1
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Schofield P, Taylor AI, Rihon J, Peña Martinez CD, Zinn S, Mattelaer CA, Jackson J, Dhaliwal G, Schepers G, Herdewijn P, Lescrinier E, Christ D, Holliger P. Characterization of an HNA aptamer suggests a non-canonical G-quadruplex motif. Nucleic Acids Res 2023; 51:7736-7748. [PMID: 37439359 PMCID: PMC10450178 DOI: 10.1093/nar/gkad592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/09/2023] [Accepted: 07/05/2023] [Indexed: 07/14/2023] Open
Abstract
Nucleic acids not only form the basis of heredity, but are increasingly a source of novel nano-structures, -devices and drugs. This has spurred the development of chemically modified alternatives (xeno nucleic acids (XNAs)) comprising chemical configurations not found in nature to extend their chemical and functional scope. XNAs can be evolved into ligands (XNA aptamers) that bind their targets with high affinity and specificity. However, detailed investigations into structural and functional aspects of XNA aptamers have been limited. Here we describe a detailed structure-function analysis of LYS-S8-19, a 1',5'-anhydrohexitol nucleic acid (HNA) aptamer to hen egg-white lysozyme (HEL). Mapping of the aptamer interaction interface with its cognate HEL target antigen revealed interaction epitopes, affinities, kinetics and hot-spots of binding energy similar to protein ligands such as anti-HEL-nanobodies. Truncation analysis and molecular dynamics (MD) simulations suggest that the HNA aptamer core motif folds into a novel and not previously observed HNA tertiary structure, comprising non-canonical hT-hA-hT/hT-hT-hT triplet and hG4-quadruplex structures, consistent with its recognition by two different G4-specific antibodies.
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Affiliation(s)
- Peter Schofield
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Kensington, Sydney, NSW 2010, Australia
| | - Alexander I Taylor
- MRC Laboratory of Molecular Biology, Cambridge CB2 2QH, UK
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), University of Cambridge, Cambridge CB2 0AW, UK
| | - Jérôme Rihon
- Rega Institute, Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Herestraat 49, B 3000, Leuven, Belgium
| | - Cristian D Peña Martinez
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Kensington, Sydney, NSW 2010, Australia
| | - Sacha Zinn
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Kensington, Sydney, NSW 2010, Australia
| | - Charles-Alexandre Mattelaer
- Rega Institute, Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Herestraat 49, B 3000, Leuven, Belgium
| | - Jennifer Jackson
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
| | - Gurpreet Dhaliwal
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), University of Cambridge, Cambridge CB2 0AW, UK
| | - Guy Schepers
- Rega Institute, Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Herestraat 49, B 3000, Leuven, Belgium
| | - Piet Herdewijn
- Rega Institute, Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Herestraat 49, B 3000, Leuven, Belgium
| | - Eveline Lescrinier
- Rega Institute, Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Herestraat 49, B 3000, Leuven, Belgium
| | - Daniel Christ
- Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
- St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Kensington, Sydney, NSW 2010, Australia
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2
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Rietmeyer L, Li De La Sierra-Gallay I, Schepers G, Dorchêne D, Iannazzo L, Patin D, Touzé T, van Tilbeurgh H, Herdewijn P, Ethève-Quelquejeu M, Fonvielle M. Amino-acyl tXNA as inhibitors or amino acid donors in peptide synthesis. Nucleic Acids Res 2022; 50:11415-11425. [PMID: 36350642 PMCID: PMC9723616 DOI: 10.1093/nar/gkac1023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 11/10/2022] Open
Abstract
Xenobiotic nucleic acids (XNAs) offer tremendous potential for synthetic biology, biotechnology, and molecular medicine but their ability to mimic nucleic acids still needs to be explored. Here, to study the ability of XNA oligonucleotides to mimic tRNA, we synthesized three L-Ala-tXNAs analogs. These molecules were used in a non-ribosomal peptide synthesis involving a bacterial Fem transferase. We compared the ability of this enzyme to use amino-acyl tXNAs containing 1',5'-anhydrohexitol (HNA), 2'-fluoro ribose (2'F-RNA) and 2'-fluoro arabinose. L-Ala-tXNA containing HNA or 2'F-RNA were substrates of the Fem enzyme. The synthesis of peptidyl-XNA and the resolution of their structures in complex with the enzyme show the impact of the XNA on protein binding. For the first time we describe functional tXNA in an in vitro assay. These results invite to test tXNA also as substitute for tRNA in translation.
