1
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Kladova OA, Tyugashev TE, Miroshnikov AA, Novopashina DS, Kuznetsov NA, Kuznetsova AA. SNP-Associated Substitutions of Amino Acid Residues in the dNTP Selection Subdomain Decrease Polβ Polymerase Activity. Biomolecules 2024; 14:547. [PMID: 38785954 PMCID: PMC11117729 DOI: 10.3390/biom14050547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 04/18/2024] [Accepted: 04/30/2024] [Indexed: 05/25/2024] Open
Abstract
In the cell, DNA polymerase β (Polβ) is involved in many processes aimed at maintaining genome stability and is considered the main repair DNA polymerase participating in base excision repair (BER). Polβ can fill DNA gaps formed by other DNA repair enzymes. Single-nucleotide polymorphisms (SNPs) in the POLB gene can affect the enzymatic properties of the resulting protein, owing to possible amino acid substitutions. For many SNP-associated Polβ variants, an association with cancer, owing to changes in polymerase activity and fidelity, has been shown. In this work, kinetic analyses and molecular dynamics simulations were used to examine the activity of naturally occurring polymorphic variants G274R, G290C, and R333W. Previously, the amino acid substitutions at these positions have been found in various types of tumors, implying a specific role of Gly-274, Gly-290, and Arg-333 in Polβ functioning. All three polymorphic variants had reduced polymerase activity. Two substitutions-G274R and R333W-led to the almost complete disappearance of gap-filling and primer elongation activities, a decrease in the deoxynucleotide triphosphate-binding ability, and a lower polymerization constant, due to alterations of local contacts near the replaced amino acid residues. Thus, variants G274R, G290C, and R333W may be implicated in an elevated level of unrepaired DNA damage.
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Affiliation(s)
- Olga A. Kladova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.E.T.); (D.S.N.); (N.A.K.)
| | - Timofey E. Tyugashev
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.E.T.); (D.S.N.); (N.A.K.)
| | | | - Daria S. Novopashina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.E.T.); (D.S.N.); (N.A.K.)
| | - Nikita A. Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.E.T.); (D.S.N.); (N.A.K.)
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia;
| | - Aleksandra A. Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (T.E.T.); (D.S.N.); (N.A.K.)
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2
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Todisco M, Ding D, Szostak JW. Transient states during the annealing of mismatched and bulged oligonucleotides. Nucleic Acids Res 2024; 52:2174-2187. [PMID: 38348869 PMCID: PMC10954449 DOI: 10.1093/nar/gkae091] [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: 11/09/2023] [Revised: 01/19/2024] [Accepted: 01/29/2024] [Indexed: 03/22/2024] Open
Abstract
Oligonucleotide hybridization is crucial in various biological, prebiotic and nanotechnological processes, including gene regulation, non-enzymatic primer extension and DNA nanodevice assembly. Although extensive research has focused on the thermodynamics and kinetics of nucleic acid hybridization, the behavior of complex mixtures and the outcome of competition for target binding remain less well understood. In this study, we investigate the impact of mismatches and bulges in a 12 bp DNA or RNA duplex on its association (kon) and dissociation (koff) kinetics. We find that such defects have relatively small effects on the association kinetics, while the dissociation kinetics vary in a position-dependent manner by up to 6 orders of magnitude. Building upon this observation, we explored a competition scenario involving multiple oligonucleotides, and observed a transient low specificity of probe hybridization to fully versus partially complementary targets in solution. We characterize these long-lived metastable states and their evolution toward equilibrium, and show that sufficiently long-lived mis-paired duplexes can serve as substrates for prebiotically relevant chemical copying reactions. Our results suggest that transient low accuracy states may spontaneously emerge within all complex nucleic acid systems comprising a large enough number of competing strands, with potential repercussions for gene regulation in the realm of modern biology and the prebiotic preservation of genetic information.
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Affiliation(s)
- Marco Todisco
- Howard Hughes Medical Institute, Department of Chemistry, The University of Chicago, Chicago, IL 60637, USA
| | - Dian Ding
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
- Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, USA
| | - Jack W Szostak
- Howard Hughes Medical Institute, Department of Chemistry, The University of Chicago, Chicago, IL 60637, USA
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3
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Hoeher JE, Sande NE, Widom JR. Probing and perturbing riboswitch folding using a fluorescent base analogue. Photochem Photobiol 2024; 100:419-433. [PMID: 38098287 PMCID: PMC10950518 DOI: 10.1111/php.13896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 03/20/2024]
Abstract
Riboswitches are mRNA segments that regulate gene expression in response to ligand binding. The Class I preQ1 riboswitch consists of a stem-loop and an adenine-rich single-stranded tail ("L3"), which adopt a pseudoknot structure upon binding of the ligand preQ1 . We inserted 2-aminopurine (2-AP), a fluorescent analogue of adenine (A), into the riboswitch at six different positions within L3. Here, 2-AP functions both as a spectroscopic probe and as a "mutation" that reveals how alteration of specific A residues impacts the riboswitch. Using fluorescence and circular dichroism spectroscopy, we found that 2-AP decreases the affinity of the riboswitch for preQ1 at all labeling positions tested, although modified and unmodified variants undergo the same global conformational changes at sufficiently high preQ1 concentration. 2-AP substitution is most detrimental to ligand binding at sites proximal to the ligand-binding pocket, while distal labeling sites exhibit the largest impacts on the stability of the L3 domain in the absence of ligand. Insertion of multiple 2-AP residues does not induce significant additional disruptions. Our results show that interactions involving the A residues in L3 play a critical role in ligand recognition by the preQ1 riboswitch and that 2-AP substitution exerts complex and varied impacts on this riboswitch.
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Affiliation(s)
- Janson E. Hoeher
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR
| | - Natalie E. Sande
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR
| | - Julia R. Widom
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR
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4
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Yang F, Li S, Wu J, Liu S. 2-Aminopurine-based quencher-free DNA tweezers with fluorescence properties well tuned by surrounding bases. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2024; 16:576-582. [PMID: 38189219 DOI: 10.1039/d3ay01973j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Reversible structural changes in DNA nanomachines have great potential in the field of bioanalysis. Here, we demonstrate an assembly strategy for quencher-free and tunable DNA tweezers based on 2-aminopurine (2-AP), avoiding the tedious fluorescence labelling step. The conformational state of the tweezers could be controlled by specific oligonucleotides (fuel or anti-fuel). Taking advantage of the local environmental sensitivity of 2-AP, the structural changes of the tweezers were easily tracked, and multiple cyclic switching of the tweezers between the open and closed states was achieved. In addition, the influence of oligonucleotide structure on the fluorescence properties of 2-AP was deeply explored. We figured out that the fluorescence of 2-AP was highly quenched by the base-stacking of natural bases in DNA oligonucleotides. Moreover, by comprehensively regulating the type of bases surrounding the inserted 2-AP site, a sensitive fluorescence response towards dynamic change can be obtained. This principle of quencher-free nanodevices based on 2-AP provides a convenient method for monitoring the structural changes of DNA nanomachines.
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Affiliation(s)
- Fangfang Yang
- College of Chemistry and Chemical Engineering, Yantai University, 30 Qingquan Road, Yantai 264005, China.
| | - Shuang Li
- College of Chemistry and Chemical Engineering, Yantai University, 30 Qingquan Road, Yantai 264005, China.
| | - Jialiang Wu
- College of Chemistry and Chemical Engineering, Yantai University, 30 Qingquan Road, Yantai 264005, China.
| | - Shufeng Liu
- College of Chemistry and Chemical Engineering, Yantai University, 30 Qingquan Road, Yantai 264005, China.
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5
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Bakman AS, Boichenko SS, Kuznetsova AA, Ishchenko AA, Saparbaev M, Kuznetsov NA. Coordination between human DNA polymerase β and apurinic/apyrimidinic endonuclease 1 in the course of DNA repair. Biochimie 2024; 216:126-136. [PMID: 37806619 DOI: 10.1016/j.biochi.2023.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/08/2023] [Accepted: 10/06/2023] [Indexed: 10/10/2023]
Abstract
Coordination of enzymatic activities in the course of base excision repair (BER) is essential to ensure complete repair of damaged bases. Two major mechanisms underlying the coordination of BER are known today: the "passing the baton" model and a model of preassembled stable multiprotein repair complexes called "repairosomes." In this work, we aimed to elucidate the coordination between human apurinic/apyrimidinic (AP) endonuclease APE1 and DNA polymerase Polβ in BER through studying an impact of APE1 on Polβ-catalyzed nucleotide incorporation into different model substrates that mimic different single-strand break (SSB) intermediates arising along the BER pathway. It was found that APE1's impact on separate stages of Polβ's catalysis depends on the nature of a DNA substrate. In this complex, APE1 removed 3' blocking groups and corrected Polβ-catalyzed DNA synthesis in a coordinated manner. Our findings support the hypothesis that Polβ not only can displace APE1 from damaged DNA within the "passing the baton" model but also performs the gap-filling reaction in the ternary complex with APE1 according to the "repairosome" model. Taken together, our results provide new insights into coordination between APE1 and Polβ during the BER process.
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Affiliation(s)
- Artemiy S Bakman
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Prospekt Akad, Lavrentyeva, Novosibirsk, 630090, Russia
| | - Stanislav S Boichenko
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova Str., Novosibirsk, 630090, Russia
| | - Aleksandra A Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Prospekt Akad, Lavrentyeva, Novosibirsk, 630090, Russia
| | - Alexander A Ishchenko
- Group «Mechanisms of DNA Repair and Carcinogenesis», Gustave Roussy Cancer Campus, CNRS UMR9019, Université Paris-Saclay, 94805, Villejuif, France
| | - Murat Saparbaev
- Group «Mechanisms of DNA Repair and Carcinogenesis», Gustave Roussy Cancer Campus, CNRS UMR9019, Université Paris-Saclay, 94805, Villejuif, France
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Prospekt Akad, Lavrentyeva, Novosibirsk, 630090, Russia; Department of Natural Sciences, Novosibirsk State University, 2 Pirogova Str., Novosibirsk, 630090, Russia.
