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Sánchez-Visedo A, Gallego-Martínez B, Royo LJ, Soldado A, Valledor M, Campo JC, Ferrero FJ, Costa-Fernández JM, Fernández-Argüelles MT. MNAzymes and gold nanoparticles as isothermal signal amplification strategy for visual detection of miRNA. Mikrochim Acta 2023; 190:292. [PMID: 37458796 PMCID: PMC10352400 DOI: 10.1007/s00604-023-05868-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 06/08/2023] [Indexed: 07/20/2023]
Abstract
MicroRNAs (miRNAs) represent a class of small noncoding RNAs that are considered a novel emerging class of disease biomarkers in a variety of afflictions. Sensitive detection of miRNA is typically achieved using hybridization-based methods coupled with genetic amplification techniques. Although their sensitivity has improved, amplification techniques often present erroneous results due to their complexity. In addition, the use of these techniques is usually linked to the application of protein enzymes, the activity of which is dependent on the temperature and pH of the medium. To address these drawbacks, an alternative genetic enzyme for the highly sensitive detection of miRNAs is proposed in this work. Multicomponent nucleic acid enzymes (MNAzymes), coupled with the use of DNA-functionalized gold nanoparticles (AuNPs), were used in this study to develop an isothermal signal amplification strategy for visual genetic detection. miR146a, a biomarker of bovine mastitis present in milk, was selected as a model analyte. The developed methodology is easily carried out in 80 min at 50 °C, generating a low visual limit of detection of 250 pM based on the observation of a color change. The methodology was successfully applied to the detection of miR146a in raw cow milk samples.
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Affiliation(s)
- Adrián Sánchez-Visedo
- Department of Physical and Analytical Chemistry, University of Oviedo, Avenida Julian Clavería 8, 33006, Oviedo, Asturias, Spain
| | - Borja Gallego-Martínez
- Health Research Institute of Asturias, ISPA, Avenida Hospital Universitario, s/n 33011, Oviedo, Asturias, Spain
| | - Luis José Royo
- Department of Functional Biology, Genetics, University of Oviedo, Avenida Julián Claveria, s/n 33006, Oviedo, Asturias, Spain
| | - Ana Soldado
- Department of Physical and Analytical Chemistry, University of Oviedo, Avenida Julian Clavería 8, 33006, Oviedo, Asturias, Spain
| | - Marta Valledor
- Department of Electrical, Electronic, Communications and Systems Engineering, University of Oviedo, Campus of Gijón, 33204, Gijón, Spain
| | - Juan Carlos Campo
- Department of Electrical, Electronic, Communications and Systems Engineering, University of Oviedo, Campus of Gijón, 33204, Gijón, Spain
| | - Francisco Javier Ferrero
- Department of Electrical, Electronic, Communications and Systems Engineering, University of Oviedo, Campus of Gijón, 33204, Gijón, Spain.
| | - José Manuel Costa-Fernández
- Department of Physical and Analytical Chemistry, University of Oviedo, Avenida Julian Clavería 8, 33006, Oviedo, Asturias, Spain
| | - María Teresa Fernández-Argüelles
- Department of Physical and Analytical Chemistry, University of Oviedo, Avenida Julian Clavería 8, 33006, Oviedo, Asturias, Spain.
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2
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Chang T, He S, Amini R, Li Y. Functional Nucleic Acids Under Unusual Conditions. Chembiochem 2021; 22:2368-2383. [PMID: 33930229 DOI: 10.1002/cbic.202100087] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/24/2021] [Indexed: 02/06/2023]
Abstract
Functional nucleic acids (FNAs), including naturally occurring ribozymes and riboswitches as well as artificially created DNAzymes and aptamers, have been popular molecular toolboxes for diverse applications. Given the high chemical stability of nucleic acids and their ability to fold into diverse sequence-dependent structures, FNAs are suggested to be highly functional under unusual reaction conditions. This review will examine the progress of research on FNAs under conditions of low pH, high temperature, freezing conditions, and the inclusion of organic solvents and denaturants that are known to disrupt nucleic acid structures. The FNA species to be discussed include ribozymes, riboswitches, G-quadruplex-based peroxidase mimicking DNAzymes, RNA-cleaving DNAzymes, and aptamers. Research within this space has not only revealed the hidden talents of FNAs but has also laid important groundwork for pursuing these intriguing functional macromolecules for unique applications.