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Affiliation(s)
| | | | - Guy Schepers
- Laboratory of Medicinal Chemistry, Rega Institute for Biomedical Research, KU Leuven, Herestraat 49, Box 1041, 3000 Leuven, Belgium
| | - Delphine Dorchêne
- INSERM UMR-S 1138, Centre de Recherche des Cordeliers, Sorbonne Université, Université Paris Cité, F-75006 Paris, France
| | - Laura Iannazzo
- Université Paris Cité, CNRS UMR 8601, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, F-75006Paris, France
| | - Delphine Patin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay 91198, Gif-sur-Yvette, France
| | - Thierry Touzé
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay 91198, Gif-sur-Yvette, France
| | - Herman van Tilbeurgh
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay 91198, Gif-sur-Yvette, France
| | - Piet Herdewijn
- Laboratory of Medicinal Chemistry, Rega Institute for Biomedical Research, KU Leuven, Herestraat 49, Box 1041, 3000 Leuven, Belgium
| | - Mélanie Ethève-Quelquejeu
- Université Paris Cité, CNRS UMR 8601, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, F-75006Paris, France
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3
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Liczner C, Duke K, Juneau G, Egli M, Wilds CJ. Beyond ribose and phosphate: Selected nucleic acid modifications for structure-function investigations and therapeutic applications. Beilstein J Org Chem 2021; 17:908-931. [PMID: 33981365 PMCID: PMC8093555 DOI: 10.3762/bjoc.17.76] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 04/14/2021] [Indexed: 12/16/2022] Open
Abstract
Over the past 25 years, the acceleration of achievements in the development of oligonucleotide-based therapeutics has resulted in numerous new drugs making it to the market for the treatment of various diseases. Oligonucleotides with alterations to their scaffold, prepared with modified nucleosides and solid-phase synthesis, have yielded molecules with interesting biophysical properties that bind to their targets and are tolerated by the cellular machinery to elicit a therapeutic outcome. Structural techniques, such as crystallography, have provided insights to rationalize numerous properties including binding affinity, nuclease stability, and trends observed in the gene silencing. In this review, we discuss the chemistry, biophysical, and structural properties of a number of chemically modified oligonucleotides that have been explored for gene silencing.
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Affiliation(s)
- Christopher Liczner
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Québec H4B 1R6, Canada
| | - Kieran Duke
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Québec H4B 1R6, Canada
| | - Gabrielle Juneau
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Québec H4B 1R6, Canada
| | - Martin Egli
- Department of Biochemistry, Vanderbilt Institute of Chemical Biology, and Center for Structural Biology, School of Medicine, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Christopher J Wilds
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Québec H4B 1R6, Canada
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4
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Structural Studies of HNA Substrate Specificity in Mutants of an Archaeal DNA Polymerase Obtained by Directed Evolution. Biomolecules 2020; 10:biom10121647. [PMID: 33302546 PMCID: PMC7763228 DOI: 10.3390/biom10121647] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/30/2020] [Accepted: 12/02/2020] [Indexed: 02/05/2023] Open
Abstract
Archaeal DNA polymerases from the B-family (polB) have found essential applications in biotechnology. In addition, some of their variants can accept a wide range of modified nucleotides or xenobiotic nucleotides, such as 1,5-anhydrohexitol nucleic acid (HNA), which has the unique ability to selectively cross-pair with DNA and RNA. This capacity is essential to allow the transmission of information between different chemistries of nucleic acid molecules. Variants of the archaeal polymerase from Thermococcus gorgonarius, TgoT, that can either generate HNA from DNA (TgoT_6G12) or DNA from HNA (TgoT_RT521) have been previously identified. To understand how DNA and HNA are recognized and selected by these two laboratory-evolved polymerases, we report six X-ray structures of these variants, as well as an in silico model of a ternary complex with HNA. Structural comparisons of the apo form of TgoT_6G12 together with its binary and ternary complexes with a DNA duplex highlight an ensemble of interactions and conformational changes required to promote DNA or HNA synthesis. MD simulations of the ternary complex suggest that the HNA-DNA hybrid duplex remains stable in the A-DNA helical form and help explain the presence of mutations in regions that would normally not be in contact with the DNA if it were not in the A-helical form. One complex with two incorporated HNA nucleotides is surprisingly found in a one nucleotide-backtracked form, which is new for a DNA polymerase. This information can be used for engineering a new generation of more efficient HNA polymerase variants.
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Intrastrand backbone-nucleobase interactions stabilize unwound right-handed helical structures of heteroduplexes of L-aTNA/RNA and SNA/RNA. Commun Chem 2020; 3:156. [PMID: 36703369 PMCID: PMC9814321 DOI: 10.1038/s42004-020-00400-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 10/12/2020] [Indexed: 01/29/2023] Open
Abstract
Xeno nucleic acids, which are synthetic analogues of natural nucleic acids, have potential for use in nucleic acid drugs and as orthogonal genetic biopolymers and prebiotic precursors. Although few acyclic nucleic acids can stably bind to RNA and DNA, serinol nucleic acid (SNA) and L-threoninol nucleic acid (L-aTNA) stably bind to them. Here we disclose crystal structures of RNA hybridizing with SNA and with L-aTNA. The heteroduplexes show unwound right-handed helical structures. Unlike canonical A-type duplexes, the base pairs in the heteroduplexes align perpendicularly to the helical axes, and consequently helical pitches are large. The unwound helical structures originate from interactions between nucleobases and neighbouring backbones of L-aTNA and SNA through CH-O bonds. In addition, SNA and L-aTNA form a triplex structure via C:G*G parallel Hoogsteen interactions with RNA. The unique structural features of the RNA-recognizing mode of L-aTNA and SNA should prove useful in nanotechnology, biotechnology, and basic research into prebiotic chemistry.
