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Wiswedel R, Bui ATN, Kim J, Lee MK. Beta-Barrel Nanopores as Diagnostic Sensors: An Engineering Perspective. BIOSENSORS 2024; 14:345. [PMID: 39056622 PMCID: PMC11274599 DOI: 10.3390/bios14070345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 07/13/2024] [Accepted: 07/14/2024] [Indexed: 07/28/2024]
Abstract
Biological nanopores are ultrasensitive and highly attractive platforms for disease diagnostics, including the sequencing of viral and microbial genes and the detection of biomarkers and pathogens. To utilize biological nanopores as diagnostic sensors, they have been engineered through various methods resulting in the accurate and highly sensitive detection of biomarkers and disease-related biomolecules. Among diverse biological nanopores, the β-barrel-containing nanopores have advantages in nanopore engineering because of their robust structure, making them well-suited for modifications. In this review, we highlight the engineering approaches for β-barrel-containing nanopores used in single-molecule sensing for applications in early diagnosis and prognosis. In the highlighted studies, β-barrel nanopores can be modified by genetic mutation to change the structure; alter charge distributions; or add enzymes, aptamers, and protein probes to enhance sensitivity and accuracy. Furthermore, this review discusses challenges and future perspectives for advancing nanopore-based diagnostic sensors.
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Affiliation(s)
- Rani Wiswedel
- Critical Diseases Diagnostics Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea; (R.W.); (A.T.N.B.); (J.K.)
- Department of Proteome Structural Biology, KRIBB School of Bioscience, University of Science and Technology, Daejeon 34113, Republic of Korea
| | - Anh Thi Ngoc Bui
- Critical Diseases Diagnostics Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea; (R.W.); (A.T.N.B.); (J.K.)
| | - Jinhyung Kim
- Critical Diseases Diagnostics Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea; (R.W.); (A.T.N.B.); (J.K.)
- Department of Proteome Structural Biology, KRIBB School of Bioscience, University of Science and Technology, Daejeon 34113, Republic of Korea
| | - Mi-Kyung Lee
- Critical Diseases Diagnostics Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea; (R.W.); (A.T.N.B.); (J.K.)
- Department of Proteome Structural Biology, KRIBB School of Bioscience, University of Science and Technology, Daejeon 34113, Republic of Korea
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2
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Ivanov YD, Ableev AN, Shumov ID, Ivanova IA, Vaulin NV, Lebedev DV, Bukatin AS, Mukhin IS, Archakov AI. Registration of Functioning of a Single Horseradish Peroxidase Macromolecule with a Solid-State Nanopore. Int J Mol Sci 2023; 24:15636. [PMID: 37958620 PMCID: PMC10647385 DOI: 10.3390/ijms242115636] [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: 08/15/2023] [Revised: 09/22/2023] [Accepted: 09/26/2023] [Indexed: 11/15/2023] Open
Abstract
Currently, nanopore-based technology for the determination of the functional activity of single enzyme molecules continues its development. The use of natural nanopores for studying single enzyme molecules is known. At that, the approach utilizing artificial solid-state nanopores is also promising but still understudied. Herein, we demonstrate the use of a nanotechnology-based approach for the investigation of the enzymatic activity of a single molecule of horseradish peroxidase with a solid-state nanopore. The artificial 5 nm solid-state nanopore has been formed in a 40 nm thick silicon nitride structure. A single molecule of HRP has been entrapped into the nanopore. The activity of the horseradish peroxidase (HRP) enzyme molecule inserted in the nanopore has been monitored by recording the time dependence of the ion current through the nanopore in the course of the reaction of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) oxidation reaction. We have found that in the process of ABTS oxidation in the presence of 2.5 mM hydrogen peroxide, individual HRP enzyme molecules are able to retain activity for approximately 700 s before a decrease in the ion current through the nanopore, which can be explained by structural changes of the enzyme.