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6
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Russel NS, Kodali G, Stanley RJ, Narayanan M. Screening for Novel Fluorescent Nucleobase Analogues Using Computational and Experimental Methods: 2-Amino-6-chloro-8-vinylpurine (2A6Cl8VP) as a Case Study. J Phys Chem B 2023; 127:7858-7871. [PMID: 37698525 DOI: 10.1021/acs.jpcb.3c03618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
Novel fluorescent nucleic acid base analogues (FBAs) with improved optical properties are needed in a variety of biological applications. 2-Amino-6-chloro-8-vinylpurine (2A6Cl8VP) is structural analogue of two existing highly fluorescent FBAs, 2-aminopurine (2AP) and 8-vinyladenine (8VA), and can therefore be expected to have similar base pairing as well as better optical properties compared to its counterparts. In order to determine the absorption and fluorescence properties of 2A6Cl8VP, as a first step, we used TD-DFT calculations and the polarizable continuum model for simulating the solvents and computationally predicted absorption and fluorescence maxima. To test the computational predictions, we also synthesized 2A6Cl8VP and measured its UV/vis absorbance, fluorescence emission, and fluorescence lifetime. The computationally predicted absorbance and fluorescence maxima of 2A6Cl8VP are in reasonable agreement to the experimental values and are significantly redshifted compared to 2AP and 8VA, allowing for its specific excitation. The fluorescence quantum yield of 2A6Cl8VP, however, is significantly lower than those of 2AP and 8VA. Overall, 2A6Cl8VP is a novel fluorescent nucleobase analogue, which can be useful in studying structural, biophysical, and biochemical applications.
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Affiliation(s)
- Nadim Shahriar Russel
- Department of Chemistry, Temple University, 1901 N. Broad Street, Philadelphia, Pennsylvania 19122, United States
| | - Goutham Kodali
- GlowDNA LLC., Malvern, Pennsylvania 19355, United States
| | - Robert J Stanley
- Department of Chemistry, Temple University, 1901 N. Broad Street, Philadelphia, Pennsylvania 19122, United States
| | - Madhavan Narayanan
- Department of Physical Sciences, Benedictine University, 5700 College Rd, Lisle, Illinois 60532, United States
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7
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Monari A, Burger A, Dumont E. Rationalizing the environment-dependent photophysical behavior of a DNA luminescent probe by classical and non-adiabatic molecular dynamics simulations. Photochem Photobiol Sci 2023; 22:2081-2092. [PMID: 37166569 DOI: 10.1007/s43630-023-00431-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 04/26/2023] [Indexed: 05/12/2023]
Abstract
Environment-sensitive fluorescent nucleoside analogs are of utmost importance to investigate the structure of nucleic acids, their intrinsic flexibility, and sequence-specific DNA- and RNA-binding proteins. The latter play indeed a key role in transcription, translation as well as in the regulation of RNA stability, localization and turnover, and many other cellular processes. The sensitivity of the embedded fluorophore to polarity, hydration, and base stacking is clearly dependent on the specific excited-state relaxation mechanism and can be rationalized combining experimental and computational techniques. In this work, we elucidate the mechanisms leading to the population of the triplet state manifold for a versatile nucleobase surrogate, namely the 2-thienyl-3-hydroxychromone in gas phase, owing to non-adiabatic molecular dynamics simulations. Furthermore, we analyze its behavior in the B-DNA environment via classical molecular dynamics simulations, which evidence a rapid extrusion of the adenine facing the 2-thienyl-3-hydroxychromone nucleobase surrogate. Our simulations provide new insights into the dynamics of this family of chromophores, which could give rise to an integrated view and a fine tuning of their photochemistry, and namely the role of excited-state intramolecular proton transfer for the rational design of the next generation of fluorescent nucleoside analogs.
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Affiliation(s)
- Antonio Monari
- Université Paris Cité and CNRS, ITODYS, 75006, Paris, France.
| | - Alain Burger
- Institut de Chimie de Nice, UMR 7272, Université Côte d'Azur, CNRS, 06108, Nice, France
| | - Elise Dumont
- Institut de Chimie de Nice, UMR 7272, Université Côte d'Azur, CNRS, 06108, Nice, France.
- Institut Universitaire de France, 5 Rue Descartes, 75005, Paris, France.
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8
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Botto M, Murthy S, Lamers MH. High-Throughput Exonuclease Assay Based on the Fluorescent Base Analogue 2-Aminopurine. ACS OMEGA 2023; 8:8285-8292. [PMID: 36910963 PMCID: PMC9996622 DOI: 10.1021/acsomega.2c06577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
Exonucleases are essential enzymes that remove nucleotides from free DNA ends during DNA replication, DNA repair, and telomere maintenance. Due to their essential role, they are potential targets for novel anticancer and antimicrobial drugs but have so far been little exploited. Here, we present a simple and versatile real-time exonuclease assay based on 2-aminopurine, an intrinsically fluorescent nucleotide that is quenched by neighboring bases when embedded in DNA. We show that our assay is applicable to different eukaryotic and bacterial exonucleases acting on both 3' and 5' DNA ends over a wide range of protein activities and suitable for a high-throughput inhibitor screening campaign. Using our assay, we discover a novel inhibitor of the Mycobacterium tuberculosis PHP-exonuclease that is part of the replicative DNA polymerase DnaE1. Hence, our novel assay will be a useful tool for high-throughput screening for novel exonuclease inhibitors that may interfere with DNA replication or DNA maintenance.
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9
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Li Y, Liu K, Wang B, Liu Z, Yang C, Wang J, Ma X, Li H, Sun C. Engineering DNAzyme strategies for fluorescent detection of lead ions based on RNA cleavage-propelled signal amplification. JOURNAL OF HAZARDOUS MATERIALS 2022; 440:129712. [PMID: 35952430 DOI: 10.1016/j.jhazmat.2022.129712] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 07/21/2022] [Accepted: 08/02/2022] [Indexed: 05/07/2023]
Abstract
Based on the high recognition ability and flexible programmability of GR5 DNAzyme, two fluorescent biosensors were engineered for amplified detection of Pb2+ via incorporating Ti3C2TX MXenes and embedding 2-aminopurine (2-AP), respectively. The quencher-required approach relied on the DNA affinity and fluorescence quenching ability of Ti3C2TX MXenes. Benefiting from the low background signal modulated by Ti3C2TX MXenes, the sensitive determination of Pb2+ was achieved in the linear range of 0.2-10 ng mL-1 with the limit of detection (LOD) of 0.05 ng mL-1. The quencher-free approach combined the fluorescent trait of 2-AP embedded in DNA structure, and the RNA cleavage-propelled digestion process of Exonuclease I (Exo I) for signal amplification, indicating the sensitive detection of Pb2+ with the LOD as low as 0.02 ng mL-1 in the linear range of 0.1-10 ng mL-1. Both DNAzyme assays exhibited simple procedures, favorable specificity, rapid analysis, and satisfactory application in standard reference materials (lead in drinking water) and spiked water samples. The two fluorescent biosensors established in this work would not only provide theoretic fundament for DNA adsorption of Ti3C2TX MXenes and the design of 2-AP-embedded DNAzyme assays, but also hold a great potential for on-site monitoring of lead pollution in water samples.
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Affiliation(s)
- Ying Li
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China
| | - Kai Liu
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China
| | - Boxu Wang
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China
| | - Zheng Liu
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China
| | - Chuanyu Yang
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China
| | - Junyang Wang
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China
| | - Xinyue Ma
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China
| | - Hongxia Li
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China.
| | - Chunyan Sun
- Department of Food Quality and Safety, Jilin University, Changchun 130062, China.
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10
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Wang J, Shimada N, Maruyama A. Cationic Copolymer-Augmented DNA Hybridization Chain Reaction. ACS APPLIED MATERIALS & INTERFACES 2022; 14:39396-39403. [PMID: 35975327 DOI: 10.1021/acsami.2c11548] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Various DNA assembly techniques and structures have emerged with the continuous progress of DNA nanotechnology. DNA hybridization chain reaction (HCR) is a representative example owing to isothermal and enzyme-free features. However, HCR is time consuming and is inhibited by nucleases present in biological samples. Herein, we demonstrated that a cationic copolymer, poly(l-lysine)-graft-dextran (PLL-g-Dex), significantly facilitated HCR and increased its initiator sensitivity by 40-fold. PLL-g-Dex promoted the generation of HCR products with high molecular weight by accelerating the initiation and the subsequent growth steps of HCR. Moreover, PLL-g-Dex protected the HCR system from nucleases, permitting HCR in the presence of serum components. Addition of PLL-g-Dex is a universal and efficient strategy that does not require optimization of the reactor setup or DNA sequences, thus laying a solid foundation for the wider application of HCR.
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Affiliation(s)
- Jun Wang
- Department of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259 B-57, Midori, Yokohama 226-8501, Japan
| | - Naohiko Shimada
- Department of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259 B-57, Midori, Yokohama 226-8501, Japan
| | - Atsushi Maruyama
- Department of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259 B-57, Midori, Yokohama 226-8501, Japan
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11
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Dziuba D. Environmentally sensitive fluorescent nucleoside analogues as probes for nucleic acid - protein interactions: molecular design and biosensing applications. Methods Appl Fluoresc 2022; 10. [PMID: 35738250 DOI: 10.1088/2050-6120/ac7bd8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 06/23/2022] [Indexed: 11/12/2022]
Abstract
Fluorescent nucleoside analogues (FNAs) are indispensable in studying the interactions of nucleic acids with nucleic acid-binding proteins. By replacing one of the poorly emissive natural nucleosides, FNAs enable real-time optical monitoring of the binding interactions in solutions, under physiologically relevant conditions, with high sensitivity. Besides that, FNAs are widely used to probe conformational dynamics of biomolecular complexes using time-resolved fluorescence methods. Because of that, FNAs are tools of high utility for fundamental biological research, with potential applications in molecular diagnostics and drug discovery. Here I review the structural and physical factors that can be used for the conversion of the molecular binding events into a detectable fluorescence output. Typical environmentally sensitive FNAs, their properties and applications, and future challenges in the field are discussed.