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6
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Chaput JC, Herdewijn P, Hollenstein M. Orthogonal Genetic Systems. Chembiochem 2020; 21:1408-1411. [PMID: 31889390 DOI: 10.1002/cbic.201900725] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Indexed: 01/02/2023]
Abstract
Xenobiology is an emerging area of synthetic biology that aims to safeguard genetically engineered cells by storing synthetic biology information in xeno-nucleic acid polymers (XNAs). Critical to the success of this effort is the need to establish cellular systems that can maintain an XNA chromosome in actively dividing cells. This viewpoint discusses the structural parameters of the nucleic acid backbone that should be considered when designing an orthogonal genetic system that can replicate without interference from the endogenous genome. In addition to practical value, these studies have the potential to provide new fundamental insight into the structure and function properties of unnatural nucleic acid polymers.
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Affiliation(s)
- John C Chaput
- Departments of Pharmaceutical Sciences, Chemistry, and Molecular Biology and Biochemistry, University of California, 101 Theory, Irvine, CA, 92617, USA
| | - Piet Herdewijn
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, Box 1041, 3000, Leuven, Belgium
| | - Marcel Hollenstein
- Department of Structural Biology and Chemistry, Institut Pasteur, 28 rue du Docteur Roux, 75724, Paris, France
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7
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Istrate A, Johannsen S, Istrate A, Sigel RKO, Leumann CJ. NMR solution structure of tricyclo-DNA containing duplexes: insight into enhanced thermal stability and nuclease resistance. Nucleic Acids Res 2019; 47:4872-4882. [PMID: 30916334 PMCID: PMC6511864 DOI: 10.1093/nar/gkz197] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 03/12/2019] [Accepted: 03/13/2019] [Indexed: 01/14/2023] Open
Abstract
Tc-DNA is a conformationally constrained oligonucleotide analogue which shows significant increase in thermal stability when hybridized with RNA, DNA or tc-DNA. Remarkably, recent studies revealed that tc-DNA antisense oligonucleotides (AO) hold great promise for the treatment of Duchenne muscular dystrophy and spinal muscular atrophy. To date, no high-resolution structural data is available for fully modified tc-DNA duplexes and little is known about the origins of their enhanced thermal stability. Here, we report the structures of a fully modified tc-DNA oligonucleotide paired with either complementary RNA, DNA or tc-DNA. All three investigated duplexes maintain a right-handed helical structure with Watson-Crick base pairing and overall geometry intermediate between A- and B-type, but closer to A-type structures. All sugars of the tc-DNA and RNA residues adopt a North conformation whereas the DNA deoxyribose are found in a South-East-North conformation equilibrium. The conformation of the tc-DNA strand in the three determined structures is nearly identical and despite the different nature and local geometry of the complementary strand, the overall structures of the examined duplexes are very similar suggesting that the tc-DNA strand dominates the duplex structure.
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Affiliation(s)
- Andrei Istrate
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, Bern CH-3012, Switzerland
| | - Silke Johannsen
- Department of Chemistry, Winterthurerstrasse 190, University of Zürich, Zürich CH-8057, Switzerland
| | - Alena Istrate
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, Bern CH-3012, Switzerland
| | - Roland K O Sigel
- Department of Chemistry, Winterthurerstrasse 190, University of Zürich, Zürich CH-8057, Switzerland
| | - Christian J Leumann
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, Bern CH-3012, Switzerland
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8
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Vanmeert M, Razzokov J, Mirza MU, Weeks SD, Schepers G, Bogaerts A, Rozenski J, Froeyen M, Herdewijn P, Pinheiro VB, Lescrinier E. Rational design of an XNA ligase through docking of unbound nucleic acids to toroidal proteins. Nucleic Acids Res 2019; 47:7130-7142. [PMID: 31334814 PMCID: PMC6649754 DOI: 10.1093/nar/gkz551] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/24/2019] [Accepted: 06/12/2019] [Indexed: 02/06/2023] Open
Abstract
Xenobiotic nucleic acids (XNA) are nucleic acid analogues not present in nature that can be used for the storage of genetic information. In vivo XNA applications could be developed into novel biocontainment strategies, but are currently limited by the challenge of developing XNA processing enzymes such as polymerases, ligases and nucleases. Here, we present a structure-guided modelling-based strategy for the rational design of those enzymes essential for the development of XNA molecular biology. Docking of protein domains to unbound double-stranded nucleic acids is used to generate a first approximation of the extensive interaction of nucleic acid processing enzymes with their substrate. Molecular dynamics is used to optimise that prediction allowing, for the first time, the accurate prediction of how proteins that form toroidal complexes with nucleic acids interact with their substrate. Using the Chlorella virus DNA ligase as a proof of principle, we recapitulate the ligase's substrate specificity and successfully predict how to convert it into an XNA-templated XNA ligase.