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Affiliation(s)
- Tianjun Chang
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, Canada
- Department of Biology, Institute of Resources and Environment, Henan Polytechnic University, Jiaozuo, 454000, Henan, P. R. China
| | - Sisi He
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, Canada
- School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen, 518055, Guangdong, P. R. China
| | - Ryan Amini
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, Canada
| | - Yingfu Li
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, L8S 4K1, Canada
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3
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Saleh LY, Ora M, Lönnberg T. Cleavage of an RNA Model Compound by an Arylmercury Complex. Chembiochem 2021; 22:1761-1764. [PMID: 33448598 PMCID: PMC8247959 DOI: 10.1002/cbic.202000799] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 01/13/2021] [Indexed: 11/22/2022]
Abstract
A water-soluble arylmercury complex has been synthesized, and its ability to catalyze the cleavage of the phosphodiester linkage of the RNA model compound adenylyl-3',5'-(2',3'-O-methyleneadenosine) has been assessed over a pH range of 3-8.5 and a catalyst concentration range of 0-7 mM. In the presence of 1 mM catalyst, the observed pH-rate profile featured a new pH-independent region between pH 6 and 7, the catalyzed reaction being as much as eight times faster than the background reaction. At pH 7, the acceleration increased linearly from three- to 17-fold upon increasing the catalyst concentration from 1 to 7 mM. The linear dependence indicates a relatively low affinity of the catalyst for the substrate and, hence, the potential for considerable improvement on tethering to an appropriate targeting group, such as an oligonucleotide.
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Affiliation(s)
- Lange Yakubu Saleh
- Department of ChemistryUniversity of TurkuVatselankatu 220014TurkuFinland
| | - Mikko Ora
- Department of ChemistryUniversity of TurkuVatselankatu 220014TurkuFinland
| | - Tuomas Lönnberg
- Department of ChemistryUniversity of TurkuVatselankatu 220014TurkuFinland
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4
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Peeters B, Safdar S, Daems D, Goos P, Spasic D, Lammertyn J. Solid-Phase PCR-Amplified DNAzyme Activity for Real-Time FO-SPR Detection of the MCR-2 Gene. Anal Chem 2020; 92:10783-10791. [PMID: 32638586 DOI: 10.1021/acs.analchem.0c02241] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The polymerase chain reaction (PCR) has been the gold standard molecular analysis technique for decades and has seen quite some evolution in terms of reaction components, methodology, and readout mechanisms. Nucleic acid enzymes (NAzymes) have been used to further exploit the applications of PCR, but so far the work was limited to the colorimetric G-quadruplex or fluorescent substrate cleaving NAzymes. In this study, a solid-phase, fiber optic surface plasmon resonance (FO-SPR) technique is presented as an alternative readout for PCR utilizing NAzymes. First, the surface cleavage activity of DNAzyme-extended amplicons (DNAzyme-amps) is established, followed by optimization of the PCR conditions, which are required for compatibility with the FO-SPR system. Next, by integrating the complement of a 10-23 DNAzyme into the primer pair, PCR-amplified DNAzyme-amps were generated, tested, and validated on qPCR for the detection of the antimicrobial resistance gene MCR-2. Once validated, this primer concept was developed as a one-step assay, driven by PCR-amplified DNAzymes, for FO-SPR-based sensitive and specific detection. Using gold nanoparticle labeled RNA-DNA hybrid strands as substrate for the DNAzyme, PCR-amplified DNAzyme-amps generated in the presence of MCR-2 gene were monitored in real-time, which resulted in an experimental limit of detection of 4 × 105 copy numbers or 6.6 fM. In addition, the DNAzyme-based FO-PCR assay was able to discriminate between the MCR-1 and MCR-2 genes, to further prove the specificity of this assay. Henceforth, this DNAzyme-based fiber optic PCR assay provides a universally applicable, real-time system for the detection of virtually any target NA, in a specific and sensitive manner.
