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Miao Q, Nitsche C, Orton H, Overhand M, Otting G, Ubbink M. Paramagnetic Chemical Probes for Studying Biological Macromolecules. Chem Rev 2022; 122:9571-9642. [PMID: 35084831 PMCID: PMC9136935 DOI: 10.1021/acs.chemrev.1c00708] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Indexed: 12/11/2022]
Abstract
Paramagnetic chemical probes have been used in electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopy for more than four decades. Recent years witnessed a great increase in the variety of probes for the study of biological macromolecules (proteins, nucleic acids, and oligosaccharides). This Review aims to provide a comprehensive overview of the existing paramagnetic chemical probes, including chemical synthetic approaches, functional properties, and selected applications. Recent developments have seen, in particular, a rapid expansion of the range of lanthanoid probes with anisotropic magnetic susceptibilities for the generation of structural restraints based on residual dipolar couplings and pseudocontact shifts in solution and solid state NMR spectroscopy, mostly for protein studies. Also many new isotropic paramagnetic probes, suitable for NMR measurements of paramagnetic relaxation enhancements, as well as EPR spectroscopic studies (in particular double resonance techniques) have been developed and employed to investigate biological macromolecules. Notwithstanding the large number of reported probes, only few have found broad application and further development of probes for dedicated applications is foreseen.
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Affiliation(s)
- Qing Miao
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
- School
of Chemistry &Chemical Engineering, Shaanxi University of Science & Technology, Xi’an710021, China
| | - Christoph Nitsche
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Henry Orton
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
- ARC
Centre of Excellence for Innovations in Peptide & Protein Science,
Research School of Chemistry, Australian
National University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Mark Overhand
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Gottfried Otting
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
- ARC
Centre of Excellence for Innovations in Peptide & Protein Science,
Research School of Chemistry, Australian
National University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Marcellus Ubbink
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
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2
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Heinz M, Erlenbach N, Stelzl LS, Thierolf G, Kamble NR, Sigurdsson ST, Prisner TF, Hummer G. High-resolution EPR distance measurements on RNA and DNA with the non-covalent Ǵ spin label. Nucleic Acids Res 2020; 48:924-933. [PMID: 31777925 PMCID: PMC6954412 DOI: 10.1093/nar/gkz1096] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 11/01/2019] [Accepted: 11/20/2019] [Indexed: 12/25/2022] Open
Abstract
Pulsed electron paramagnetic resonance (EPR) experiments, among them most prominently pulsed electron-electron double resonance experiments (PELDOR/DEER), resolve the conformational dynamics of nucleic acids with high resolution. The wide application of these powerful experiments is limited by the synthetic complexity of some of the best-performing spin labels. The recently developed $\bf\acute{G}$ (G-spin) label, an isoindoline-nitroxide derivative of guanine, can be incorporated non-covalently into DNA and RNA duplexes via Watson-Crick base pairing in an abasic site. We used PELDOR and molecular dynamics (MD) simulations to characterize $\bf\acute{G}$, obtaining excellent agreement between experiments and time traces calculated from MD simulations of RNA and DNA double helices with explicitly modeled $\bf\acute{G}$ bound in two abasic sites. The MD simulations reveal stable hydrogen bonds between the spin labels and the paired cytosines. The abasic sites do not significantly perturb the helical structure. $\bf\acute{G}$ remains rigidly bound to helical RNA and DNA. The distance distributions between the two bound $\bf\acute{G}$ labels are not substantially broadened by spin-label motions in the abasic site and agree well between experiment and MD. $\bf\acute{G}$ and similar non-covalently attached spin labels promise high-quality distance and orientation information, also of complexes of nucleic acids and proteins.