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Affiliation(s)
- Michiel Vanmeert
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, box 1041, 3000 Leuven, Belgium
| | - Jamoliddin Razzokov
- Research group PLASMANT, Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Muhammad Usman Mirza
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, box 1041, 3000 Leuven, Belgium
- Centre for Research in Molecular Medicine (CRiMM), University of Lahore, Pakistan
| | - Stephen D Weeks
- Biocrystallography, KU Leuven, Herestraat 49, box 822, 3000 Leuven, Belgium
| | - Guy Schepers
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, box 1041, 3000 Leuven, Belgium
| | - Annemie Bogaerts
- Research group PLASMANT, Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Jef Rozenski
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, box 1041, 3000 Leuven, Belgium
| | - Mathy Froeyen
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, box 1041, 3000 Leuven, Belgium
| | - Piet Herdewijn
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, box 1041, 3000 Leuven, Belgium
| | - Vitor B Pinheiro
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, box 1041, 3000 Leuven, Belgium
- University College London, Department of Structural and Molecular Biology, Gower Street, London, WC1E 6BT, UK
| | - Eveline Lescrinier
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, box 1041, 3000 Leuven, Belgium
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Froeyen M, Abu el Asrar R, Abramov M, Herdewijn P. Molecular simulation of cyclohexanyl nucleic acid (CNA) duplexes with CNA, DNA and RNA and CNA triloop and tetraloop hairpin structures. Bioorg Med Chem 2016; 24:1778-85. [PMID: 26968651 DOI: 10.1016/j.bmc.2016.03.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 02/29/2016] [Accepted: 03/02/2016] [Indexed: 01/09/2023]
Abstract
As part of a selection strategy for artificial nucleic acids (XNA) (to be considered as potential new information systems in vivo), we have carried out a modelling study on cyclohexanyl nucleic acids (CNA) duplexes and hairpins. CNA may form a duplex as well as hairpin structures, having the carbocyclic nucleosides in the (4)C1 conformation (with equatorial basis). The geometry of ds CNA is close to that of a HNA:RNA duplex. We demonstrated that CNA triphosphates function as a substrate for polymerases. Modelling experiments indicate that the monomers are probably presented to the polymerase in the (1)C4 conformation.
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Affiliation(s)
- Matheus Froeyen
- KU Leuven, Rega Institute for Medical Research, Medicinal Chemistry, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Rania Abu el Asrar
- KU Leuven, Rega Institute for Medical Research, Medicinal Chemistry, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Mikhail Abramov
- KU Leuven, Rega Institute for Medical Research, Medicinal Chemistry, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Piet Herdewijn
- KU Leuven, Rega Institute for Medical Research, Medicinal Chemistry, Minderbroedersstraat 10, 3000 Leuven, Belgium.
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10
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Anosova I, Kowal EA, Dunn MR, Chaput JC, Van Horn WD, Egli M. The structural diversity of artificial genetic polymers. Nucleic Acids Res 2015; 44:1007-21. [PMID: 26673703 PMCID: PMC4756832 DOI: 10.1093/nar/gkv1472] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 11/30/2015] [Indexed: 11/13/2022] Open
Abstract
Synthetic genetics is a subdiscipline of synthetic biology that aims to develop artificial genetic polymers (also referred to as xeno-nucleic acids or XNAs) that can replicate in vitro and eventually in model cellular organisms. This field of science combines organic chemistry with polymerase engineering to create alternative forms of DNA that can store genetic information and evolve in response to external stimuli. Practitioners of synthetic genetics postulate that XNA could be used to safeguard synthetic biology organisms by storing genetic information in orthogonal chromosomes. XNA polymers are also under active investigation as a source of nuclease resistant affinity reagents (aptamers) and catalysts (xenozymes) with practical applications in disease diagnosis and treatment. In this review, we provide a structural perspective on known antiparallel duplex structures in which at least one strand of the Watson-Crick duplex is composed entirely of XNA. Currently, only a handful of XNA structures have been archived in the Protein Data Bank as compared to the more than 100 000 structures that are now available. Given the growing interest in xenobiology projects, we chose to compare the structural features of XNA polymers and discuss their potential to access new regions of nucleic acid fold space.