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Affiliation(s)
- Yuri D. Ivanov
- Institute of Biomedical Chemistry, 10, Pogodinskaya St., Moscow 119121, Russia; (A.N.A.); (I.D.S.); (I.A.I.); (A.I.A.)
| | - Alexander N. Ableev
- Institute of Biomedical Chemistry, 10, Pogodinskaya St., Moscow 119121, Russia; (A.N.A.); (I.D.S.); (I.A.I.); (A.I.A.)
| | - Ivan D. Shumov
- Institute of Biomedical Chemistry, 10, Pogodinskaya St., Moscow 119121, Russia; (A.N.A.); (I.D.S.); (I.A.I.); (A.I.A.)
| | - Irina A. Ivanova
- Institute of Biomedical Chemistry, 10, Pogodinskaya St., Moscow 119121, Russia; (A.N.A.); (I.D.S.); (I.A.I.); (A.I.A.)
| | - Nikita V. Vaulin
- Laboratory of Renewable Energy Sources, St. Petersburg Academic University, 8/3, Khlopina st., St. Petersburg 194021, Russia; (N.V.V.); (D.V.L.); (A.S.B.); (I.S.M.)
- Institute for Analytical Instrumentation RAS, 31-33 Lit. A, Ivana Chernykh St., St. Petersburg 198095, Russia
| | - Denis V. Lebedev
- Laboratory of Renewable Energy Sources, St. Petersburg Academic University, 8/3, Khlopina st., St. Petersburg 194021, Russia; (N.V.V.); (D.V.L.); (A.S.B.); (I.S.M.)
- Institute for Analytical Instrumentation RAS, 31-33 Lit. A, Ivana Chernykh St., St. Petersburg 198095, Russia
- Institute of Chemistry, Saint Petersburg State University, 7/9, Universitetskaya Nab., St. Petersburg 199034, Russia
| | - Anton S. Bukatin
- Laboratory of Renewable Energy Sources, St. Petersburg Academic University, 8/3, Khlopina st., St. Petersburg 194021, Russia; (N.V.V.); (D.V.L.); (A.S.B.); (I.S.M.)
- Institute for Analytical Instrumentation RAS, 31-33 Lit. A, Ivana Chernykh St., St. Petersburg 198095, Russia
| | - Ivan S. Mukhin
- Laboratory of Renewable Energy Sources, St. Petersburg Academic University, 8/3, Khlopina st., St. Petersburg 194021, Russia; (N.V.V.); (D.V.L.); (A.S.B.); (I.S.M.)
- Higher School of Engineering Physics, Peter the Great Polytechnic University, 26, Polytehnicheskaya St., St. Petersburg 194021, Russia
| | - Alexander I. Archakov
- Institute of Biomedical Chemistry, 10, Pogodinskaya St., Moscow 119121, Russia; (A.N.A.); (I.D.S.); (I.A.I.); (A.I.A.)
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3
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Kim M, Foster JC, Moore MD, Chen M. Improving Single-Molecule Antibody Detection Selectivity through Optimization of Peptide Epitope Presentation in OmpG Nanopore. ACS Sens 2023. [PMID: 37379512 DOI: 10.1021/acssensors.3c00528] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
Outer membrane protein G (OmpG) is a monomeric porin found in Escherichia coli, which possesses seven flexible loops. OmpG has been engineered as a nanopore sensor, where its loops can host affinity epitopes for selective detection of biological molecules. In this study, we investigated various loop positions to incorporate a FLAG peptide antigen epitope in the most flexible loop 6 and tested the efficacy and sensitivity of these nanopore constructs in antibody detection. We observed an OmpG construct containing inserted FLAG sequence, which exhibited strong interaction with anti-FLAG antibodies in flow cytometry; however, it could not translate molecule interactions into a readable signal in current recordings. Further optimization of the peptide presentation strategy by replacing specific sections of loop 6 sequences with the FLAG tag created a construct capable of generating unique and distinct signals when interacting with various monoclonal or polyclonal anti-FLAG clones IgG antibodies in the mixture. The peptide display scheme demonstrated in this study can be generalized for the engineering of OmpG sensors, which can be used for screening and validating positive clones during antibody development, as well as for real-time quality control of cell cultures in monoclonal antibody production.