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Affiliation(s)
- Dmytro Dziuba
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 Route du Rhin, Illkirch-Graffenstaden, Grand Est, 67401, FRANCE
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12
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Paudel BP, Xu ZQ, Jergic S, Oakley AJ, Sharma N, Brown SHJ, Bouwer JC, Lewis PJ, Dixon NE, van Oijen AM, Ghodke H. Mechanism of transcription modulation by the transcription-repair coupling factor. Nucleic Acids Res 2022; 50:5688-5712. [PMID: 35641110 PMCID: PMC9177983 DOI: 10.1093/nar/gkac449] [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: 02/19/2022] [Revised: 05/06/2022] [Accepted: 05/13/2022] [Indexed: 11/27/2022] Open
Abstract
Elongation by RNA polymerase is dynamically modulated by accessory factors. The transcription-repair coupling factor (TRCF) recognizes paused/stalled RNAPs and either rescues transcription or initiates transcription termination. Precisely how TRCFs choose to execute either outcome remains unclear. With Escherichia coli as a model, we used single-molecule assays to study dynamic modulation of elongation by Mfd, the bacterial TRCF. We found that nucleotide-bound Mfd converts the elongation complex (EC) into a catalytically poised state, presenting the EC with an opportunity to restart transcription. After long-lived residence in this catalytically poised state, ATP hydrolysis by Mfd remodels the EC through an irreversible process leading to loss of the RNA transcript. Further, biophysical studies revealed that the motor domain of Mfd binds and partially melts DNA containing a template strand overhang. The results explain pathway choice determining the fate of the EC and provide a molecular mechanism for transcription modulation by TRCF.
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Affiliation(s)
- Bishnu P Paudel
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Zhi-Qiang Xu
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Slobodan Jergic
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Aaron J Oakley
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Nischal Sharma
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Simon H J Brown
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia.,ARC Industrial Transformation Training Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW 2522, Australia
| | - James C Bouwer
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia.,ARC Industrial Transformation Training Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Peter J Lewis
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Nicholas E Dixon
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia.,ARC Industrial Transformation Training Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Antoine M van Oijen
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia.,ARC Industrial Transformation Training Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Harshad Ghodke
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
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13
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Thienoguanosine, a unique non-perturbing reporter for investigating rotational dynamics of DNA duplexes and their complexes with proteins. Int J Biol Macromol 2022; 213:210-225. [DOI: 10.1016/j.ijbiomac.2022.05.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/02/2022] [Accepted: 05/23/2022] [Indexed: 11/05/2022]
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14
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Abstract
![]()
We
explore the process of base-flipping for four central bases,
adenine, guanine, cytosine, and thymine, in a deoxyribonucleic acid
(DNA) duplex using the energy landscape perspective. NMR imino-proton
exchange and fluorescence correlation spectroscopy studies have been
used in previous experiments to obtain lifetimes for bases in paired
and extrahelical states. However, the difference of almost 4 orders
of magnitude in the base-flipping rates obtained by the two methods
implies that they are exploring different pathways and possibly different
open states. Our results support the previous suggestion that minor
groove opening may be favored by distortions in the DNA backbone and
reveal links between sequence effects and the direction of opening,
i.e., whether the base flips toward the major or the minor groove
side. In particular, base flipping along the minor groove pathway
was found to align toward the 5′ side of the backbone. We find
that bases align toward the 3′ side of the backbone when flipping
along the major groove pathway. However, in some cases for cytosine
and thymine, the base flipping along the major groove pathway also
aligns toward the 5′ side. The sequence effect may be caused
by the polar interactions between the flipping-base and its neighboring
bases on either of the strands. For guanine flipping toward the minor
groove side, we find that the equilibrium constant for opening is
large compared to flipping via the major groove. We find that the
estimated rates of base opening, and hence the lifetimes of the closed
state, obtained for thymine flipping through small and large angles
along the major groove differ by 6 orders of magnitude, whereas for
thymine flipping through small angles along the minor groove and large
angles along the major groove, the rates differ by 3 orders of magnitude.
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Affiliation(s)
- Nicy
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, U.K
| | - Debayan Chakraborty
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - David J. Wales
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, U.K
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15
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Determination of two-photon absorption in nucleobase analogues: a QR-DFT perspective. Photochem Photobiol Sci 2022; 21:529-543. [PMID: 35179700 DOI: 10.1007/s43630-022-00182-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 01/27/2022] [Indexed: 10/19/2022]
Abstract
With the prevalence of fluorescence spectroscopy in biological systems, and the benefits of two-photon absorption techniques, presented here is an assessment of the two-photon accessibility of modern fluorescent nucleobase analogues utilising quadratic response DFT. Due to the complex environment experienced by these nucleobases, the two-photon spectra of each analogue has been assessed in the presence of both [Formula: see text]-stacked and hydrogen-bonding interactions involving the canonical nucleobases. Findings suggest that the [Formula: see text]-stacking environment provides a more significant effect on the spectra of the analogues studies than a hydrogen-bonding environment; analogue structures presenting high two-photon cross-section values for one or more states coincide with polycyclic extensions to preserved canonical base structure, as observed in the qA family of analogues, while analogue structures more closely resembling the structure of the base in question present a much more muted spectra in comparison. Results from this investigation have also allowed for the derivation of a number of design rules for the development of potential, two-photon specific, analogues for future use in both imaging and potential photochemical activation.
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16
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Evans GW, Craggs T, Kapanidis AN. The Rate-limiting Step of DNA Synthesis by DNA Polymerase Occurs in the Fingers-closed Conformation. J Mol Biol 2022; 434:167410. [PMID: 34929202 PMCID: PMC8783057 DOI: 10.1016/j.jmb.2021.167410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/22/2021] [Accepted: 12/12/2021] [Indexed: 12/03/2022]
Abstract
DNA polymerases maintain genomic integrity by copying DNA with high fidelity, part of which relies on the polymerase fingers opening-closing transition, a series of conformational changes during the DNA synthesis reaction cycle. Fingers opening and closing has been challenging to study, mainly due to the need to synchronise molecular ensembles. We previously studied fingers opening-closing on single polymerase-DNA complexes using single-molecule FRET; however, our work was limited to pre-chemistry reaction steps. Here, we advance our analysis to extensible substrates, and observe DNA polymerase (Pol) conformational changes across the entire DNA polymerisation reaction in real-time, gaining direct access to an elusive post-chemistry step rate-limiting for DNA synthesis. Our results showed that Pol adopts the fingers-closed conformation during polymerisation, and that the post-chemistry rate-limiting step occurs in the fingers-closed conformation. We found that fingers-opening in the Pol-DNA binary complex in the absence of polymerisation is slow (∼5.3 s-1), and comparable to the rate of fingers-opening after polymerisation (3.4 s-1); this indicates that the fingers-opening step itself could be largely responsible for the slow post-chemistry step, with the residual rate potentially accounted for by pyrophosphase release. We also observed that DNA chain-termination of the 3' end of the primer increases substantially the rate of fingers-opening in the Pol-DNA binary complex (5.3 → 29 s-1), demonstrating that the 3'-OH residue is important for the kinetics of fingers conformational changes. Our observations offer mechanistic insight and tools to offer mechanistic insight for all nucleic acid polymerases.
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Affiliation(s)
- Geraint W Evans
- Department of Physics and Biological Physics Research Group, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom. https://twitter.com/geraintwe
| | - Timothy Craggs
- Department of Physics and Biological Physics Research Group, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom; Sheffield Institute for Nucleic Acids, Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, United Kingdom. https://twitter.com/Craggs_Lab
| | - Achillefs N Kapanidis
- Department of Physics and Biological Physics Research Group, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
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17
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Ying N, Wang Y, Song X, Yang L, Qin B, Wu Y, Fang W. Lateral flow colorimetric biosensor for detection of Vibrio parahaemolyticus based on hybridization chain reaction and aptamer. Mikrochim Acta 2021; 188:381. [PMID: 34654957 DOI: 10.1007/s00604-021-05031-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 09/17/2021] [Indexed: 10/20/2022]
Abstract
Vibrio parahaemolyticus (V. parahaemolyticus) is the causative agent for acute hepatopancreatic necrosis disease (AHPND) of shrimp, and it is also a common seafood-borne pathogen for humans. Rapid and accurate identification of V. parahaemolyticus is helpful to diagnose the AHPND and ensure food safety. Common detection methods suffer the deficiency of time-consuming and complexed operation. Based on the increased development of aptamer and our previous study, a new detection assay of V. parahaemolyticus was introduced, in which the aptamer combined with magnetic nanoparticles (MNPs) was the recognizer, hybridization chain reaction (HCR) was the signal amplifier, and lateral flow nucleotide biosensor (LFNB) was the signal exporter. The assay possessed high specificity of distinguishing the target with other bacteria, and the calculated limit of detection was 2.6 × 103 cells. Furthermore, the whole process just needs 67 min, free of thermocycle instruments and signal readout instruments, which means it is suitable for low-resource laboratories or districts.
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Affiliation(s)
- Na Ying
- East China Sea Fisheries Research Institute, China Academy of Fishery Sciences, Shanghai, 200090, China
| | - Yuan Wang
- East China Sea Fisheries Research Institute, China Academy of Fishery Sciences, Shanghai, 200090, China
| | - Xuefeng Song
- East China Sea Fisheries Research Institute, China Academy of Fishery Sciences, Shanghai, 200090, China
| | - Liguo Yang
- East China Sea Fisheries Research Institute, China Academy of Fishery Sciences, Shanghai, 200090, China
| | - Bo Qin
- East China Sea Fisheries Research Institute, China Academy of Fishery Sciences, Shanghai, 200090, China
| | - Yanqing Wu
- East China Sea Fisheries Research Institute, China Academy of Fishery Sciences, Shanghai, 200090, China
| | - Wenhong Fang
- East China Sea Fisheries Research Institute, China Academy of Fishery Sciences, Shanghai, 200090, China.