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Affiliation(s)
- Irina Anosova
- The Biodesign Institute, Virginia G. Piper Center for Personalized Diagnostics, School of Molecular Sciences, Magnetic Resonance Research Center, Arizona State University, Tempe, AZ 85287-5001, USA
| | - Ewa A Kowal
- Department of Biochemistry, Center for Structural Biology, and Vanderbilt Ingram Cancer Center, Vanderbilt University, School of Medicine, Nashville, TN 37232-0146, USA
| | - Matthew R Dunn
- Department of Pharmaceutical Sciences, University of California-Irvine, Irvine, CA 92697, USA
| | - John C Chaput
- Department of Pharmaceutical Sciences, University of California-Irvine, Irvine, CA 92697, USA
| | - Wade D Van Horn
- The Biodesign Institute, Virginia G. Piper Center for Personalized Diagnostics, School of Molecular Sciences, Magnetic Resonance Research Center, Arizona State University, Tempe, AZ 85287-5001, USA
| | - Martin Egli
- Department of Biochemistry, Center for Structural Biology, and Vanderbilt Ingram Cancer Center, Vanderbilt University, School of Medicine, Nashville, TN 37232-0146, USA
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11
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D'Alonzo D, Froeyen M, Schepers G, Di Fabio G, Van Aerschot A, Herdewijn P, Palumbo G, Guaragna A. 1',5'-Anhydro-L-ribo-hexitol Adenine Nucleic Acids (α-L-HNA-A): Synthesis and Chiral Selection Properties in the Mirror Image World. J Org Chem 2015; 80:5014-22. [PMID: 25853790 DOI: 10.1021/acs.joc.5b00406] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The synthesis and a preliminary investigation of the base pairing properties of (6' → 4')-linked 1',5'-anhydro-L-ribo-hexitol nucleic acids (α-L-HNA) have herein been reported through the study of a model oligoadenylate system in the mirror image world. Despite its considerable preorganization due to the rigidity of the "all equatorial" pyranyl sugar backbone, α-L-HNA represents a versatile informational biopolymer, in view of its capability to cross-communicate with natural and unnatural complements in both enantiomeric forms. This seems the result of an inherent flexibility of the oligonucleotide system, as witnessed by the singular formation of iso- and heterochiral associations composed of regular, enantiomorphic helical structures. The peculiar properties of α-L-HNA (and most generally of the α-HNA system) provide new elements in our understanding of the structural prerequisites ruling the stereoselectivity of the hybridization processes of nucleic acids.
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Affiliation(s)
- Daniele D'Alonzo
- †Dipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, via Cintia 21, 80126 Napoli, Italy
| | - Mathy Froeyen
- ‡Laboratory for Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Guy Schepers
- ‡Laboratory for Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Giovanni Di Fabio
- †Dipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, via Cintia 21, 80126 Napoli, Italy
| | - Arthur Van Aerschot
- ‡Laboratory for Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Piet Herdewijn
- ‡Laboratory for Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium
| | - Giovanni Palumbo
- †Dipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, via Cintia 21, 80126 Napoli, Italy
| | - Annalisa Guaragna
- †Dipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, via Cintia 21, 80126 Napoli, Italy
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12
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Seth PP, Swayze EE. Unnatural Nucleoside Analogs for Antisense Therapy. METHODS AND PRINCIPLES IN MEDICINAL CHEMISTRY 2014. [DOI: 10.1002/9783527676545.ch12] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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13
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Migawa MT, Prakash TP, Vasquez G, Seth PP, Swayze EE. Synthesis and biophysical properties of constrained D-altritol nucleic acids (cANA). Org Lett 2013; 15:4316-9. [PMID: 23937264 DOI: 10.1021/ol401730d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The first synthesis of constrained altritol nucleic acids (cANA) containing antisense oligonucleotides (ASOs) was carried out to ascertain how conformationally restricting the D-altritol backbone-containing ASO (Me-ANA) would affect their ability to form duplexes with RNA. It was found that the thermal stability was reduced (cANA/RNA -1.1 °C/modification) compared to DNA/RNA, suggesting the constrained system results in a small destabilizing perturbation in the duplex structure.
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Affiliation(s)
- Michael T Migawa
- Department of Medicinal Chemistry, Isis Pharmaceuticals, Inc., 2855 Gazelle Court, Carlsbad, California 92010, USA.
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14
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Abstract
For over 20 years, laboratories around the world have been applying the principles of Darwinian evolution to isolate DNA and RNA molecules with specific ligand-binding or catalytic activities. This area of synthetic biology, commonly referred to as in vitro genetics, is made possible by the availability of natural polymerases that can replicate genetic information in the laboratory. Moving beyond natural nucleic acids requires organic chemistry to synthesize unnatural analogues and polymerase engineering to create enzymes that recognize artificial substrates. Progress in both of these areas has led to the emerging field of synthetic genetics, which explores the structural and functional properties of synthetic genetic polymers by in vitro evolution. This review examines recent advances in the Darwinian evolution of artificial genetic polymers and their potential downstream applications in exobiology, molecular medicine, and synthetic biology.
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Affiliation(s)
- John C Chaput
- Center for Evolutionary Medicine and Informatics in the Biodesign Institute, and Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287-5301, USA.
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15
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Ovaere M, Sponer J, Sponer JE, Herdewijn P, Van Meervelt L. How does hydroxyl introduction influence the double helical structure: the stabilization of an altritol nucleic acid:ribonucleic acid duplex. Nucleic Acids Res 2012; 40:7573-83. [PMID: 22638588 PMCID: PMC3424580 DOI: 10.1093/nar/gks470] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 04/30/2012] [Accepted: 05/02/2012] [Indexed: 01/24/2023] Open
Abstract
Altritol nucleic acids (ANAs) are a promising new tool in the development of artificial small interfering ribonucleic acids (siRNAs) for therapeutical applications. To mimic the siRNA:messenger RNA (mRNA) interactions, the crystal structure of the ANA:RNA construct a(CCGUAAUGCC-P):r(GGCAUUACGG) was determined to 1.96 Å resolution which revealed the hybrid to form an A-type helix. As this A-form is a major requirement in the RNAi process, this crystal structure confirms the potential of altritol-modified siRNAs. Moreover, in the ANA strands, a new type of intrastrand interactions was found between the O2' hydroxyl group of one residue and the sugar ring O4' atom of the next residue. These interactions were further investigated by quantum chemical methods. Besides hydration effects, these intrastrand hydrogen bonds may also contribute to the stability of ANA:RNA duplexes.