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Affiliation(s)
- Minji Kim
- Department of Food Science, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Joshua C Foster
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Matthew D Moore
- Department of Food Science, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Min Chen
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
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4
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Foster JC, Pham B, Pham R, Kim M, Moore MD, Chen M. An Engineered OmpG Nanopore with Displayed Peptide Motifs for Single-Molecule Multiplex Protein Detection. Angew Chem Int Ed Engl 2023; 62:e202214566. [PMID: 36457283 PMCID: PMC9898208 DOI: 10.1002/anie.202214566] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 11/29/2022] [Accepted: 11/29/2022] [Indexed: 12/05/2022]
Abstract
Molecular detection via nanopore, achieved by monitoring changes in ionic current arising from analyte interaction with the sensor pore, is a promising technology for multiplex sensing development. Outer Membrane Protein G (OmpG), a monomeric porin possessing seven functionalizable loops, has been reported as an effective sensing platform for selective protein detection. Using flow cytometry to screen unfavorable constructs, we identified two OmpG nanopores with unique peptide motifs displayed in either loop 3 or 6, which also exhibited distinct analyte signals in single-channel current recordings. We exploited these motif-displaying loops concurrently to facilitate single-molecule multiplex protein detection in a mixture. We additionally report a strategy to increase sensor sensitivity via avidity motif display. These sensing schemes may be expanded to more sophisticated designs utilizing additional loops to increase multiplicity and sensitivity.
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Affiliation(s)
- Joshua C Foster
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Bach Pham
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA 01003, USA
- Current address: Department of Chemistry, University of Science, Vietnam National University, Hanoi, Vietnam
| | - Ryan Pham
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Minji Kim
- Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Matthew D Moore
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA 01003, USA
- Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Min Chen
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, MA 01003, USA
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA 01003, USA
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5
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Enzymology on an Electrode and in a Nanopore: Analysis Algorithms, Enzyme Kinetics, and Perspectives. BIONANOSCIENCE 2022. [DOI: 10.1007/s12668-022-01037-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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6
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Ghimire ML, Gibbs DR, Mahmoud R, Dhakal S, Reiner JE. Nanopore Analysis as a Tool for Studying Rapid Holliday Junction Dynamics and Analyte Binding. Anal Chem 2022; 94:10027-10034. [PMID: 35786863 DOI: 10.1021/acs.analchem.2c00342] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Holliday junctions (HJs) are an important class of nucleic acid structure utilized in DNA break repair processes. As such, these structures have great importance as therapeutic targets and for understanding the onset and development of various diseases. Single-molecule fluorescence resonance energy transfer (smFRET) has been used to study HJ structure-fluctuation kinetics, but given the rapid time scales associated with these kinetics (approximately sub-milliseconds) and the limited bandwidth of smFRET, these studies typically require one to slow down the structure fluctuations using divalent ions (e.g., Mg2+). This modification limits the ability to understand and model the underlying kinetics associated with HJ fluctuations. We address this here by utilizing nanopore sensing in a gating configuration to monitor DNA structure fluctuations without divalent ions. A nanopore analysis shows that HJ fluctuations occur on the order of 0.1-10 ms and that the HJ remains locked in a single conformation with short-lived transitions to a second conformation. It is not clear what role the nanopore plays in affecting these kinetics, but the time scales observed indicate that HJs are capable of undergoing rapid transitions that are not detectable with lower bandwidth measurement techniques. In addition to monitoring rapid HJ fluctuations, we also report on the use of nanopore sensing to develop a highly selective sensor capable of clear and rapid detection of short oligo DNA strands that bind to various HJ targets.