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18
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Malina J, Kostrhunova H, Scott P, Brabec V. Fe II Metallohelices Stabilize DNA G-Quadruplexes and Downregulate the Expression of G-Quadruplex-Regulated Oncogenes. Chemistry 2021; 27:11682-11692. [PMID: 34048082 DOI: 10.1002/chem.202101388] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Indexed: 12/15/2022]
Abstract
DNA G-quadruplexes (G4s) have been identified within the promoter regions of many proto-oncogenes. Thus, G4s represent attractive targets for cancer therapy, and the design and development of new drugs as G4 binders is a very active field of medicinal chemistry. Here, molecular biophysics and biology methods were employed to investigate the interaction of chiral metallohelices with a series of four DNA G4s (hTelo, c-myc, c-kit1, c-kit2) that are formed by the human telomeric sequence (hTelo) and in the promoter regions of c-MYC and c-KIT proto-oncogenes. We show that the investigated water-compatible, optically pure metallohelices, which are made by self-assembly of simple nonpeptidic organic components around FeII ions and exhibit bioactivity emulating the natural systems, bind with high affinity to G4 DNA and much lower affinity to duplex DNA. Notably, both enantiomers of a metallohelix containing a m-xylenyl bridge (5 b) were found to effectively inhibit primer elongation catalyzed by Taq DNA polymerase by stabilizing G4 structures formed in the template strands containing c-myc and c-kit2 G4-forming sequences. Moreover, both enantiomers of 5 b downregulated the expression of c-MYC and c-KIT oncogenes in human embryonic kidney cells at mRNA and protein levels. As metallohelices also bind alternative nucleic acid structures, they hold promise as potential multitargeted drugs.
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Affiliation(s)
- Jaroslav Malina
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
| | - Hana Kostrhunova
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
| | - Peter Scott
- Department of Chemistry, University of Warwick, Coventry, CV4 7AL, UK
| | - Viktor Brabec
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
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19
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Dziuba D, Didier P, Ciaco S, Barth A, Seidel CAM, Mély Y. Fundamental photophysics of isomorphic and expanded fluorescent nucleoside analogues. Chem Soc Rev 2021; 50:7062-7107. [PMID: 33956014 DOI: 10.1039/d1cs00194a] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Fluorescent nucleoside analogues (FNAs) are structurally diverse mimics of the natural essentially non-fluorescent nucleosides which have found numerous applications in probing the structure and dynamics of nucleic acids as well as their interactions with various biomolecules. In order to minimize disturbance in the labelled nucleic acid sequences, the FNA chromophoric groups should resemble the natural nucleobases in size and hydrogen-bonding patterns. Isomorphic and expanded FNAs are the two groups that best meet the criteria of non-perturbing fluorescent labels for DNA and RNA. Significant progress has been made over the past decades in understanding the fundamental photophysics that governs the spectroscopic and environmentally sensitive properties of these FNAs. Herein, we review recent advances in the spectroscopic and computational studies of selected isomorphic and expanded FNAs. We also show how this information can be used as a rational basis to design new FNAs, select appropriate sequences for optimal spectroscopic response and interpret fluorescence data in FNA applications.
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Affiliation(s)
- Dmytro Dziuba
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, Université de Strasbourg, 74 route du Rhin, 67401 Illkirch, France.
| | - Pascal Didier
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, Université de Strasbourg, 74 route du Rhin, 67401 Illkirch, France.
| | - Stefano Ciaco
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, Université de Strasbourg, 74 route du Rhin, 67401 Illkirch, France. and Department of Biotechnology, Chemistry and Pharmacy, University of Siena, via Aldo Moro 2, 53100 Siena, Italy
| | - Anders Barth
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Claus A M Seidel
- Institut für Physikalische Chemie, Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Yves Mély
- Laboratoire de Bioimagerie et Pathologies, UMR 7021, Université de Strasbourg, 74 route du Rhin, 67401 Illkirch, France.
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20
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Bull GD, Thompson KC. The oxidation of guanine by photoionized 2-aminopurine. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY 2021. [DOI: 10.1016/j.jpap.2021.100025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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21
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Kuznetsova AA, Gavrilova AA, Novopashina DS, Fedorova OS, Kuznetsov NA. Mutational and Kinetic Analysis of APE1 Endoribonuclease Activity. Mol Biol 2021; 55:211-224. [PMID: 33948042 PMCID: PMC8083922 DOI: 10.1134/s0026893321020102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/09/2020] [Accepted: 11/09/2020] [Indexed: 12/20/2022]
Abstract
Human apurinic/apyrimidinic endonuclease 1 (APE1) participates in the DNA repair system. It is believed that the main biological function of APE1 is Mg2+-dependent hydrolysis of AP-sites in DNA. On the base of structural data, kinetic studies, and mutation analysis, the key stages of APE1 interaction with damaged DNA were established. It has been shown recently that APE1 can act as an endoribonuclease that catalyzes mRNA hydrolysis at certain pyrimidine–purine sites and thus controls the level of certain transcripts. In addition, the presence of Mg2+ ions was shown to be not required for the endoribonuclease activity of APE1, in contrast to the AP-endonuclease activity. This indicates differences in mechanisms of APE1 catalysis on RNA and DNA substrates, but the reasons for these differences remain unclear. Here, the analysis of endoribonuclease hydrolysis of model RNA substrates with wild type APE1 enzyme and its mutant forms Y171F, R177F, R181A, D210N, N212A, T268D, M270A, and D308A, was performed. It was shown that mutation of Asn212, Asp210, and Tyr171 residues leads to the decrease of AP-endonuclease activity while endoribonuclease activity is retained. Also, T268D and M270A APE1 mutants lose specificity to pyrimidine–purine sequences. R177F and R181A did not show a significant decrease in enzyme activity, whereas D308A demonstrated a decrease of endoribonuclease activity.
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Affiliation(s)
- A A Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - A A Gavrilova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia.,Novosibirsk National Research State University, 630090 Novosibirsk, Russia
| | - D S Novopashina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - O S Fedorova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - N A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia
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22
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Camel BR, Jose D, Meze K, Dang A, von Hippel PH. Mapping DNA conformations and interactions within the binding cleft of bacteriophage T4 single-stranded DNA binding protein (gp32) at single nucleotide resolution. Nucleic Acids Res 2021; 49:916-927. [PMID: 33367802 PMCID: PMC7826291 DOI: 10.1093/nar/gkaa1230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/28/2020] [Accepted: 12/07/2020] [Indexed: 11/29/2022] Open
Abstract
In this study, we use single-stranded DNA (oligo-dT) lattices that have been position-specifically labeled with monomer or dimer 2-aminopurine (2-AP) probes to map the local interactions of the DNA bases with the nucleic acid binding cleft of gp32, the single-stranded binding (ssb) protein of bacteriophage T4. Three complementary spectroscopic approaches are used to characterize these local interactions of the probes with nearby nucleotide bases and amino acid residues at varying levels of effective protein binding cooperativity, as manipulated by changing lattice length. These include: (i) examining local quenching and enhancing effects on the fluorescence spectra of monomer 2-AP probes at each position within the cleft; (ii) using acrylamide as a dynamic-quenching additive to measure solvent access to monomer 2-AP probes at each ssDNA position; and (iii) employing circular dichroism spectra to characterize changes in exciton coupling within 2-AP dimer probes at specific ssDNA positions within the protein cleft. The results are interpreted in part by what we know about the topology of the binding cleft from crystallographic studies of the DNA binding domain of gp32 and provide additional insights into how gp32 can manipulate the ssDNA chain at various steps of DNA replication and other processes of genome expression.
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Affiliation(s)
- Benjamin R Camel
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
| | - Davis Jose
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA.,Department of Chemistry and Physics, Monmouth University, West Long Branch, NJ 07764, USA
| | - Katarina Meze
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
| | - Anson Dang
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
| | - Peter H von Hippel
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, USA
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23
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Iakovlev DA, Alekseeva IV, Kuznetsov NA, Fedorova OS. Role of Arg243 and His239 Residues in the Recognition of Damaged Nucleotides by Human Uracil-DNA Glycosylase SMUG1. BIOCHEMISTRY (MOSCOW) 2021; 85:594-603. [PMID: 32571189 DOI: 10.1134/s0006297920050089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Human uracil-DNA glycosylase SMUG1 removes uracil residues and some other noncanonical or damaged bases from DNA. Despite the functional importance of this enzyme, its X-ray structure is still unavailable. Previously, we performed homology modeling of human SMUG1 structure and suggested the roles of some amino acid residues in the recognition of damaged nucleotides and their removal from DNA. In this study, we investigated the kinetics of conformational transitions in the protein and in various DNA substrates during enzymatic catalysis using the stopped-flow method based on changes in the fluorescence intensity of enzyme's tryptophan residues and 2-aminopurine in DNA or fluorescence resonance energy transfer (FRET) between fluorophores in DNA. The kinetic mechanism of interactions between reaction intermediates was identified, and kinetic parameters of the intermediate formation and dissociation were calculated. The obtained data help in elucidating the functions of His239 and Arg243 residues in the recognition and removal of damaged nucleotides by SMUG1.
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Affiliation(s)
- D A Iakovlev
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.,Novosibirsk State University, Department of Natural Sciences, Novosibirsk, 630090, Russia
| | - I V Alekseeva
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia
| | - N A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.
| | - O S Fedorova
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.
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24
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Sinha K, Sharma P, Som Chaudhury S, Das Mukhopadhyay C, Ruidas B. Species detection using probe technology. FOOD TOXICOLOGY AND FORENSICS 2021:313-346. [DOI: 10.1016/b978-0-12-822360-4.00012-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
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25
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Abstract
Labeling of nucleic acids is required for many studies aiming to elucidate their functions and dynamics in vitro and in cells. Out of the numerous labeling concepts that have been devised, covalent labeling provides the most stable linkage, an unrivaled choice of small and highly fluorescent labels and - thanks to recent advances in click chemistry - an incredible versatility. Depending on the approach, site-, sequence- and cell-specificity can be achieved. DNA and RNA labeling are rapidly developing fields that bring together multiple areas of research: on the one hand, synthetic and biophysical chemists develop new fluorescent labels and isomorphic nucleobases as well as faster and more selective bioorthogonal reactions. On the other hand, the number of enzymes that can be harnessed for post-synthetic and site-specific labeling of nucleic acids has increased significantly. Together with protein engineering and genetic manipulation of cells, intracellular and cell-specific labeling has become possible. In this review, we provide a structured overview of covalent labeling approaches for nucleic acids and highlight notable developments, in particular recent examples. The majority of this review will focus on fluorescent labeling; however, the principles can often be readily applied to other labels. We will start with entirely chemical approaches, followed by chemo-enzymatic strategies and ribozymes, and finish with metabolic labeling of nucleic acids. Each section is subdivided into direct (or one-step) and two-step labeling approaches and will start with DNA before treating RNA.