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Affiliation(s)
- Margriet Ovaere
- Department of Chemistry, Katholieke Universiteit Leuven, Biomolecular Architecture and BioMacS, Celestijnenlaan 200F, B-3001 Leuven, Belgium, Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, CZ-61265, Brno, Czech Republic, CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic and Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Rega Institute for Medical Research and BioMacS, Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Jiri Sponer
- Department of Chemistry, Katholieke Universiteit Leuven, Biomolecular Architecture and BioMacS, Celestijnenlaan 200F, B-3001 Leuven, Belgium, Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, CZ-61265, Brno, Czech Republic, CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic and Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Rega Institute for Medical Research and BioMacS, Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Judit E. Sponer
- Department of Chemistry, Katholieke Universiteit Leuven, Biomolecular Architecture and BioMacS, Celestijnenlaan 200F, B-3001 Leuven, Belgium, Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, CZ-61265, Brno, Czech Republic, CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic and Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Rega Institute for Medical Research and BioMacS, Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Piet Herdewijn
- Department of Chemistry, Katholieke Universiteit Leuven, Biomolecular Architecture and BioMacS, Celestijnenlaan 200F, B-3001 Leuven, Belgium, Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, CZ-61265, Brno, Czech Republic, CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic and Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Rega Institute for Medical Research and BioMacS, Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Luc Van Meervelt
- Department of Chemistry, Katholieke Universiteit Leuven, Biomolecular Architecture and BioMacS, Celestijnenlaan 200F, B-3001 Leuven, Belgium, Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, CZ-61265, Brno, Czech Republic, CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic and Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Rega Institute for Medical Research and BioMacS, Minderbroedersstraat 10, B-3000 Leuven, Belgium
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16
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Maiti M, Nauwelaerts K, Lescrinier E, Herdewijn P. Structural and binding study of modified siRNAs with the Argonaute 2 PAZ domain by NMR spectroscopy. Chemistry 2011; 17:1519-28. [PMID: 21268154 DOI: 10.1002/chem.201000765] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Indexed: 11/05/2022]
Abstract
By using high-resolution NMR spectroscopy, the structures of a natural short interfering RNA (siRNA) and of several altritol nucleic acid (ANA)-modified siRNAs were determined. The interaction of modified siRNAs with the PAZ domain of the Argonaute 2 protein of Drosophila melanogaster was also studied. The structures show that the modified siRNA duplexes (ANA/RNA) adopt a geometry very similar to the naturally occurring A-type siRNA duplex. All ribose residues, except for the 3' overhang, show 3'-endo conformation. The six-membered altritol sugar in ANA occurs in a chair conformation with the nucleobase in an axial position. In all siRNA duplexes, two overhanging nucleotides at the 3' end enhance the stability of the first neighboring base pair by a stacking interaction. The first overhanging nucleotide has a rather fixed position, whereas the second overhanging nucleotide shows larger flexibility. NMR binding studies of the PAZ domain with ANA-modified siRNAs demonstrate that modifications in the double-stranded region of the antisense strand have some small effects on the binding affinity as compared with the unmodified siRNA. Modification of the 3' overhang with thymidine (dTdT) residues shows a sixfold increase in the binding affinity compared with the unmodified siRNA (relative binding affinity of 17% compared with dTdT-modified overhang), whereas modification of the 3' overhang with ANA largely decreases the binding affinity.
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Affiliation(s)
- Mohitosh Maiti
- Laboratory of Medicinal Chemistry, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium
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17
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Abstract
Starting from pyranose nucleic acids, several series of modified nucleic acids with a six-membered carbohydrate moiety (mimic) have been synthesized and analyzed over a period of 20 years, and this work is summarized here. The process starts with structural and conformational considerations, followed by synthetic efforts and a structural analysis, and ends up with a biological confirmation of the concept, demonstrating that these modified nucleic acids represent very valuable tools in chemistry and biology.
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Affiliation(s)
- Piet Herdewijn
- Laboratory for Medicinal Chemistry, Rega Institute for Medical Research, Minderbroedersstraat 10, B-3000 Leuven.
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18
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Egli M, Pallan PS. Crystallographic studies of chemically modified nucleic acids: a backward glance. Chem Biodivers 2010; 7:60-89. [PMID: 20087997 PMCID: PMC2905155 DOI: 10.1002/cbdv.200900177] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Chemically modified nucleic acids (CNAs) are widely explored as antisense oligonucleotide or small interfering RNA (siRNA) candidates for therapeutic applications. CNAs are also of interest in diagnostics, high-throughput genomics and target validation, nanotechnology and as model systems in investigations directed at a better understanding of the etiology of nucleic acid structure, as well as the physicochemical and pairing properties of DNA and RNA, and for probing protein-nucleic acid interactions. In this article, we review research conducted in our laboratory over the past two decades with a focus on crystal-structure analyses of CNAs and artificial pairing systems. We highlight key insights into issues ranging from conformational distortions as a consequence of modification to the modulation of pairing strength, and RNA affinity by stereoelectronic effects and hydration. Although crystal structures have only been determined for a subset of the large number of modifications that were synthesized and analyzed in the oligonucleotide context to date, they have yielded guiding principles for the design of new analogs with tailor-made properties, including pairing specificity, nuclease resistance, and cellular uptake. And, perhaps less obviously, crystallographic studies of CNAs and synthetic pairing systems have shed light on fundamental aspects of DNA and RNA structure and function that would not have been disclosed by investigations solely focused on the natural nucleic acids.