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Affiliation(s)
- Bernd Peeters
- Department of Biosystems, Biosensors Group, KU Leuven, Willem de Croylaan 42, Leuven B-3001, Belgium
| | - Saba Safdar
- Department of Biosystems, Biosensors Group, KU Leuven, Willem de Croylaan 42, Leuven B-3001, Belgium
| | - Devin Daems
- Department of Biosystems, Biosensors Group, KU Leuven, Willem de Croylaan 42, Leuven B-3001, Belgium
| | - Peter Goos
- Department of Biosystems, Biostatistics Group, KU Leuven, Kasteelpark Arenberg 30, Leuven B-3001, Belgium
| | - Dragana Spasic
- Department of Biosystems, Biosensors Group, KU Leuven, Willem de Croylaan 42, Leuven B-3001, Belgium
| | - Jeroen Lammertyn
- Department of Biosystems, Biosensors Group, KU Leuven, Willem de Croylaan 42, Leuven B-3001, Belgium
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5
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Rosenbach H, Victor J, Etzkorn M, Steger G, Riesner D, Span I. Molecular Features and Metal Ions That Influence 10-23 DNAzyme Activity. Molecules 2020; 25:E3100. [PMID: 32646019 PMCID: PMC7412337 DOI: 10.3390/molecules25133100] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/25/2020] [Accepted: 07/03/2020] [Indexed: 12/17/2022] Open
Abstract
Deoxyribozymes (DNAzymes) with RNA hydrolysis activity have a tremendous potential as gene suppression agents for therapeutic applications. The most extensively studied representative is the 10-23 DNAzyme consisting of a catalytic loop and two substrate binding arms that can be designed to bind and cleave the RNA sequence of interest. The RNA substrate is cleaved between central purine and pyrimidine nucleotides. The activity of this DNAzyme in vitro is considerably higher than in vivo, which was suggested to be related to its divalent cation dependency. Understanding the mechanism of DNAzyme catalysis is hindered by the absence of structural information. Numerous biological studies, however, provide comprehensive insights into the role of particular deoxynucleotides and functional groups in DNAzymes. Here we provide an overview of the thermodynamic properties, the impact of nucleobase modifications within the catalytic loop, and the role of different metal ions in catalysis. We point out features that will be helpful in developing novel strategies for structure determination and to understand the mechanism of the 10-23 DNAzyme. Consideration of these features will enable to develop improved strategies for structure determination and to understand the mechanism of the 10-23 DNAzyme. These insights provide the basis for improving activity in cells and pave the way for developing DNAzyme applications.
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Affiliation(s)
- Hannah Rosenbach
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
| | - Julian Victor
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
| | - Manuel Etzkorn
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, Wilhelm-Johnen-Straße, 52428 Jülich, Germany
| | - Gerhard Steger
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
| | - Detlev Riesner
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
| | - Ingrid Span
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
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6
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Le Vay K, Salibi E, Song EY, Mutschler H. Nucleic Acid Catalysis under Potential Prebiotic Conditions. Chem Asian J 2020; 15:214-230. [PMID: 31714665 PMCID: PMC7003795 DOI: 10.1002/asia.201901205] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/05/2019] [Indexed: 01/25/2023]
Abstract
Catalysis by nucleic acids is indispensable for extant cellular life, and it is widely accepted that nucleic acid enzymes were crucial for the emergence of primitive life 3.5-4 billion years ago. However, geochemical conditions on early Earth must have differed greatly from the constant internal milieus of today's cells. In order to explore plausible scenarios for early molecular evolution, it is therefore essential to understand how different physicochemical parameters, such as temperature, pH, and ionic composition, influence nucleic acid catalysis and to explore to what extent nucleic acid enzymes can adapt to non-physiological conditions. In this article, we give an overview of the research on catalysis of nucleic acids, in particular catalytic RNAs (ribozymes) and DNAs (deoxyribozymes), under extreme and/or unusual conditions that may relate to prebiotic environments.
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Affiliation(s)
- Kristian Le Vay
- Biomimetic SystemsMax Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
| | - Elia Salibi
- Biomimetic SystemsMax Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
| | - Emilie Y. Song
- Biomimetic SystemsMax Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
| | - Hannes Mutschler
- Biomimetic SystemsMax Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
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7
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Safdar S, Ven K, van Lent J, Pavie B, Rutten I, Dillen A, Munck S, Lammertyn J, Spasic D. DNA-only, microwell-based bioassay for multiplex nucleic acid detection with single base-pair resolution using MNAzymes. Biosens Bioelectron 2020; 152:112017. [PMID: 31941617 DOI: 10.1016/j.bios.2020.112017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 01/08/2020] [Indexed: 12/17/2022]
Abstract
In disease diagnostics, single- and multiplex nucleic acid (NA) detection, with the potential to discriminate mutated strands, is of paramount importance. Current techniques that rely on target amplification or protein-enzyme based signal amplification are highly relevant, yet still plagued by diverse drawbacks including erroneous target amplification, and the limited stability of protein enzymes. As a solution, we present a multicomponent nucleic acid enzymes (MNAzymes)-based system for singleplex and multiplex detection of NA targets in microwells down to femtomolar (fM) concentrations, without the need for any target amplification or protein enzymes, while operating at room temperature and with single base-pair resolution. After successful validation of the MNAzymes in solution, their performance was further verified on beads in bulk and in femtoliter-sized microwells. The latter is not only a highly simplified system compared to previous microwell-based bioassays but, with the detection limit of 180 fM, it is to-date the most sensitive NAzyme-mediated, bead-based approach, that does not rely on target amplification or any additional signal amplification strategies. Furthermore, we demonstrated, for the first time, multiplexed target detection in microwells, both from buffer and nasopharyngeal swab samples, and presented superior single base-pair resolution of this assay. Because of the design flexibility of MNAzymes and direct demonstration in swab samples, this system holds great promise for multiplexed detection in other clinically relevant matrices without the need for any additional NA or protein components. Moreover, these findings open up the potential for the development of next-generation, protein-free diagnostic tools, including digital assays with single-molecule resolution.