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Affiliation(s)
- Madhav L Ghimire
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Dalton R Gibbs
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Roaa Mahmoud
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Soma Dhakal
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Joseph E Reiner
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284, United States
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7
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Mapping the conformational energy landscape of Abl kinase using ClyA nanopore tweezers. Nat Commun 2022; 13:3541. [PMID: 35725977 PMCID: PMC9209526 DOI: 10.1038/s41467-022-31215-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 06/07/2022] [Indexed: 02/06/2023] Open
Abstract
Protein kinases play central roles in cellular regulation by catalyzing the phosphorylation of target proteins. Kinases have inherent structural flexibility allowing them to switch between active and inactive states. Quantitative characterization of kinase conformational dynamics is challenging. Here, we use nanopore tweezers to assess the conformational dynamics of Abl kinase domain, which is shown to interconvert between two major conformational states where one conformation comprises three sub-states. Analysis of kinase-substrate and kinase-inhibitor interactions uncovers the functional roles of relevant states and enables the elucidation of the mechanism underlying the catalytic deficiency of an inactive Abl mutant G321V. Furthermore, we obtain the energy landscape of Abl kinase by quantifying the population and transition rates of the conformational states. These results extend the view on the dynamic nature of Abl kinase and suggest nanopore tweezers can be used as an efficient tool for other members of the human kinome. Quantitative characterization of kinase conformational dynamics remains challenging. Here, the authors show that protein nanopore tweezers allow analyzing the conformational energy landscape and ligand binding of the Abl kinase domain.
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8
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Modifying the pH sensitivity of OmpG nanopore for improved detection at acidic pH. Biophys J 2022; 121:731-741. [PMID: 35131293 PMCID: PMC8943698 DOI: 10.1016/j.bpj.2022.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 01/02/2022] [Accepted: 01/25/2022] [Indexed: 11/22/2022] Open
Abstract
The outer membrane protein G (OmpG) nanopore is a monomeric β-barrel channel consisting of seven flexible extracellular loops. Its most flexible loop, loop 6, can be used to host high-affinity binding ligands for the capture of protein analytes, which induces characteristic current patterns for protein identification. At acidic pH, the ability of OmpG to detect protein analytes is hampered by its tendency toward the closed state, which renders the nanopore unable to reveal current signal changes induced by bound analytes. In this work, critical residues that control the pH-dependent gating of loop 6 were identified, and an OmpG nanopore that can stay predominantly open at a broad range of pHs was created by mutating these pH-sensitive residues. A short single-stranded DNA was chemically tethered to the pH-insensitive OmpG to demonstrate the utility of the OmpG nanopore for sensing complementary DNA and a DNA binding protein at an acidic pH.
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9
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Shorkey SA, Du J, Pham R, Strieter ER, Chen M. Real-Time and Label-Free Measurement of Deubiquitinase Activity with a MspA Nanopore. Chembiochem 2021; 22:2688-2692. [PMID: 34060221 PMCID: PMC8416795 DOI: 10.1002/cbic.202100092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 05/10/2021] [Indexed: 02/06/2023]
Abstract
Covalently attaching ubiquitin (Ub) to cellular proteins as a post-translational modification can result in altered function of modified proteins. Enzymes regulating Ub as a post-translational modification, such as ligases and deubiquitinases, are challenging to characterize in part due to the low throughput of in-vitro assays. Single-molecule nanopore based assays have the advantage of detecting proteins with high specificity and resolution, and in a label-free, real-time fashion. Here we demonstrate the use of a MspA nanopore for discriminating and quantifying Ub proteins. We further applied the MspA pore to measure the Ub-chain disassembly activity of UCH37, a proteasome associated deubiquitinase. The implementation of this MspA system into nanopore arrays could enable high throughput characterizations of unknown deubiquitinases as well as drug screening against disease related enzymes.
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Affiliation(s)
- Spencer A Shorkey
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Jiale Du
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Ryan Pham
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Eric R Strieter
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA 01003, USA
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Min Chen
- Molecular and Cellular Biology Graduate Program, University of Massachusetts Amherst, Amherst, MA 01003, USA
- Department of Chemistry, University of Massachusetts Amherst, Amherst, MA 01003, USA
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10
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Chen X, Zhang Y, Arora P, Guan X. Nanopore Stochastic Sensing Based on Non-covalent Interactions. Anal Chem 2021; 93:10974-10981. [PMID: 34319076 DOI: 10.1021/acs.analchem.1c02102] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A variety of species could be detected by using nanopores engineered with various recognition sites based upon non-covalent interactions, including electrostatic, aromatic, and hydrophobic interactions. The existence of these engineered non-covalent bonding sites was supported by the single-channel recording technique. The advantage of the non-covalent interaction-based sensing strategy was that the recognition site of the engineered nanopore was not specific for a particular molecule but instead selective for a class of species (e.g., cationic, anionic, aromatic, and hydrophobic). Since different species produce current modulations with quite different signatures represented by amplitude, residence time, and even characteristic voltage-dependence curve, the non-covalent interaction-based nanopore sensor could not only differentiate individual molecules in the same category but also enable differentiation between species with similar structures or molecular weights. Hence, our developed non-covalent interaction-based nanopore sensing strategy may find useful application in the detection of molecules of medical and/or environmental importance.