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Affiliation(s)
- Nils Klöcker
- Institute of Biochemistry, University of Muenster, Corrensstraße 36, D-48149 Münster, Germany.
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26
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Kuznetsova AA, Fedorova OS, Kuznetsov NA. Lesion Recognition and Cleavage of Damage-Containing Quadruplexes and Bulged Structures by DNA Glycosylases. Front Cell Dev Biol 2020; 8:595687. [PMID: 33330484 PMCID: PMC7734321 DOI: 10.3389/fcell.2020.595687] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 11/10/2020] [Indexed: 12/22/2022] Open
Abstract
Human telomeres as well as more than 40% of human genes near the promoter regions have been found to contain the sequence that may form a G-quadruplex structure. Other non-canonical DNA structures comprising bulges, hairpins, or bubbles may have a functionally important role during transcription, replication, or recombination. The guanine-rich regions of DNA are hotspots of oxidation that forms 7,8-dihydro-8-oxoguanine, thymine glycol, and abasic sites: the lesions that are handled by the base excision repair pathway. Nonetheless, the features of DNA repair processes in non-canonical DNA structures are still poorly understood. Therefore, in this work, a comparative analysis of the efficiency of the removal of a damaged nucleotide from various G-quadruplexes and bulged structures was performed using endonuclease VIII-like 1 (NEIL1), human 8-oxoguanine-DNA glycosylase (OGG1), endonuclease III (NTH1), and prokaryotic formamidopyrimidine-DNA glycosylase (Fpg), and endonuclease VIII (Nei). All the tested enzymes were able to cleave damage-containing bulged DNA structures, indicating their important role in the repair process when single-stranded DNA and intermediate non–B-form structures such as bubbles and bulges are formed. Nevertheless, our results suggest that the ability to cleave damaged quadruplexes is an intrinsic feature of members of the H2tH structural family, suggesting that these enzymes can participate in the modulation of processes controlled by the formation of quadruplex structures in genomic DNA.
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Affiliation(s)
| | - Olga S Fedorova
- Institute of Chemical Biology and Fundamental Medicine of SB RAS, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine of SB RAS, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
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27
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Hrabina O, Malina J, Scott P, Brabec V. Cationic Fe
II
Triplex‐Forming Metallohelices as DNA Bulge Binders. Chemistry 2020; 26:16554-16562. [DOI: 10.1002/chem.202004060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Ondrej Hrabina
- Institute of Biophysics Czech Academy of Sciences Kralovopolska 135 61265 Brno Czech Republic
| | - Jaroslav Malina
- Institute of Biophysics Czech Academy of Sciences Kralovopolska 135 61265 Brno Czech Republic
| | - Peter Scott
- Department of Chemistry University of Warwick Gibbet Hill Road Coventry CV4 7AL UK
| | - Viktor Brabec
- Institute of Biophysics Czech Academy of Sciences Kralovopolska 135 61265 Brno Czech Republic
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28
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Malina J, Scott P, Brabec V. Stabilization of human telomeric RNA G-quadruplex by the water-compatible optically pure and biologically-active metallohelices. Sci Rep 2020; 10:14543. [PMID: 32884069 PMCID: PMC7471899 DOI: 10.1038/s41598-020-71429-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 08/07/2020] [Indexed: 02/06/2023] Open
Abstract
RNA G-quadruplexes have been suggested to play key roles in fundamental biological processes and are linked to human diseases. Thus, they also represent good potential therapeutic targets. Here, we describe, using the methods of molecular biophysics, interactions of a series of biologically-active supramolecular cationic metallohelices with human telomeric RNA G-quadruplex. We demonstrate that the investigated metallohelices bind with a high affinity to human telomeric RNA G-quadruplex and that their binding selectivity considerably differs depending on the dimensions and overall shape of the metallohelices. Additionally, the investigated metallohelices inhibit DNA synthesis on the RNA template containing four repeats of the human telomeric sequence by stabilizing the RNA G-quadruplex structure. Collectively, the results of this study suggest that stabilization of RNA sequences capable of G-quadruplex formation by metallohelices investigated in this work might contribute to the mechanism of their biological activity.
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Affiliation(s)
- Jaroslav Malina
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic
| | - Peter Scott
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | - Viktor Brabec
- Institute of Biophysics, Czech Academy of Sciences, Kralovopolska 135, 61265, Brno, Czech Republic.
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29
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The role of active-site amino acid residues in the cleavage of DNA and RNA substrates by human apurinic/apyrimidinic endonuclease APE1. Biochim Biophys Acta Gen Subj 2020; 1864:129718. [PMID: 32858086 DOI: 10.1016/j.bbagen.2020.129718] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/10/2020] [Accepted: 08/21/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Human apurinic/apyrimidinic endonuclease APE1 is one of participants of the DNA base excision repair pathway. APE1 processes AP-sites and many other types of DNA damage via hydrolysis of the phosphodiester bond on the 5' side of the lesion. APE1 also acts as an endoribonuclease, i.e., can cleave undamaged RNA. METHODS Using pre-steady-state kinetic analysis we examined the role of certain catalytically important amino acids in APE1 enzymatic pathway and described their involvement in the mechanism of the target nucleotide recognition. RESULTS Comparative analysis of the cleavage efficiency of damaged DNAs containing an abasic site, 5,6-dihydrouridine, or α-anomer of adenosine as well as 3'-5'-exonuclease degradation of undamaged DNA and endonuclease hydrolysis of RNA substrates by mutant APE1 enzymes containing a substitution of an active-site amino acid residue (D210N, N212A, T268D, M270A, or D308A) was performed. Detailed pre-steady-state kinetics of conformational changes of the enzyme and of DNA substrate molecules during recognition and cleavage of the abasic site were studied. CONCLUSIONS It was revealed that substitution T268D significantly disturbed initial DNA binding, whereas Asn212 is critical for the DNA-bending stage and catalysis. Substitution D210N increased the binding efficacy and blocked the catalytic reaction, but D308A decreased the binding efficacy owing to disruption of Mg2+ coordination. Finally, the substitution of Met270 also destabilized the enzyme-substrate complex but did not affect the catalytic reaction. SIGNIFICANCE It was found that the tested substitutions of the active-site amino acid residues affected different stages of the complex formation process as well as the catalytic reaction.
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30
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He Y, Yu Y, Wen X, Shi Y, Wu J, Guan Z, Cui M, Xiao C. A quencher-free 2-aminopurine modified hairpin aptasensor for ultrasensitive detection of Ochratoxin A. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 228:117780. [PMID: 31753651 DOI: 10.1016/j.saa.2019.117780] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 11/08/2019] [Accepted: 11/09/2019] [Indexed: 06/10/2023]
Abstract
A sensitive, efficient and quencher-free fluorescence aptasensor to detect Ochratoxin A (OTA) based on aptamer, 2-aminopurine (2AP) labeled Oligonucleotide sequence, as well as exonuclease I (Exo I) activity was developed. In which the aptamer specific to OTA was modified into a hairpin structure, and 8 bases at the 3' ends are exposed (H); also, 2AP is embedded in the oligonucleotide complementary to the 8 bases (2AP-probe).The detection principle based on 2AP-probe could be bonded to its complementary sequence and quenches the fluorescence of 2AP; The aptamer has a stronger affinity for the target than its complementary sequence; Exo I can dissociate single-stranded DNA and has little effect on double-stranded DNA as well as folded DNA. In the absence of OTA, the fluorescence of 2AP is quenched due to the complementary pairing of H and 2AP-probe; in the presence of OTA, H selective binding target is detached from 2AP-probe, and the fluorescence of 2AP is slightly restored. Moreover, when the Exo I is added to the detection system, 2AP-probe is dissociated by the Exo I to release the free 2AP, and the fluorescence of the system is further enhanced thereby realizing the detection of OTA. The detection limit of the aptasensor was low as 0.03 nM with a linear range of 0.5-100 nM. Moreover, the aptasensor has good selectivity and practicability and also has good potential in realizing the detection of toxic and harmful substances in food complex matrices.
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Affiliation(s)
- Yanhua He
- College of Food Science, Shanxi Normal University, Linfen 041004, PR China.
| | - Youwei Yu
- College of Food Science, Shanxi Normal University, Linfen 041004, PR China
| | - Xiaoye Wen
- Department of Chemistry, Shanxi Normal University, Linfen 041004, PR China
| | - Yan Shi
- College of Food Science, Shanxi Normal University, Linfen 041004, PR China
| | - Jianhu Wu
- College of Food Science, Shanxi Normal University, Linfen 041004, PR China
| | - Zhengping Guan
- College of Food Science, Shanxi Normal University, Linfen 041004, PR China
| | - Meilin Cui
- College of Food Science, Shanxi Normal University, Linfen 041004, PR China
| | - Chunling Xiao
- College of Food Science, Shanxi Normal University, Linfen 041004, PR China
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31
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Bielec K, Bubak G, Kalwarczyk T, Holyst R. Analysis of Brightness of a Single Fluorophore for Quantitative Characterization of Biochemical Reactions. J Phys Chem B 2020; 124:1941-1948. [PMID: 32059107 PMCID: PMC7497653 DOI: 10.1021/acs.jpcb.0c00770] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
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Intrinsic
molecular brightness (MB) is a number of emitted photons
per second per molecule. When a substrate labeled by a fluorophore
and a second unlabeled substrate form a complex in solution, the MB
of the fluorophore changes. Here we use this change to determine the equilibrium constant (K) for the formation of the complex at pM concentrations.
To illustrate this method, we used a reaction of DNA hybridization,
where only one of the strands was fluorescently labeled. We determined K at the substrate concentrations from 80 pM to 30 nM. We
validated this method against Förster resonance energy transfer
(FRET). This method is much simpler than FRET as it requires only
one fluorophore in the complex with a very small (a f̃ew percent)
change in MB.