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Affiliation(s)
- Saba Safdar
- Department of Biosystems, Biosensors Group, KU Leuven, 3001, Leuven, Belgium
| | - Karen Ven
- Department of Biosystems, Biosensors Group, KU Leuven, 3001, Leuven, Belgium
| | - Julie van Lent
- Department of Biosystems, Biosensors Group, KU Leuven, 3001, Leuven, Belgium
| | - Benjamin Pavie
- VIB-KU Leuven Center for Brain & Disease Research, KU Leuven, 3000, Leuven, Belgium
| | - Iene Rutten
- Department of Biosystems, Biosensors Group, KU Leuven, 3001, Leuven, Belgium
| | - Annelies Dillen
- Department of Biosystems, Biosensors Group, KU Leuven, 3001, Leuven, Belgium
| | - Sebastian Munck
- VIB-KU Leuven Center for Brain & Disease Research, KU Leuven, 3000, Leuven, Belgium
| | - Jeroen Lammertyn
- Department of Biosystems, Biosensors Group, KU Leuven, 3001, Leuven, Belgium.
| | - Dragana Spasic
- Department of Biosystems, Biosensors Group, KU Leuven, 3001, Leuven, Belgium
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8
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Nucleic acid-cleaving catalytic DNA for sensing and therapeutics. Talanta 2020; 211:120709. [PMID: 32070594 DOI: 10.1016/j.talanta.2019.120709] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 12/28/2019] [Accepted: 12/31/2019] [Indexed: 12/21/2022]
Abstract
DNAzymes with nucleic acid-cleaving catalytic activity are increasing in versatility through concerted efforts to discover new sequences with unique functions, and they are generating excitement in the sensing community as cheap, stable, amplifiable detection elements. This review provides a comprehensive list and detailed descriptions of the DNAzymes identified to date, classified by their associated small molecule or ion needed for catalysis; of note, this classification clarifies conserved regions of various DNAzymes that are not obvious in the literature. Furthermore, we detail the breadth of functionality of these DNA sequences as well as the range of reaction conditions under which they are useful. In addition, the utility of the DNAzymes in a variety of sensing and therapeutic applications is presented, detailing both their advantages and disadvantages.
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9
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Zheng X, Yang J, Zhou C, Zhang C, Zhang Q, Wei X. Allosteric DNAzyme-based DNA logic circuit: operations and dynamic analysis. Nucleic Acids Res 2019; 47:1097-1109. [PMID: 30541100 PMCID: PMC6379719 DOI: 10.1093/nar/gky1245] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/29/2018] [Accepted: 12/03/2018] [Indexed: 12/29/2022] Open
Abstract
Recently, due to the dual roles of DNA and enzyme, DNAzyme has been widely used in the field of DNA circuit, which has a wide range of applications in bio-engineered system, information processing and biocomputing. In fact, the activity of DNAzymes was regulated by subunits assembly, pH control and metal ions triggers. However, those regulations required to change the sequences of whole DNAzyme, as separating parts and inserting extra DNA sequence. Inspired by the allosteric regulation of proteins in nature, a new allosteric strategy is proposed to regulate the activity of DNAzyme without DNA sequences changes. In this strategy, DNA strand displacement was used to regulate the DNAzyme structure, through which the activity of DNAzyme was well controlled. The strategy was applied to E6-type DNAzymes, and the operations of DNA logic circuit (YES, OR, AND, cascading and feedback) were established and simulated with the dynamic analyses. The allosteric regulation has potential to construct more complicated molecular systems, which can be applied to bio-sensing and detection.