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Affiliation(s)
- Martin Egli
- Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, Tennessee 37232-0146, USA.
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19
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Loakes D, Holliger P. Polymerase engineering: towards the encoded synthesis of unnatural biopolymers. Chem Commun (Camb) 2009:4619-31. [PMID: 19641798 DOI: 10.1039/b903307f] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
DNA is not only a repository of genetic information for life, it is also a unique polymer with remarkable properties: it associates according to well-defined rules, it can be assembled into diverse nanostructures of defined geometry, it can be evolved to bind ligands and catalyse chemical reactions and it can serve as a supramolecular scaffold to arrange chemical groups in space. However, its chemical makeup is rather uniform and the physicochemical properties of the four canonical bases only span a narrow range. Much wider chemical diversity is accessible through solid-phase synthesis but oligomers are limited to <100 nucleotides and variations in chemistry can usually not be replicated and thus are not amenable to evolution. Recent advances in nucleic acid chemistry and polymerase engineering promise to bring the synthesis, replication and ultimately evolution of nucleic acid polymers with greatly expanded chemical diversity within our reach.
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Affiliation(s)
- David Loakes
- Medical Research Council, Laboratory of Molecular Biology, Hills Road, Cambridge, Cambridgeshire, UKCB2 0QH
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20
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Loakes D, Holliger P. Darwinian chemistry: towards the synthesis of a simple cell. MOLECULAR BIOSYSTEMS 2009; 5:686-94. [PMID: 19562107 DOI: 10.1039/b904024b] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The total synthesis of a simple cell is in many ways the ultimate challenge in synthetic biology. Outlined eight years ago in a visionary article by Szostak et al. (J. W. Szostak, D. P. Bartel and P. L. Luisi, Nature, 2001, 409, 387), the chances of success seemed remote. However, recent progress in nucleic acid chemistry, directed evolution and membrane biophysics have brought the prospect of a simple synthetic cell with life-like properties such as growth, division, heredity and evolution within reach. Success in this area will not only revolutionize our understanding of abiogenesis but provide a fertile test-bed for models of prebiotic chemistry and early evolution. Last but not least, a robust "living" protocell may provide a versatile and safe chassis for embedding synthetic devices and systems.
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Affiliation(s)
- David Loakes
- Medical Research Council, Laboratory of Molecular Biology, Hills Road, Cambridge, CB2 0QH, UK
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21
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Abstract
There is a general interest in designing biomimetic materials, such as the double helical structures of biopolymers, by the self-assembly of synthetic organic moieties. This interest stems from their structural versatility, biocompatibility, robustness and a relative experimental simplicity. The self-assembly process requires a combination of several non-covalent interactions between two intertwined strands. Besides the combination of metal-ligand binding, base pair interactions and peptide stacking interactions, in the last few years, hybridized synthetic foldamers have proven to be useful in this context. The molecular rigidity and the extent of intra- vs. intermolecular interactions within the strand play an important role in the intertwining processes. A dynamic equilibrium exists between the monomer and the dimer. In general, the combination of the enthalpic gain (from the interaction of the two strands) and entropic loss (upon hybridization) controls the duplex formation. There are now a variety of metal-free double helices from abiotic backbones, with potential applications in antigene therapy, studies on evolution and conducting materials. A tutorial review of some general guidelines and illustrative examples is presented.
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Affiliation(s)
- Debasish Haldar
- Institut für Organische Chemie, Fachbereich Chemie, Universität Duisburg-Essen, Universitätsstrasse 2, 45141 Essen, Germany
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22
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Egli M, Pallan PS. Insights from crystallographic studies into the structural and pairing properties of nucleic acid analogs and chemically modified DNA and RNA oligonucleotides. ACTA ACUST UNITED AC 2007; 36:281-305. [PMID: 17288535 DOI: 10.1146/annurev.biophys.36.040306.132556] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Chemically modified nucleic acids function as model systems for native DNA and RNA; as chemical probes in diagnostics or the analysis of protein-nucleic acid interactions and in high-throughput genomics and drug target validation; as potential antigene-, antisense-, or RNAi-based drugs; and as tools for structure determination (i.e., crystallographic phasing), just to name a few. Biophysical and structural investigations of chemically modified DNAs and RNAs, particularly of nucleic acid analogs with more significant alterations to the well-known base-sugar-phosphate framework (i.e., peptide or hexopyranose nucleic acids), can also provide insights into the properties of the natural nucleic acids that are beyond the reach of studies focusing on DNA or RNA alone. In this review we summarize results from crystallographic analyses of chemically modified DNAs and RNAs that are primarily of interest in the context of the discovery and development of oligonucleotide-based therapeutics. In addition, we re-examine recent structural data on nucleic acid analogs that are investigated as part of a systematic effort to rationalize nature's choice of pentose in the genetic system.