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Affiliation(s)
- Marcel Heinz
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, 60438 Frankfurt am Main, Germany
| | - Nicole Erlenbach
- Institute of Physical and Theoretical Chemistry and Center of Biomolecular Magnetic Resonance, Goethe University Frankfurt, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Lukas S Stelzl
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, 60438 Frankfurt am Main, Germany
| | - Grace Thierolf
- Institute of Physical and Theoretical Chemistry and Center of Biomolecular Magnetic Resonance, Goethe University Frankfurt, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Nilesh R Kamble
- Department of Chemistry, Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavk, Iceland
| | - Snorri Th Sigurdsson
- Department of Chemistry, Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavk, Iceland
| | - Thomas F Prisner
- Institute of Physical and Theoretical Chemistry and Center of Biomolecular Magnetic Resonance, Goethe University Frankfurt, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Gerhard Hummer
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, 60438 Frankfurt am Main, Germany
- Institute for Biophysics, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
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3
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Ding Y, Kathiresan V, Zhang X, Haworth IS, Qin PZ. Experimental Validation of the ALLNOX Program for Studying Protein-Nucleic Acid Complexes. J Phys Chem A 2019; 123:3592-3598. [PMID: 30978022 DOI: 10.1021/acs.jpca.9b01027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Measurement of distances between spectroscopic labels (e.g., spin labels, fluorophores) attached to specific sites of biomolecules is an important method for studying biomolecular complexes. ALLNOX (Addition of Labels and Linkers) has been developed as a program to model interlabel distances based on an input macromolecule structure. Here, we report validation of ALLNOX using measured distances between nitroxide spin labels attached to specific sites of a protein-DNA complex. The results demonstrate that ALLNOX predicts average interspin distances that matched with values measured with pairs of labels attached at the protein and/or DNA. This establishes a solid foundation for using spin labeling in conjunction with ALLNOX to investigate complexes without high-resolution structures. With its high degree of flexibility for the label or the target biomolecule, ALLNOX provides a useful tool for investigating the structure-function relationship in a large variety of biological molecules.
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Affiliation(s)
- Yuan Ding
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
| | - Venkatesan Kathiresan
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
| | - Xiaojun Zhang
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
| | - Ian S Haworth
- Department of Pharmacology and Pharmaceutical Sciences , University of Southern California , Los Angeles , California 90089 , United States
| | - Peter Z Qin
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States.,Department of Biological Sciences , University of Southern California , Los Angeles , California 90089 , United States
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4
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Chen Y, Lu Z, Chen D, Wei Y, Chen X, Huang J, Guan N, Lu Q, Wu R, Huang R. Transcriptomic analysis and driver mutant prioritization for differentially expressed genes from a Saccharomyces cerevisiae strain with high glucose tolerance generated by UV irradiation. RSC Adv 2017. [DOI: 10.1039/c7ra06146c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Driver mutations of a Saccharomyces cerevisiae mutant phenotype strain with high sugar tolerance were sought by the PheNetic network.
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Affiliation(s)
- Ying Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources
- Guangxi University
- Nanning
- P. R. China
- College of Life Science and Technology
| | - Zhilong Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources
- Guangxi University
- Nanning
- P. R. China
- College of Life Science and Technology
| | - Dong Chen
- National Engineering Research Center for Non-Food Biorefinery
- Guangxi Academy of Sciences
- Nanning
- P. R. China
| | - Yutuo Wei
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources
- Guangxi University
- Nanning
- P. R. China
- College of Life Science and Technology
| | - Xiaoling Chen
- National Engineering Research Center for Non-Food Biorefinery
- Guangxi Academy of Sciences
- Nanning
- P. R. China
| | - Jun Huang
- National Engineering Research Center for Non-Food Biorefinery
- Guangxi Academy of Sciences
- Nanning
- P. R. China
| | - Ni Guan
- National Engineering Research Center for Non-Food Biorefinery
- Guangxi Academy of Sciences
- Nanning
- P. R. China
| | - Qi Lu
- National Engineering Research Center for Non-Food Biorefinery
- Guangxi Academy of Sciences
- Nanning
- P. R. China
| | - Renzhi Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources
- Guangxi University
- Nanning
- P. R. China
- College of Life Science and Technology
| | - Ribo Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources
- Guangxi University
- Nanning
- P. R. China
- College of Life Science and Technology
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5
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Akiel RD, Zhang X, Abeywardana C, Stepanov V, Qin PZ, Takahashi S. Investigating Functional DNA Grafted on Nanodiamond Surface Using Site-Directed Spin Labeling and Electron Paramagnetic Resonance Spectroscopy. J Phys Chem B 2016; 120:4003-8. [PMID: 27058261 DOI: 10.1021/acs.jpcb.6b00790] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Nanodiamonds (NDs) are a new and attractive class of materials for sensing and delivery in biological systems. Methods for functionalizing ND surfaces are highly valuable in these applications, yet reported approaches for covalent modification with biological macromolecules are still limited, and characterizing behaviors of ND-tethered biomolecules is difficult. Here we demonstrated the use of copper-free click chemistry to covalently attach DNA strands at ND surfaces. Using site-directed spin labeling and electron paramagnetic resonance spectroscopy, we demonstrated that the tethered DNA strands maintain the ability to undergo repetitive hybridizations and behave similarly to those in solutions, maintaining a large degree of mobility with respect to the ND. The work established a method to prepare and characterize an easily addressable identity tag for NDs. This will open up future applications such as targeted ND delivery and developing sensors for investigating biomolecules.