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Affiliation(s)
- Krzysztof Bielec
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Grzegorz Bubak
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Tomasz Kalwarczyk
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Robert Holyst
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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32
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Nuthanakanti A, Ahmed I, Khatik SY, Saikrishnan K, Srivatsan SG. Probing G-quadruplex topologies and recognition concurrently in real time and 3D using a dual-app nucleoside probe. Nucleic Acids Res 2020; 47:6059-6072. [PMID: 31106340 PMCID: PMC6614846 DOI: 10.1093/nar/gkz419] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/30/2019] [Accepted: 05/06/2019] [Indexed: 12/30/2022] Open
Abstract
Comprehensive understanding of structure and recognition properties of regulatory nucleic acid elements in real time and atomic level is highly important to devise efficient therapeutic strategies. Here, we report the establishment of an innovative biophysical platform using a dual-app nucleoside analog, which serves as a common probe to detect and correlate different GQ structures and ligand binding under equilibrium conditions and in 3D by fluorescence and X-ray crystallography techniques. The probe (SedU) is composed of a microenvironment-sensitive fluorophore and an excellent anomalous X-ray scatterer (Se), which is assembled by attaching a selenophene ring at 5-position of 2'-deoxyuridine. SedU incorporated into the loop region of human telomeric DNA repeat fluorescently distinguished subtle differences in GQ topologies and enabled quantify ligand binding to different topologies. Importantly, anomalous X-ray dispersion signal from Se could be used to determine the structure of GQs. As the probe is minimally perturbing, a direct comparison of fluorescence data and crystal structures provided structural insights on how the probe senses different GQ conformations without affecting the native fold. Taken together, our dual-app probe represents a new class of tool that opens up new experimental strategies to concurrently investigate nucleic acid structure and recognition in real time and 3D.
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Affiliation(s)
- Ashok Nuthanakanti
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Dr. Homi Bhabha Road, Pune 411008, India
| | - Ishtiyaq Ahmed
- Department of Biology, Indian Institute of Science Education and Research (IISER), Pune, Dr. Homi Bhabha Road, Pune 411008, India
| | - Saddam Y Khatik
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Dr. Homi Bhabha Road, Pune 411008, India
| | - Kayarat Saikrishnan
- Department of Biology, Indian Institute of Science Education and Research (IISER), Pune, Dr. Homi Bhabha Road, Pune 411008, India
- Correspondence may also be addressed to Kayarat Saikrishnan.
| | - Seergazhi G Srivatsan
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune, Dr. Homi Bhabha Road, Pune 411008, India
- To whom correspondence should be addressed. Tel: +91 2025908086;
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33
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Paterson KA, Arlt J, Jones AC. Dynamic and static quenching of 2-aminopurine fluorescence by the natural DNA nucleotides in solution. Methods Appl Fluoresc 2020; 8:025002. [PMID: 32000159 DOI: 10.1088/2050-6120/ab71c3] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
2-aminopurine (2AP) is a responsive fluorescent base analogue that is used widely as a probe of the local molecular environment in DNA. The ability of 2AP to report changes in local conformation and base-stacking interactions arises from the efficient quenching of its fluorescence by the natural DNA bases. However, the mechanism of this inter-base quenching remains imperfectly understood. Two previous studies of the collisional quenching of 2AP by the natural bases, in different buffer solutions, showed that dynamic quenching efficiency depends on the identity of the natural base, but disagreed on the relative quenching efficiencies of the bases. We report a comprehensive investigation of inter-base quenching of 2AP by the natural nucleoside monophosphates (NMPs), replicating the buffer conditions used in the previous studies. Using time-resolved fluorescence measurements to distinguish between dynamic and static quenching, we find that the dynamic quenching rate constants of the different bases show a consistent trend across both buffers, and this is in line with a charge-transfer mechanism. Time-resolved measurements also provide insight into static quenching, revealing formation of 2AP-NMP ground-state complexes in which 2AP displays a very short fluorescence lifetime, comparable to that seen in oligonucleotides. In these complexes, the dependence of the rate of quenching on the partner base also supports a charge-transfer mechanism.
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Affiliation(s)
- Kyle A Paterson
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom
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34
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Martinez-Fernandez L, Gustavsson T, Diederichsen U, Improta R. Excited State Dynamics of 8-Vinyldeoxyguanosine In Aqueous Solution Studied by Time-Resolved Fluorescence Spectroscopy and Quantum Mechanical Calculations. Molecules 2020; 25:E824. [PMID: 32070032 PMCID: PMC7071107 DOI: 10.3390/molecules25040824] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 02/10/2020] [Accepted: 02/10/2020] [Indexed: 02/08/2023] Open
Abstract
The fluorescent base guanine analog, 8-vinyl-deoxyguanosine (8vdG), is studied in solution using a combination of optical spectroscopies, notably femtosecond fluorescence upconversion and quantum chemical calculations, based on time-dependent density functional theory (TD-DFT) and including solvent effect by using a mixed discrete-continuum model. In all investigated solvents, the fluorescence is very long lived (3-4 ns), emanating from a stable excited state minimum with pronounced intramolecular charge-transfer character. The main non-radiative decay channel features a sizeable energy barrier and it is affected by the polarity and the H-bonding properties of the solvent. Calculations provide a picture of dynamical solvation effects fully consistent with the experimental results and show that the photophysical properties of 8vdG are modulated by the orientation of the vinyl group with respect to the purine ring, which in turn depends on the solvent. These findings may have importance for the understanding of the fluorescence properties of 8vdG when incorporated in a DNA helix.
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Affiliation(s)
- Lara Martinez-Fernandez
- Departamento de Química, Facultad de Ciencias and IADCHEM (Institute for Advanced Research in Chemistry) Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain;
| | - Thomas Gustavsson
- Université Paris-Saclay, CEA, CNRS, LIDYL, 91191 Gif-sur-Yvette, France
| | - Ulf Diederichsen
- Univ Goettingen, Inst Organ & Biomol Chem, Tammannstr 2, D-37077 Goettingen, Germany;
| | - Roberto Improta
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, I-80134 Napoli, Italy
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35
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Kladova OA, Kuznetsova AA, Barthes NPF, Michel BY, Burger A, Fedorova OS, Kuznetsov NA. New Fluorescent Analogs of Nucleotides Based on 3-Hydroxychromone for Recording Conformational Changes of DNA. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2020. [DOI: 10.1134/s1068162019060220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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36
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Sarkar B, Ishii K, Tahara T. Microsecond Conformational Dynamics of Biopolymers Revealed by Dynamic-Quenching Two-Dimensional Fluorescence Lifetime Correlation Spectroscopy with Single Dye Labeling. J Phys Chem Lett 2019; 10:5536-5541. [PMID: 31393133 DOI: 10.1021/acs.jpclett.9b01513] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The single-molecule Förster resonance energy transfer (smFRET) technique is widely used for studying conformational dynamics of biopolymers. However, smFRET requires double dye labeling and is usually utilized for detecting dynamics on slow time scales (≳ milliseconds). In this Letter, we report dynamic-quenching two-dimensional fluorescence lifetime correlation spectroscopy (DQ 2D FLCS) that can elucidate the microsecond conformational dynamics of biopolymers with only single dye labeling. In DQ 2D FLCS, the difference in solvent accessibility of the labeled dye makes the fluorescence lifetime different, which is used for distinguishing different conformers. By applying DQ 2D FLCS to a singly labeled DNA hairpin, we successfully detect microsecond interconversion dynamics between the open and closed forms and evaluate the state-specific solvent accessibility of each form with Stern-Volmer analysis. Because DQ 2D FLCS is sensitive to the local structural change, it is complementary to FRET-based 2D FLCS and thus is a new, powerful tool for studying structural dynamics of biopolymers.
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Affiliation(s)
- Bidyut Sarkar
- Molecular Spectroscopy Laboratory , RIKEN , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan
| | - Kunihiko Ishii
- Molecular Spectroscopy Laboratory , RIKEN , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan
- Ultrafast Spectroscopy Research Team , RIKEN Center for Advanced Photonics (RAP) , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan
| | - Tahei Tahara
- Molecular Spectroscopy Laboratory , RIKEN , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan
- Ultrafast Spectroscopy Research Team , RIKEN Center for Advanced Photonics (RAP) , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan
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37
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Liu X, Dong L, Wang L, Xu H, Gao S, Zhong L, Zhang S, Jiang T. 2-Aminopurine modified DNA probe for rapid and sensitive detection of l-cysteine. Talanta 2019; 202:520-525. [DOI: 10.1016/j.talanta.2019.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 04/15/2019] [Accepted: 05/02/2019] [Indexed: 02/09/2023]
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38
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Manna S, Srivatsan SG. Synthesis and Enzymatic Incorporation of a Responsive Ribonucleoside Probe That Enables Quantitative Detection of Metallo-Base Pairs. Org Lett 2019; 21:4646-4650. [PMID: 31184159 PMCID: PMC6794643 DOI: 10.1021/acs.orglett.9b01544] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
![]()
Synthesis of a highly
responsive fluorescent ribonucleoside analogue
based on a 5-methoxybenzofuran uracil core, enzymatic incorporation
of its triphosphate substrate into RNA transcripts, and its utility
in the specific detection and estimation of Hg2+-ion-mediated
metallo-base pair formation in DNA–RNA and RNA–RNA duplexes
are described.
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Affiliation(s)
- Sudeshna Manna
- Department of Chemistry , Indian Institute of Science Education and Research (IISER) Pune , Dr. Homi Bhabha Road , Pune 411008 , India
| | - Seergazhi G Srivatsan
- Department of Chemistry , Indian Institute of Science Education and Research (IISER) Pune , Dr. Homi Bhabha Road , Pune 411008 , India
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39
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Tyugashev TE, Vorobjev YN, Kuznetsova AA, Lukina MV, Kuznetsov NA, Fedorova OS. Roles of Active-Site Amino Acid Residues in Specific Recognition of DNA Lesions by Human 8-Oxoguanine-DNA Glycosylase (OGG1). J Phys Chem B 2019; 123:4878-4887. [PMID: 31117610 DOI: 10.1021/acs.jpcb.9b02949] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Human 8-oxoguanine-DNA glycosylase (hOGG1) possesses very high specificity for 8-oxoguanine (oxoG), even though this damaged base differs from normal guanine by only two atoms. Our aim was to determine the roles of certain catalytically important amino acid residues in the hOGG1 enzymatic pathway and describe their involvement in the mechanism of DNA lesion recognition. Molecular dynamic simulation and pre-steady-state fluorescence kinetics were performed to analyze the conformational behavior of wild-type hOGG1 and mutants G42S, D268A, and K249Q, as well as damaged and undamaged DNA. A loss of electrostatic interactions in the K249Q mutant leads to the disruption of specific contacts in the active site of the enzyme and the loss of catalytic activity. The absence of residue Asp-268 abrogates the ability of the enzyme to fully flip out the oxoG base from the double helix, thereby disrupting proper positioning of the damaged base in the active site. Furthermore, substitution of Gly-42 with Ser, which forms a damage-specific H-bond with the N7 atom of the oxoG base, creates a stable H-bond between N7 of undamaged G and Oγ of Ser-42. Nevertheless, positioning of the undamaged base in the active site is unsuitable for catalytic hydrolysis of the N-glycosidic bond.