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Affiliation(s)
- Martin Egli
- Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, Tennessee 37232, USA.
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23
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Froeyen M, Morvan F, Vasseur JJ, Nielsen P, Van Aerschot A, Rosemeyer H, Herdewijn P. Conformational and chiral selection of oligonucleotides. Chem Biodivers 2007; 4:803-17. [PMID: 17443890 DOI: 10.1002/cbdv.200790065] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In view of a better understanding of chiral selection of oligonucleotides, we have studied the hybridization of D- and L-CNA (cyclohexane nucleic acids) and D- and L-DNA, with chiral D-beta-homo-DNA and achiral PNA (peptide nucleic acids). PNA hybridizes as well with D-DNA, L-DNA as with D-beta-homo-DNA. The structure of the PNA x D-beta-homo-DNA complex is different from the PNA x DNA duplexes. D-CNA prefers D-DNA as hybridization partner, while L-CNA prefers D-beta-homo-DNA as hybridization partner. The conformation of the enantiomeric oligonucleotides D-CNA and L-CNA in the supramolecular complex with D-DNA and D-beta-homo-DNA, respectively, is different. These data may contribute to the confirmation of a hypothesis of the existence of achiral informative polymers as RNA predecessor, and to the understanding of homochirality of nucleic acids.
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Affiliation(s)
- Matheus Froeyen
- Laboratory of Medicinal Chemistry, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven
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24
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Förster C, Brauer ABE, Brode S, Schmidt KS, Perbandt M, Meyer A, Rypniewski W, Betzel C, Kurreck J, Fürste JP, Erdmann VA. Comparative crystallization and preliminary X-ray diffraction studies of locked nucleic acid and RNA stems of a tenascin C-binding aptamer. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:665-8. [PMID: 16820689 PMCID: PMC2242942 DOI: 10.1107/s1744309106020343] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2006] [Accepted: 05/30/2006] [Indexed: 11/11/2022]
Abstract
The pharmacokinetic properties of an aptamer against the tumour-marker protein tenascin-C have recently been successfully improved by the introduction of locked nucleic acids (LNAs) into the terminal stem of the aptamer. Since it is believed that this post-SELEX optimization is likely to provide a more general route to enhance the in vitro and in vivo stability of aptamers, elucidation of the structural basis of this improvement was embarked upon. Here, the crystallographic and X-ray diffraction data of the isolated aptamer stem encompassed in a six-base-pair duplex both with and without the LNA modification are presented. The obtained all-LNA crystals belong to space group P4(1)2(1)2 or P4(3)2(1)2, with unit-cell parameters a = b = 52.80, c = 62.83 angstroms; the all-RNA crystals belong to space group R32, with unit-cell parameters a = b = 45.21, c = 186.97 angstroms, gamma = 120.00 degrees.
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Affiliation(s)
- Charlotte Förster
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Arnd B. E. Brauer
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Svenja Brode
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Kathrin S. Schmidt
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Markus Perbandt
- Institute of Biochemistry and Food Chemistry, University of Hamburg, c/o DESY, Notkestrasse 85, Building 22a, 22603 Hamburg, Germany
| | - Arne Meyer
- Institute of Biochemistry and Food Chemistry, University of Hamburg, c/o DESY, Notkestrasse 85, Building 22a, 22603 Hamburg, Germany
| | - Wojciech Rypniewski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Z. Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Christian Betzel
- Institute of Biochemistry and Food Chemistry, University of Hamburg, c/o DESY, Notkestrasse 85, Building 22a, 22603 Hamburg, Germany
| | - Jens Kurreck
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Jens P. Fürste
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Volker A. Erdmann
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
- Correspondence e-mail:
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Herdewijn P. The interplay between antiviral activity, oligonucleotide hybridisation and nucleic acids incorporation studies. Antiviral Res 2006; 71:317-21. [PMID: 16690140 DOI: 10.1016/j.antiviral.2006.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2006] [Revised: 04/04/2006] [Accepted: 04/04/2006] [Indexed: 11/22/2022]
Abstract
Nucleoside analogues have been the most successful antiviral compounds. Likewise, they are the most intriguing antiviral compounds, because of their structural relationship to natural nucleosides. This is also the reason why the design process of a potential selective antiviral nucleoside is so difficult. Too many natural processes (from cellular uptake to DNA incorporation) and too many enzymes are involved in their biological effect (activity/toxicity/catabolism/anabolism) to make the design process readily predictable. The relationship between the physicochemical and biochemical properties of nucleoside analogues and their antiviral activity is very complex and could only be understood on a very long term basis. Here we try to explain some of the reasoning that was made during the design process leading to new potent antivirals with a phosphonate functionality.
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Affiliation(s)
- Piet Herdewijn
- Rega Institute for Medical Research, Laboratory of Medicinal Chemistry, Minderbroedersstraat 10, B-3000 Leuven, Belgium.
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