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Affiliation(s)
- Xuedong Zheng
- College of Computer Science, Shenyang Aerospace University, Shenyang 110136, China
| | - Jing Yang
- School of Control and Computer Engineering, North China Electric Power University, Beijing 102206, China
| | - Changjun Zhou
- College of Mathematics and Computer sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Cheng Zhang
- School of Electronics Engineering and Computer Science, Peking University, Key laboratory of High Confidence Software Technologies, Ministry of Education, Beijing 100871, China
| | - Qiang Zhang
- Key Laboratory of Advanced Design and Intelligent Computing, Dalian University, Ministry of Education, Dalian 116622, China
- School of Computer Scicence and Technology, Dalian University of Technology, Dalian 116024, China
| | - Xiaopeng Wei
- Key Laboratory of Advanced Design and Intelligent Computing, Dalian University, Ministry of Education, Dalian 116622, China
- School of Computer Scicence and Technology, Dalian University of Technology, Dalian 116024, China
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10
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Re-engineering 10-23 core DNA- and MNAzymes for applications at standard room temperature. Anal Bioanal Chem 2018; 411:205-215. [PMID: 30341659 DOI: 10.1007/s00216-018-1429-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/02/2018] [Accepted: 10/10/2018] [Indexed: 12/15/2022]
Abstract
DNA- and MNAzymes are nucleic acid-based enzymes (NAzymes), which infiltrated the otherwise protein-rich field of enzymology three decades ago. The 10-23 core NAzymes are one of the most widely used and well-characterized NAzymes, but often require elevated working temperatures or additional complex modifications for implementation at standard room temperatures. Here, we present a generally applicable method, based on thermodynamic principles governing hybridization, to re-engineer the existing 10-23 core NAzymes for use at 23 °C. To establish this, we first assessed the activity of conventional NAzymes in the presence of cleavable and non-cleavable substrate at 23 °C as well as over a temperature gradient. These tests pointed towards a non-catalytic mechanism of signal generation at 23 °C, suggesting that conventional NAzymes are not suited for use at this temperature. Following this, several novel NAzyme-substrate complexes were re-engineered from the conventional ones and screened for their performance at 23 °C. The complex with substrate and substrate-binding arms of the NAzymes shortened by four nucleotides on each terminus demonstrated efficient catalytic activity at 23 °C. This has been further validated over a dilution of enzymes or enzyme components, revealing their superior performance at 23 °C compared to the conventional 10-23 core NAzymes at their standard operating temperature of 55 °C. Finally, the proposed approach was applied to successfully re-engineer three other new MNAzymes for activity at 23 °C. As such, these re-engineered NAzymes present a remarkable addition to the field by further widening the diverse repertoire of NAzyme applications.
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11
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Kasprowicz A, Stokowa-Sołtys K, Jeżowska-Bojczuk M, Wrzesiński J, Ciesiołka J. Characterization of Highly Efficient RNA-Cleaving DNAzymes that Function at Acidic pH with No Divalent Metal-Ion Cofactors. ChemistryOpen 2016; 6:46-56. [PMID: 28168150 PMCID: PMC5288747 DOI: 10.1002/open.201600141] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 11/29/2016] [Indexed: 12/02/2022] Open
Abstract
Here, we describe the characterization of new RNA‐cleaving DNAzymes that showed the highest catalytic efficiency at pH 4.0 to 4.5, and were completely inactive at pH values higher than 5.0. Importantly, these DNAzymes did not require any divalent metal ion cofactors for catalysis. This clearly suggests that protonated nucleic bases are involved in the folding of the DNAzymes into catalytically active structures and/or in the cleavage mechanism. The trans‐acting DNAzyme variants were also catalytically active. Mutational analysis revealed a conservative character of the DNAzyme catalytic core that underpins the high structural requirements of the cleavage mechanism. A significant advantage of the described DNAzymes is that they are inactive at pH values close to physiological pH and under a wide range of conditions in the presence of monovalent and divalent metal ions. These pH‐dependent DNAzymes could be used as molecular cassettes in biotechnology or nanotechnology, in molecular processes that consist of several steps. The results expand the repertoire of DNAzymes that are active under nonphysiological conditions and shed new light on the possible mechanisms of catalysis.
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Affiliation(s)
- Aleksandra Kasprowicz
- Institute of Bioorganic Chemistry Polish Academy of Sciences Noskowskiego 12/14 61-704 Poznań Poland
| | | | | | - Jan Wrzesiński
- Institute of Bioorganic Chemistry Polish Academy of Sciences Noskowskiego 12/14 61-704 Poznań Poland
| | - Jerzy Ciesiołka
- Institute of Bioorganic Chemistry Polish Academy of Sciences Noskowskiego 12/14 61-704 Poznań Poland
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