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Affiliation(s)
- Timofey E Tyugashev
- Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Avenue 8 , Novosibirsk 630090 , Russia
| | - Yury N Vorobjev
- Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Avenue 8 , Novosibirsk 630090 , Russia
| | - Alexandra A Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Avenue 8 , Novosibirsk 630090 , Russia
| | - Maria V Lukina
- Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Avenue 8 , Novosibirsk 630090 , Russia
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Avenue 8 , Novosibirsk 630090 , Russia.,Department of Natural Sciences , Novosibirsk State University , Pirogova Street 2 , Novosibirsk 630090 , Russia
| | - Olga S Fedorova
- Institute of Chemical Biology and Fundamental Medicine , Lavrentyev Avenue 8 , Novosibirsk 630090 , Russia.,Department of Natural Sciences , Novosibirsk State University , Pirogova Street 2 , Novosibirsk 630090 , Russia
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40
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Alekseeva IV, Davletgildeeva AT, Arkova OV, Kuznetsov NA, Fedorova OS. The impact of single-nucleotide polymorphisms of human apurinic/apyrimidinic endonuclease 1 on specific DNA binding and catalysis. Biochimie 2019; 163:73-83. [PMID: 31150756 DOI: 10.1016/j.biochi.2019.05.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 05/23/2019] [Indexed: 10/26/2022]
Abstract
Human apurinic/apyrimidinic (AP) endonuclease APE1 is a crucial enzyme of the base excision repair (BER) pathway, which is in charge of recognition and initiation of removal of AP-sites in DNA. It is known that some single-nucleotide polymorphism (SNP) variants of APE1 have a reduced activity as compared to wild-type APE1. It has been hypothesized that genetic variation in APE1 might be responsible for an increased risk of some types of cancer. In the present work, analysis of SNPs of the APE1 gene was performed to select the set of variants having substitutions of amino acid residues on the surface of the enzyme globule and in the DNA-binding site, thereby affecting protein-protein interactions or the catalytic reaction, respectively. For seven APE1 variants (R221C, N222H, R237A, G241R, M270T, R274Q, and P311S), conformational dynamics and catalytic activities were examined. The conformational changes in the molecules of APE1 variants and in a DNA substrate were recorded as fluorescence changes of Trp and 2-aminopurine residues, respectively, using the stopped-flow technique. The results made it possible to determine the kinetic mechanism underlying the interactions of the APE1 variants with DNA substrates, to calculate the rate constants of the elementary stages, and to identify the stages of the process affected by mutation.
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Affiliation(s)
- Irina V Alekseeva
- Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentyev Ave., Novosibirsk, 630090, Russia
| | - Anastasiia T Davletgildeeva
- Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentyev Ave., Novosibirsk, 630090, Russia; Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia
| | - Olga V Arkova
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 10 Lavrentyev Ave., Novosibirsk, 630090, Russia
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentyev Ave., Novosibirsk, 630090, Russia; Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia.
| | - Olga S Fedorova
- Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentyev Ave., Novosibirsk, 630090, Russia; Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., Novosibirsk, 630090, Russia.
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41
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McGovern-Gooch KR, Baird NJ. Fluorescence-based investigations of RNA-small molecule interactions. Methods 2019; 167:54-65. [PMID: 31129289 DOI: 10.1016/j.ymeth.2019.05.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/08/2019] [Accepted: 05/20/2019] [Indexed: 12/17/2022] Open
Abstract
Interrogating non-coding RNA structures and functions with small molecules is an area of rapidly increasing interest among biochemists and chemical biologists. However, many biochemical approaches to monitoring RNA structures are time-consuming and low-throughput, and thereby are only of limited utility for RNA-small molecule studies. Fluorescence-based techniques are powerful tools for rapid investigation of RNA conformations, dynamics, and interactions with small molecules. Many fluorescence methods are amenable to high-throughput analysis, enabling library screening for small molecule binders. In this review, we summarize numerous fluorescence-based approaches for identifying and characterizing RNA-small molecule interactions. We describe in detail a high-information content dual-reporter FRET assay we developed to characterize small molecule-induced conformational and stability changes. Our assay is uniquely suited as a platform for both small molecule discovery and thorough characterization of RNA-small molecule binding mechanisms. Given the growing recognition of non-coding RNAs as attractive targets for therapeutic intervention, we anticipate our FRET assay and other fluorescence-based techniques will be indispensable for the development of potent and specific small molecule inhibitors targeting RNA.
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Affiliation(s)
- Kayleigh R McGovern-Gooch
- Department of Chemistry & Biochemistry, University of the Sciences, Philadelphia, PA 19104 United States
| | - Nathan J Baird
- Department of Chemistry & Biochemistry, University of the Sciences, Philadelphia, PA 19104 United States.
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42
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A quencher-free DNAzyme beacon for fluorescently sensing uranyl ions via embedding 2-aminopurine. Biosens Bioelectron 2019; 135:166-172. [PMID: 31009884 DOI: 10.1016/j.bios.2019.04.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 03/24/2019] [Accepted: 04/10/2019] [Indexed: 01/23/2023]
Abstract
DNAzyme-based fluorescent probes have provided valuable protocols for detecting uranium, one of the most common radioactive contaminants in the environment, with ultra-high selectivity and sensitivity. Designing novel DNAzyme beacons to update the mode of fluorescence reporting and/or quenching will continuously enhance "turn-on" sensing performance as well as promote actual application of the biological probes. In this work, we developed a novel quencher-free DNAzyme beacon by embedding fluorescent 2-aminopurine for rapid detection of uranyl ion. 2-aminopurine is able to substitute adenine and keep strong fluorescence in single-stranded DNA whereas being quenched in the hybridized double-stranded DNA by the base-stacking interaction. The combination of such trait of 2-aminopurine and cleavage reaction of DNAzyme in the presence of target co-factors possesses two main advantages for ion sensing: simplicity for avoidance of extra quencher groups and high performance because of superiority of DNAzyme essence. The experimental conditions including embedding site, pH and salt concentration of buffer solutions, and the amount ratio of enzyme strand to substrate strand used to form DNAzymes were systematically optimized to inspire the highest performance of the biological beacon. Thus, a detection limit of 9.6 nM, a wide linear range from 5 nM to 400 nM (R2 = 0.997), and selectivity of more than 400 000-fold over other metal ions were achieved by the novel DNAzyme probes. The highly sensitive, selective and quencher-free DNAzyme probes accommodated a simple and cost-efficient alternative to current fluorescent counterparts, holding a great potential for further application in practical ion assay.
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43
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Böhnke H, Röttger K, Ingle RA, Marroux HJB, Bohnsack M, Schwalb NK, Orr-Ewing AJ, Temps F. Electronic Relaxation Dynamics of UV-Photoexcited 2-Aminopurine-Thymine Base Pairs in Watson-Crick and Hoogsteen Conformations. J Phys Chem B 2019; 123:2904-2914. [PMID: 30875228 DOI: 10.1021/acs.jpcb.9b02361] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The fluorescent analogue 2-aminopurine (2AP) of the canonical nucleobase adenine (6-aminopurine) base-pairs with thymine (T) without disrupting the helical structure of DNA. It therefore finds frequent use in molecular biology for probing DNA and RNA structures and conformational dynamics. However, detailed understanding of the processes responsible for fluorescence quenching remains largely elusive on a fundamental level. Although attempts have been made to ascribe decreased excited-state lifetimes to intrastrand charge-transfer and stacking interactions, possible influences from dynamic interstrand H-bonding have been widely ignored. Here, we investigate the electronic relaxation of UV-excited 2AP·T in Watson-Crick (WC) and Hoogsteen (HS) conformations. Although the WC conformation features slowed-down, monomer-like electronic relaxation in τ ∼ 1.6 ns toward ground-state recovery and triplet formation, the dynamics associated with 2AP·T in the HS motif exhibit faster deactivation in τ ∼ 70 ps. As recent research has revealed abundant transient interstrand H-bonding in the Hoogsteen motif for duplex DNA, the established model for dynamic fluorescence quenching may need to be revised in the light of our results. The underlying supramolecular photophysical mechanisms are discussed in terms of a proposed excited-state double-proton transfer as an efficient deactivation channel for recovery of the HS species in the electronic ground state.
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Affiliation(s)
- Hendrik Böhnke
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany
| | - Katharina Röttger
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany.,School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K
| | - Rebecca A Ingle
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K
| | - Hugo J B Marroux
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K
| | - Mats Bohnsack
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany
| | - Nina K Schwalb
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany
| | - Andrew J Orr-Ewing
- School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K
| | - Friedrich Temps
- Institute of Physical Chemistry , Christian-Albrechts-University Kiel , Olshausenstr. 40 , 24098 Kiel , Germany
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Krishna MS, Toh DFK, Meng Z, Ong AAL, Wang Z, Lu Y, Xia K, Prabakaran M, Chen G. Sequence- And Structure-Specific Probing of RNAs by Short Nucleobase-Modified dsRNA-Binding PNAs Incorporating a Fluorescent Light-up Uracil Analog. Anal Chem 2019; 91:5331-5338. [PMID: 30873827 DOI: 10.1021/acs.analchem.9b00280] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
RNAs are emerging as important biomarkers and therapeutic targets. The strategy of directly targeting double-stranded RNA (dsRNA) by triplex-formation is relatively underexplored mainly due to the weak binding at physiological conditions for the traditional triplex-forming oligonucleotides (TFOs). Compared to DNA and RNA, peptide nucleic acids (PNAs) are chemically stable and have a neutral peptide-like backbone, and thus, they show significantly enhanced binding to natural nucleic acids. We have successfully developed nucleobase-modified dsRNA-binding PNAs (dbPNAs) to facilitate structure-specific and selective recognition of dsRNA over single-stranded RNA (ssRNA) and dsDNA regions at near-physiological conditions. The triplex formation strategy facilitates the targeting of not only the sequence but also the secondary structure of RNA. Here, we report the development of novel dbPNA-based fluorescent light-up probes through the incorporation of A-U pair-recognizing 5-benzothiophene uracil (btU). The incorporation of btU into dbPNAs does not affect the binding affinity toward dsRNAs significantly, in most cases, as evidenced by our nondenaturing gel shift assay data. The blue fluorescence emission intensity of btU-modified dbPNAs is sequence- and structure-specifically enhanced by dsRNAs, including the influenza viral RNA panhandle duplex and HIV-1-1 ribosomal frameshift-inducing RNA hairpin, but not ssRNAs or DNAs, at 200 mM NaCl, pH 7.5. Thus, dbPNAs incorporating btU-modified and other further modified fluorescent nucleobases will be useful biochemical tools for probing and detecting RNA structures, interactions, and functions.