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Affiliation(s)
- Rana D Akiel
- Department of Chemistry, ‡Department of Physics, and §Center for Quantum Information Science and Technology (CQIST), University of Southern California , Los Angeles, California 90089, United States
| | - Xiaojun Zhang
- Department of Chemistry, ‡Department of Physics, and §Center for Quantum Information Science and Technology (CQIST), University of Southern California , Los Angeles, California 90089, United States
| | - Chathuranga Abeywardana
- Department of Chemistry, ‡Department of Physics, and §Center for Quantum Information Science and Technology (CQIST), University of Southern California , Los Angeles, California 90089, United States
| | - Viktor Stepanov
- Department of Chemistry, ‡Department of Physics, and §Center for Quantum Information Science and Technology (CQIST), University of Southern California , Los Angeles, California 90089, United States
| | - Peter Z Qin
- Department of Chemistry, ‡Department of Physics, and §Center for Quantum Information Science and Technology (CQIST), University of Southern California , Los Angeles, California 90089, United States
| | - Susumu Takahashi
- Department of Chemistry, ‡Department of Physics, and §Center for Quantum Information Science and Technology (CQIST), University of Southern California , Los Angeles, California 90089, United States
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6
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7
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Zhang X, Xu CX, Di Felice R, Sponer J, Islam B, Stadlbauer P, Ding Y, Mao L, Mao ZW, Qin PZ. Conformations of Human Telomeric G-Quadruplex Studied Using a Nucleotide-Independent Nitroxide Label. Biochemistry 2015; 55:360-72. [PMID: 26678746 DOI: 10.1021/acs.biochem.5b01189] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Guanine-rich oligonucleotides can form a unique G-quadruplex (GQ) structure with stacking units of four guanine bases organized in a plane through Hoogsteen bonding. GQ structures have been detected in vivo and shown to exert their roles in maintaining genome integrity and regulating gene expression. Understanding GQ conformation is important for understanding its inherent biological role and for devising strategies to control and manipulate functions based on targeting GQ. Although a number of biophysical methods have been used to investigate structure and dynamics of GQs, our understanding is far from complete. As such, this work explores the use of the site-directed spin labeling technique, complemented by molecular dynamics simulations, for investigating GQ conformations. A nucleotide-independent nitroxide label (R5), which has been previously applied for probing conformations of noncoding RNA and DNA duplexes, is attached to multiple sites in a 22-nucleotide DNA strand derived from the human telomeric sequence (hTel-22) that is known to form GQ. The R5 labels are shown to minimally impact GQ folding, and inter-R5 distances measured using double electron-electron resonance spectroscopy are shown to adequately distinguish the different topological conformations of hTel-22 and report variations in their occupancies in response to changes of the environment variables such as salt, crowding agent, and small molecule ligand. The work demonstrates that the R5 label is able to probe GQ conformation and establishes the base for using R5 to study more complex sequences, such as those that may potentially form multimeric GQs in long telomeric repeats.
