuna J, Flores H, Soberón X. Microbial systems and directed evolution of protein activities. Crit Rev Microbiol 1994; 20:107-16. [PMID: 8080624 DOI: 10.3109/10408419409113550] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Recent advances in recombinant DNA methodology have had an important impact on the capacity to manipulate protein-coding sequences. The appearance of new, powerful screening systems completes a scenario for conducting directed evolution experiments. We review here some of the latest developments in experimental approaches to directed evolution, utilizing microbial systems. These include phage display, surface display, operator-repressor systems, and novel mutagenesis approaches. We also highlight the achievements and limitations of current methodologies. We present strategies used by our own group that permitted isolation of specificity mutants of beta-lactamase. Possible improvements for the future of the variation-selection approach to the study and manipulation of proteins are presented.
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Affiliation(s)
- J Osuna
- Department of Molecular Biology, Instituto de Biotecnología-UNAM
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40
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Gregoret LM, Sauer RT. Additivity of mutant effects assessed by binomial mutagenesis. Proc Natl Acad Sci U S A 1993; 90:4246-50. [PMID: 8483940 PMCID: PMC46483 DOI: 10.1073/pnas.90.9.4246] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Eleven amino acid positions in the helix-turn-helix of lambda repressor have been mutagenized by using a combinatorial method in which alanine is substituted at each position with a probability of 0.5. Approximately 25% of the 2048 proteins in the resulting binomial library are active, including some variants with as many as seven alanine substitutions. The frequency of alanine substitutions in the set of active variants is a measure of the importance of the wild-type residue at each mutagenized position, and comparison of the frequencies of pairwise mutations with those expected based upon the single-position frequencies allows the additivity of mutant effects to be tested. For the positions examined here, we find that the effects of multiple substitutions are largely additive and are able to predict the activity class of the binomial mutants with 90% accuracy by using a model that simply sums penalty scores derived from the alanine substitution frequencies. We also find, however, that several residue pairs, including some that are distant in the three-dimensional structure, do display nonadditive effects that appear to be statistically significant.
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Affiliation(s)
- L M Gregoret
- Department of Biology, Massachusetts Institute of Technology, Cambridge 02139
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Keefe LJ, Sondek J, Shortle D, Lattman EE. The alpha aneurism: a structural motif revealed in an insertion mutant of staphylococcal nuclease. Proc Natl Acad Sci U S A 1993; 90:3275-9. [PMID: 8475069 PMCID: PMC46282 DOI: 10.1073/pnas.90.8.3275] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The x-ray crystal structure of a mutant of staphylococcal nuclease that contains a single glycine residue inserted in the C-terminal alpha-helix has been solved to 1.67 A resolution and refined to a crystallographic R value of 0.170. This inserted glycine residue is accommodated in the alpha-helix by formation of a previously uncharacterized bulge, which we term the alpha aneurism. A conformational search of known protein structures has identified the alpha aneurism in a number of protein families, including the histocompatibility antigens and hemoglobins.
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Affiliation(s)
- L J Keefe
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205-2185
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