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Affiliation(s)
- Xiaohan Chen
- Department of Chemistry, Illinois Institute of Technology, 3101 S. Dearborn Street, Chicago, Illinois 60616, United States
| | - Youwen Zhang
- Department of Chemistry, Illinois Institute of Technology, 3101 S. Dearborn Street, Chicago, Illinois 60616, United States
| | - Pearl Arora
- Department of Chemistry, Illinois Institute of Technology, 3101 S. Dearborn Street, Chicago, Illinois 60616, United States
| | - Xiyun Guan
- Department of Chemistry, Illinois Institute of Technology, 3101 S. Dearborn Street, Chicago, Illinois 60616, United States
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11
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Fahie MA, Candido J, Andree G, Chen M. Tuning Protein Discrimination Through Altering the Sampling Interface Formed between the Analyte and the OmpG Nanopore. ACS Sens 2021; 6:1286-1294. [PMID: 33599487 DOI: 10.1021/acssensors.0c02580] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Nanopore sensors capable of distinguishing homologous protein analytes are highly desirable tools for proteomics research and disease diagnostics. Recently, an engineered outer membrane protein G (OmpG) nanopore with a high-affinity ligand attached to a gating loop 6 showed specificity for distinguishing homologous proteins in complex mixtures. Here, we report the development of OmpG nanopores with the other six loops used as the anchoring point to host an affinity ligand for protein sensing. We investigated how the analyte binding to the affinity ligand located at different loops affects the detection sensitivity, selectivity, and specificity. Our results reveal that analytes weakly attracted to the OmpG nanopore surface are only detectable when the ligand is tethered to loop 6. In contrast, protein analytes that form a strong interaction with the OmpG surface via electrostatic attractions are distinguishable by all seven OmpG nanopore constructs. In addition, the same analyte can generate distinct binding signals with different OmpG nanopore constructs. The ability to exploit all seven OmpG loops will aid the design of a new generation of OmpG sensors with increased sensitivity, selectivity, and specificity for biomarker sensing.
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Affiliation(s)
- Monifa A. Fahie
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Jonathan Candido
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Gisele Andree
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Min Chen
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
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12
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Abstract
Many enzymatic activity assays are based on either (1) identifying and quantifying the enzyme with methods such as western blot or enzyme-linked substrate assay (ELISA) or (2) quantifying the enzymatic reaction by monitoring the changing levels of either product or substrate. We have generated an outer membrane protein G (OmpG)-based nanopore approach to distinguish enzyme identity as well as analyze the enzyme's catalytic activity. Here, we engineered an OmpG nanopore with a peptide cut site inserted into one of its loops to detect proteolytic behavior. In addition, we generated an OmpG nanopore with a single-stranded DNA attached to a loop for analyzing nucleolytic cleavage. This OmpG nanopore approach may be highly useful in analyzing specific enzymes in complex biological samples, or in directly determining kinetics of enzyme-substrate complex association and dissociation.
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13
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Sheng Y, Zhang S, Liu L, Wu H. Measuring Enzymatic Activities with Nanopores. Chembiochem 2020; 21:2089-2097. [DOI: 10.1002/cbic.202000079] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 03/21/2020] [Indexed: 12/20/2022]
Affiliation(s)
- Yingying Sheng
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Shouwen Zhang
- Neurophysiology Department Beijing ChaoYang Emergency Medical Center Beijing 100122 China
| | - Lei Liu
- Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
| | - Hai‐Chen Wu
- Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
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