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Affiliation(s)
- Xiaojun Zhang
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
| | - Cui-Xia Xu
- School of Chemistry and Chemical Engineering, Sun Yat-Sen University , Guangzhou 510275, China
| | - Rosa Di Felice
- Department of Physics and Astronomy, University of Southern California , Los Angeles, California 90089, United States.,Center S3, CNR institute of Nanoscience , Modena, Italy
| | - Jiri Sponer
- Central European Institute of Technology (CEITEC), Masaryk University , Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic.,Institute of Biophysics, Academy of Sciences of the Czech Republic , Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Barira Islam
- Central European Institute of Technology (CEITEC), Masaryk University , Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Petr Stadlbauer
- Institute of Biophysics, Academy of Sciences of the Czech Republic , Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Yuan Ding
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
| | - Lingling Mao
- School of Chemistry and Chemical Engineering, Sun Yat-Sen University , Guangzhou 510275, China
| | - Zong-Wan Mao
- School of Chemistry and Chemical Engineering, Sun Yat-Sen University , Guangzhou 510275, China
| | - Peter Z Qin
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
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8
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Malygin AA, Graifer DM, Meschaninova MI, Venyaminova AG, Krumkacheva OA, Fedin MV, Karpova GG, Bagryanskaya EG. Doubly Spin-Labeled RNA as an EPR Reporter for Studying Multicomponent Supramolecular Assemblies. Biophys J 2015; 109:2637-2643. [PMID: 26682820 PMCID: PMC4699879 DOI: 10.1016/j.bpj.2015.10.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 10/21/2015] [Accepted: 10/30/2015] [Indexed: 02/06/2023] Open
Abstract
mRNAs are involved in complicated supramolecular complexes with human 40S and 80S ribosomes responsible for the protein synthesis. In this work, a derivative of nonaribonucleotide pUUCGUAAAA with nitroxide spin labels attached to the 5'-phosphate and to the C8 atom of the adenosine in sixth position (mRNA analog) was used for studying such complexes using double electron-electron resonance/pulsed electron-electron double resonance spectroscopy. The complexes were assembled with participation of tRNA(Phe), which targeted triplet UUC of the derivative to the ribosomal peptidyl site and predetermined location of the adjacent GUA triplet coding for Val at the aminoacyl (A) site. The interspin distances were measured between the two labels of mRNA analog attached to the first nucleotide of the peptidyl site bound codon and to the third nucleotide of the A site bound codon, in the absence/presence of second tRNA bound at the A site. The values of the obtained interspin distances agree with those calculated for available near-atomic structures of similar complexes of 40S and 80S ribosomes, showing that neither 60S subunit nor tRNA at the A site have a noticeable effect on arrangement of mRNA at the codon-anticodon interaction area. In addition, the shapes of distance distributions in four studied ribosomal complexes allowed conclusions on conformational flexibility of mRNA in these complexes. Overall, the results of this study are the first, to our knowledge, demonstration of double electron-electron resonance/pulsed electron-electron double resonance application for measurements of intramolecular distances in multicomponent supramolecular complexes involving intricate cellular machineries and for evaluating dynamic properties of ligands bound to these machineries.
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Affiliation(s)
- Alexey A Malygin
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia; Novosibirsk State University, Novosibirsk, Russia
| | - Dmitri M Graifer
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia; Novosibirsk State University, Novosibirsk, Russia
| | - Maria I Meschaninova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Aliya G Venyaminova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Olesya A Krumkacheva
- International Tomography Center SB RAS, Novosibirsk, Russia; Novosibirsk State University, Novosibirsk, Russia
| | - Matvey V Fedin
- International Tomography Center SB RAS, Novosibirsk, Russia; Novosibirsk State University, Novosibirsk, Russia.
| | - Galina G Karpova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia; Novosibirsk State University, Novosibirsk, Russia.
| | - Elena G Bagryanskaya
- N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, Novosibirsk, Russia; Novosibirsk State University, Novosibirsk, Russia.
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9
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Franck JM, Ding Y, Stone K, Qin PZ, Han S. Anomalously Rapid Hydration Water Diffusion Dynamics Near DNA Surfaces. J Am Chem Soc 2015; 137:12013-23. [PMID: 26256693 PMCID: PMC4656248 DOI: 10.1021/jacs.5b05813] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The emerging Overhauser effect dynamic nuclear polarization (ODNP) technique measures the translational mobility of water within the vicinity (5-15 Å) of preselected sites. The work presented here expands the capabilities of the ODNP technique and illuminates an important, previously unseen, property of the translational diffusion dynamics of water at the surface of DNA duplexes. We attach nitroxide radicals (i.e., spin labels) to multiple phosphate backbone positions of DNA duplexes, allowing ODNP to measure the hydration dynamics at select positions along the DNA surface. With a novel approach to ODNP analysis, we isolate the contributions of water molecules at these sites that undergo free translational diffusion from water molecules that either loosely bind to or exchange protons with the DNA. The results reveal that a significant population of water in a localized volume adjacent to the DNA surface exhibits fast, bulk-like characteristics and moves unusually rapidly compared to water found in similar probe volumes near protein and membrane surfaces. Control studies show that the observation of these characteristics are upheld even when the DNA duplex is tethered to streptavidin or the mobility of the nitroxides is altered. This implies that, as compared to protein or lipid surfaces, it is an intrinsic feature of the DNA duplex surface that it interacts only weakly with a significant fraction of the surface hydration water network. The displacement of this translationally mobile water is energetically less costly than that of more strongly bound water by up to several kBT and thus can lower the activation barrier for interactions involving the DNA surface.