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Affiliation(s)
- Manchugondanahalli S Krishna
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Desiree-Faye Kaixin Toh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Zhenyu Meng
- Division of Mathematical Sciences, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Alan Ann Lerk Ong
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Zhenzhang Wang
- Temasek Life Science Laboratory , 1 Research Link, National University of Singapore , 117604 , Singapore
| | - Yunpeng Lu
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Kelin Xia
- Division of Mathematical Sciences, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
| | - Mookkan Prabakaran
- Temasek Life Science Laboratory , 1 Research Link, National University of Singapore , 117604 , Singapore
| | - Gang Chen
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , 21 Nanyang Link , 637371 , Singapore
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45
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Remington JM, McCullagh M, Kohler B. Molecular Dynamics Simulations of 2-Aminopurine-Labeled Dinucleoside Monophosphates Reveal Multiscale Stacking Kinetics. J Phys Chem B 2019; 123:2291-2304. [PMID: 30767498 DOI: 10.1021/acs.jpcb.8b12172] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular dynamics (MD) simulations of 2-aminopurine (2Ap)-labeled DNA dinucleoside monophosphates (DNMPs) were performed to investigate the hypothesis that base stacking dynamics occur on timescales sufficiently rapid to influence the emission signals measured in time-resolved fluorescence experiments. Analysis of multiple microsecond-length trajectories shows that the DNMPs sample all four coplanar stacking motifs. In addition, three metastable unstacked conformations are detected. A hidden Markov-state model (HMSM) was applied to the simulations to estimate transition rates between the stacked and unstacked states. Transitions between different stacked states generally occur at higher rates when the number of nucleobase faces requiring desolvation is minimized. Time constants for structural relaxation range between 1.6 and 25 ns, suggesting that emission from photoexcited 2Ap, which has an excited-state lifetime of 10 ns, is sensitive to base stacking kinetics. A master equation model for the excited-state population of 2Ap predicts multiexponential emission decays that reproduce the sub-10 ns emission decay lifetimes and amplitudes seen in experiments. Combining MD simulations with HMSM analysis is a powerful way to understand the dynamics that influence 2Ap excited-state relaxation and represents an important step toward using observed emission signals to validate MD simulations.
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Affiliation(s)
- Jacob M Remington
- Department of Chemistry and Biochemistry , Montana State University , Bozeman , Montana 59717 , United States
| | - Martin McCullagh
- Department of Chemistry , Colorado State University , Fort Collins , Colorado 80523 , United States
| | - Bern Kohler
- Department of Chemistry and Biochemistry , The Ohio State University , 100 West 18th Avenue , Columbus , Ohio 43210 , United States
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Brovarets’ OO, Hovorun DM. Key microstructural mechanisms of the 2-aminopurine mutagenicity: Results of extensive quantum-chemical research. J Biomol Struct Dyn 2019; 37:2716-2732. [DOI: 10.1080/07391102.2018.1495577] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Ol’ha O. Brovarets’
- Department of Molecular and Quantum Biophysics, Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, Kyiv, Ukraine
- Department of Molecular Biotechnology and Bioinformatics, Institute of High Technologies, Taras Shevchenko National University of Kyiv, 2-h Akademika Hlushkova Ave, Kyiv, Ukraine
| | - Dmytro M. Hovorun
- Department of Molecular and Quantum Biophysics, Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, Kyiv, Ukraine
- Department of Molecular Biotechnology and Bioinformatics, Institute of High Technologies, Taras Shevchenko National University of Kyiv, 2-h Akademika Hlushkova Ave, Kyiv, Ukraine
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Hwang SH, Kwon WY, Eun H, Jeong S, Park JS, Kim KJ, Kim HJ, Lee SH, Park K, Yoon JJ, Yang YH, Park KS. The use of a 2-aminopurine-containing split G-quadruplex for sequence-specific DNA detection. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2018; 46:S950-S955. [PMID: 30314413 DOI: 10.1080/21691401.2018.1521817] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A simple, sequence-specific DNA detection method, utilizing a fluorescent 2-aminopurine (2-AP) nucleobase analogue-containing split G-quadruplex as the key detection component, is described. In the sensor, the 2-AP-containing G-quadruplex is split into two segments and linked to a target-specific overhang sequence. The separate G-quadruplex sequences form an active G-quadruplex structure only in the presence of a complementary target DNA, which leads to a significant increase in the intensity of fluorescence from the 2-AP fluorophore. This simple, one-step, homogenous assay was successfully employed to detect target DNA with a high selectivity. In addition, the practical applicability of the detection method was demonstrated by its use in analyzing target DNAs in human serum. To the best of our knowledge, this is the first time that an investigation was carried out in which a fluorescent nucleobase analogue was incorporated into a split G-quadruplex structure and this structure was utilized as the foundation for a specific DNA sensor.
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Affiliation(s)
- Sung Hyun Hwang
- a Department of Biological Engineering, College of Engineering , Konkuk University , Seoul , Republic of Korea
| | - Woo Young Kwon
- a Department of Biological Engineering, College of Engineering , Konkuk University , Seoul , Republic of Korea
| | - Hyunmin Eun
- a Department of Biological Engineering, College of Engineering , Konkuk University , Seoul , Republic of Korea
| | - Sehan Jeong
- a Department of Biological Engineering, College of Engineering , Konkuk University , Seoul , Republic of Korea
| | - Jun Seok Park
- b Colorectal Cancer Center , Kyungpook National University Chilgok Hospital, School of Medicine, Kyungpook National University , Daegu , Republic of Korea
| | - Kwang Jin Kim
- c Urban Agriculture Research Division , National Institute of Horticultural and Herbal Science, Rural Development Administration , Wanju , Republic of Korea
| | - Hyung Joo Kim
- a Department of Biological Engineering, College of Engineering , Konkuk University , Seoul , Republic of Korea
| | - Sang Hyun Lee
- a Department of Biological Engineering, College of Engineering , Konkuk University , Seoul , Republic of Korea
| | - Kyungmoon Park
- d Department of Biological and Chemical Engineering , Hongik University , Sejong City , Republic of Korea
| | - Jeong-Jun Yoon
- e Intelligent Sustainable Materials R&D Group , Korea Institute of Industrial Technology (KITECH) , Cheonan-si , Republic of Korea
| | - Yung-Hun Yang
- a Department of Biological Engineering, College of Engineering , Konkuk University , Seoul , Republic of Korea
| | - Ki Soo Park
- a Department of Biological Engineering, College of Engineering , Konkuk University , Seoul , Republic of Korea
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48
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Du Y, Peng P, Li T. Logic circuit controlled multi-responsive branched DNA scaffolds. Chem Commun (Camb) 2018; 54:6132-6135. [PMID: 29808870 DOI: 10.1039/c8cc03387k] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A logic circuit controlled multi-responsive sensing platform built on a three-way DNA junction (TWJ) is reported. It enabled the construction of novel fluorescent sensing platforms responsive to any target out of HIV gene, ATP and pH value, and furthermore were logically regulated by two other targets and then behaved as different logic circuits, which consist of two tandem AND gates or cascaded NAND and INH gates by varying the positions of the fluorescent tags.
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Affiliation(s)
- Yi Du
- Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China.
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Kuznetsova AA, Fedorova OS, Kuznetsov NA. Kinetic Features of 3'-5' Exonuclease Activity of Human AP-Endonuclease APE1. Molecules 2018; 23:molecules23092101. [PMID: 30134601 PMCID: PMC6225374 DOI: 10.3390/molecules23092101] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 08/02/2018] [Accepted: 08/16/2018] [Indexed: 11/16/2022] Open
Abstract
Human apurinic/apyrimidinic (AP)-endonuclease APE1 is one of the key enzymes taking part in the repair of damage to DNA. The primary role of APE1 is the initiation of the repair of AP-sites by catalyzing the hydrolytic incision of the phosphodiester bond immediately 5' to the damage. In addition to the AP-endonuclease activity, APE1 possesses 3'-5' exonuclease activity, which presumably is responsible for cleaning up nonconventional 3' ends that were generated as a result of DNA damage or as transition intermediates in DNA repair pathways. In this study, the kinetic mechanism of 3'-end nucleotide removal in the 3'-5' exonuclease process catalyzed by APE1 was investigated under pre-steady-state conditions. DNA substrates were duplexes of deoxyribonucleotides with one 5' dangling end and it contained a fluorescent 2-aminopurine residue at the 1st, 2nd, 4th, or 6th position from the 3' end of the short oligonucleotide. The impact of the 3'-end nucleotide, which contained mismatched, undamaged bases or modified bases as well as an abasic site or phosphate group, on the efficiency of 3'-5' exonuclease activity was determined. Kinetic data revealed that the rate-limiting step of 3' nucleotide removal by APE1 in the 3'-5' exonuclease process is the release of the detached nucleotide from the enzyme's active site.
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Affiliation(s)
- Alexandra A Kuznetsova
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia.
| | - Olga S Fedorova
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia.
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia.
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., Novosibirsk 630090, Russia.
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50
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Fluorescent Trimethylated Naphthyridine Derivative with an Aminoalkyl Side Chain as the Tightest Non-aminoglycoside Ligand for the Bacterial A-site RNA. Chemistry 2018; 24:13862-13870. [DOI: 10.1002/chem.201802320] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 06/29/2018] [Indexed: 12/31/2022]
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