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Affiliation(s)
- John M. Franck
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA
- National Biomedical Center for Advanced ESR Technology, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY
| | - Yuan Ding
- Department of Chemistry, University of Southern California, Los Angeles, CA
| | - Katherine Stone
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA
- Pacira Pharmaceuticals, Inc, San Diego, CA
| | - Peter Z. Qin
- Department of Chemistry, University of Southern California, Los Angeles, CA
| | - Songi Han
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA
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10
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Frost NR, McKeague M, Falcioni D, DeRosa MC. An in solution assay for interrogation of affinity and rational minimer design for small molecule-binding aptamers. Analyst 2015; 140:6643-51. [PMID: 26336657 DOI: 10.1039/c5an01075f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Aptamers are short single-stranded oligonucleotides that fold into unique three-dimensional structures, facilitating selective and high affinity binding to their cognate targets. It is not well understood how aptamer-target interactions affect regions of structure in an aptamer, particularly for small molecule targets where binding is often not accompanied by a dramatic change in structure. The DNase I footprinting assay is a classical molecular biology technique for studying DNA-protein interactions. The simplest application of this method permits identification of protein binding where DNase I digestion is inhibited. Here, we describe a novel variation of the classical DNase I assay to study aptamer-small molecule interactions. Given that DNase I preferentially cleaves duplex DNA over single-stranded DNA, we are able to identify regions of aptamer structure that are affected by small molecule target binding. Importantly, our method allows us to quantify these subtle effects, providing an in solution measurement of aptamer-target affinity. We applied this method to study aptamers that bind to the mycotoxin fumonisin B1, allowing the first identification of high affinity putative minimers for this important food contaminant. We confirmed the binding affinity of these minimers using a magnetic bead binding assay.
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Affiliation(s)
- Nadine R Frost
- Chemistry Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON, Canada K1S 5B6.
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11
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Nguyen PH, Popova AM, Hideg K, Qin PZ. A nucleotide-independent cyclic nitroxide label for monitoring segmental motions in nucleic acids. BMC BIOPHYSICS 2015; 8:6. [PMID: 25897395 PMCID: PMC4404236 DOI: 10.1186/s13628-015-0019-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 03/16/2015] [Indexed: 01/07/2023]
Abstract
Background Spin labels, which are chemically stable radicals attached at specific sites of a bio-molecule, enable investigations on structure and dynamics of proteins and nucleic acids using techniques such as site-directed spin labeling and paramagnetic NMR. Among spin labels developed, the class of rigid labels have limited or no independent motions between the radical bearing moiety and the target, and afford a number of advantages in measuring distances and monitoring local dynamics within the parent bio-molecule. However, a general method for attaching a rigid label to nucleic acids in a nucleotide-independent manner has not been reported. Results We developed an approach for installing a nearly rigid nitroxide spin label, designated as R5c, at a specific site of the nucleic acid backbone in a nucleotide-independent manner. The method uses a post-synthesis approach to covalently attach the nitroxide moiety in a cyclic fashion to phosphorothioate groups introduced at two consecutive nucleotides of the target strand. R5c-labeled nucleic acids are capable of pairing with their respective complementary strands, and the cyclic nature of R5c attachment significantly reduced independence motions of the label with respect to the parent duplex, although it may cause distortion of the local environment at the site of labeling. R5c yields enhanced sensitivity to the collective motions of the duplex, as demonstrated by its capability to reveal changes in collective motions of the substrate recognition duplex of the 120-kDa Tetrahymena group I ribozyme, which elude detection by a flexible label. Conclusions The cyclic R5c nitroxide can be efficiently attached to a target nucleic acid site using a post-synthetic coupling approach conducted under mild biochemical conditions, and serves as a viable label for experimental investigation of segmental motions in nucleic acids, including large folded RNAs. Electronic supplementary material The online version of this article (doi:10.1186/s13628-015-0019-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Phuong H Nguyen
- Department of Chemistry, University of Southern California, 840 Downey Way, Los Angeles, CA 90089-0744 USA ; Current Address: Bachem Americas, Torrance, CA 90505 USA
| | - Anna M Popova
- Department of Chemistry, University of Southern California, 840 Downey Way, Los Angeles, CA 90089-0744 USA ; Current Address: Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037 USA
| | - Kálmán Hideg
- Institute of Organic and Medicinal Chemistry, University of Pécs, Szigetic Strasse 12, Pécs, Hungary
| | - Peter Z Qin
- Department of Chemistry, University of Southern California, 840 Downey Way, Los Angeles, CA 90089-0744 USA
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12
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Zhao H, Chen J, Liu J, Han B. Transcriptome analysis reveals the oxidative stress response in Saccharomyces cerevisiae. RSC Adv 2015. [DOI: 10.1039/c4ra14600j] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A global regulatory network involving the response to the oxidation stress inSaccharomyces cerevisiaewas revealed in this study.
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Affiliation(s)
- Hongwei Zhao
- Beijing Laboratory for Food Quality and Safety
- College of Food Science and Nutritional Engineering
- China Agricultural University
- Beijing
- China
| | - Jingyu Chen
- Beijing Laboratory for Food Quality and Safety
- College of Food Science and Nutritional Engineering
- China Agricultural University
- Beijing
- China
| | - Jingjing Liu
- Beijing Laboratory for Food Quality and Safety
- College of Food Science and Nutritional Engineering
- China Agricultural University
- Beijing
- China
| | - Beizhong Han
- Beijing Laboratory for Food Quality and Safety
- College of Food Science and Nutritional Engineering
- China Agricultural University
- Beijing
- China
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13
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Tangprasertchai NS, Zhang X, Ding Y, Tham K, Rohs R, Haworth IS, Qin PZ. An Integrated Spin-Labeling/Computational-Modeling Approach for Mapping Global Structures of Nucleic Acids. Methods Enzymol 2015; 564:427-53. [PMID: 26477260 PMCID: PMC4641853 DOI: 10.1016/bs.mie.2015.07.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The technique of site-directed spin labeling (SDSL) provides unique information on biomolecules by monitoring the behavior of a stable radical tag (i.e., spin label) using electron paramagnetic resonance (EPR) spectroscopy. In this chapter, we describe an approach in which SDSL is integrated with computational modeling to map conformations of nucleic acids. This approach builds upon a SDSL tool kit previously developed and validated, which includes three components: (i) a nucleotide-independent nitroxide probe, designated as R5, which can be efficiently attached at defined sites within arbitrary nucleic acid sequences; (ii) inter-R5 distances in the nanometer range, measured via pulsed EPR; and (iii) an efficient program, called NASNOX, that computes inter-R5 distances on given nucleic acid structures. Following a general framework of data mining, our approach uses multiple sets of measured inter-R5 distances to retrieve "correct" all-atom models from a large ensemble of models. The pool of models can be generated independently without relying on the inter-R5 distances, thus allowing a large degree of flexibility in integrating the SDSL-measured distances with a modeling approach best suited for the specific system under investigation. As such, the integrative experimental/computational approach described here represents a hybrid method for determining all-atom models based on experimentally-derived distance measurements.
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Affiliation(s)
| | - Xiaojun Zhang
- Department of Chemistry, University of Southern California, Los Angeles, California, USA
| | - Yuan Ding
- Department of Chemistry, University of Southern California, Los Angeles, California, USA
| | - Kenneth Tham
- Department of Chemistry, University of Southern California, Los Angeles, California, USA
| | - Remo Rohs
- Department of Chemistry, University of Southern California, Los Angeles, California, USA,Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Ian S. Haworth
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California, USA
| | - Peter Z. Qin
- Department of Chemistry, University of Southern California, Los Angeles, California, USA,Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, Los Angeles, California, USA,Corresponding author:
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