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Single-Molecule Chemical Reactions Unveiled in Molecular Junctions. Processes (Basel) 2022. [DOI: 10.3390/pr10122574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022] Open
Abstract
Understanding chemical processes at the single-molecule scale represents the ultimate limit of analytical chemistry. Single-molecule detection techniques allow one to reveal the detailed dynamics and kinetics of a chemical reaction with unprecedented accuracy. It has also enabled the discoveries of new reaction pathways or intermediates/transition states that are inaccessible in conventional ensemble experiments, which is critical to elucidating their intrinsic mechanisms. Thanks to the rapid development of single-molecule junction (SMJ) techniques, detecting chemical reactions via monitoring the electrical current through single molecules has received an increasing amount of attention and has witnessed tremendous advances in recent years. Research efforts in this direction have opened a new route for probing chemical and physical processes with single-molecule precision. This review presents detailed advancements in probing single-molecule chemical reactions using SMJ techniques. We specifically highlight recent progress in investigating electric-field-driven reactions, reaction dynamics and kinetics, host–guest interactions, and redox reactions of different molecular systems. Finally, we discuss the potential of single-molecule detection using SMJs across various future applications.
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Engelbrekt C, Nazmutdinov RR, Shermukhamedov S, Ulstrup J, Zinkicheva TT, Xiao X. Complex single‐molecule and molecular scale entities in electrochemical environments: Mechanisms and challenges. ELECTROCHEMICAL SCIENCE ADVANCES 2021. [DOI: 10.1002/elsa.202100157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Christian Engelbrekt
- Department of Chemistry Technical University of Denmark Building 207, DK0‐2800 Kgs. Lyngby Denmark
| | - Renat R. Nazmutdinov
- Department of Inorganic Chemistry Kazan National Research Technological University Karl Marx Str. 68 Kazan 420015 Russian Federation
| | - Shokirbek Shermukhamedov
- Department of Inorganic Chemistry Kazan National Research Technological University Karl Marx Str. 68 Kazan 420015 Russian Federation
| | - Jens Ulstrup
- Department of Chemistry Technical University of Denmark Building 207, DK0‐2800 Kgs. Lyngby Denmark
| | - Tamara T. Zinkicheva
- Department of Inorganic Chemistry Kazan National Research Technological University Karl Marx Str. 68 Kazan 420015 Russian Federation
| | - Xinxin Xiao
- Department of Chemistry Technical University of Denmark Building 207, DK0‐2800 Kgs. Lyngby Denmark
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3
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Gonzaga de França Lopes L, Gouveia Júnior FS, Karine Medeiros Holanda A, Maria Moreira de Carvalho I, Longhinotti E, Paulo TF, Abreu DS, Bernhardt PV, Gilles-Gonzalez MA, Cirino Nogueira Diógenes I, Henrique Silva Sousa E. Bioinorganic systems responsive to the diatomic gases O2, NO, and CO: From biological sensors to therapy. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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4
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Armstrong FA. Some fundamental insights into biological redox catalysis from the electrochemical characteristics of enzymes attached directly to electrodes. Electrochim Acta 2021; 390:138836. [PMID: 34511630 PMCID: PMC8386245 DOI: 10.1016/j.electacta.2021.138836] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/21/2021] [Accepted: 06/21/2021] [Indexed: 01/03/2023]
Abstract
This article outlines examples of where electrochemical investigations of electrocatalysis by proteins immobilised on an electrode reveal fundamental information about electron-proton coupling in catalysis and provide a new way to energise, control and observe multi-enzyme cascades.
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5
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Le H, Compton RG. Electrochemical processes mediated via adsorbed Enzymes: Flat and porous electrodes Compared. Understanding Nano-confinement. J Electroanal Chem (Lausanne) 2021. [DOI: 10.1016/j.jelechem.2021.115448] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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6
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STM studies of electron transfer through single molecules at electrode-electrolyte interfaces. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.138497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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7
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Direct Electrochemical Enzyme Electron Transfer on Electrodes Modified by Self-Assembled Molecular Monolayers. Catalysts 2020. [DOI: 10.3390/catal10121458] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Self-assembled molecular monolayers (SAMs) have long been recognized as crucial “bridges” between redox enzymes and solid electrode surfaces, on which the enzymes undergo direct electron transfer (DET)—for example, in enzymatic biofuel cells (EBFCs) and biosensors. SAMs possess a wide range of terminal groups that enable productive enzyme adsorption and fine-tuning in favorable orientations on the electrode. The tunneling distance and SAM chain length, and the contacting terminal SAM groups, are the most significant controlling factors in DET-type bioelectrocatalysis. In particular, SAM-modified nanostructured electrode materials have recently been extensively explored to improve the catalytic activity and stability of redox proteins immobilized on electrochemical surfaces. In this report, we present an overview of recent investigations of electrochemical enzyme DET processes on SAMs with a focus on single-crystal and nanoporous gold electrodes. Specifically, we consider the preparation and characterization methods of SAMs, as well as SAM applications in promoting interfacial electrochemical electron transfer of redox proteins and enzymes. The strategic selection of SAMs to accord with the properties of the core redox protein/enzymes is also highlighted.
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Zeng D, Salvatore P, Karlsen KK, Zhang J, Wengel J, Ulstrup J. Reprint of "Electrochemical intercalator binding to single- and double-strand DNA- and LNA-based molecules on Au(111)-electrode surfaces". J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2020.114527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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9
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Zeng D, Salvatore P, Karlsen KK, Zhang J, Wengel J, Ulstrup J. Electrochemical intercalator binding to single- and double-strand DNA- and LNA-based molecules on Au(111)-electrode surfaces. J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2020.114138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Zigah D, Lojou E, Poulpiquet A. Micro‐ and Nanoscopic Imaging of Enzymatic Electrodes: A Review. ChemElectroChem 2019. [DOI: 10.1002/celc.201901065] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Dodzi Zigah
- Univ. Bordeaux, CNRSBordeaux INP ISM UMR 5255 33400 Talence France
| | - Elisabeth Lojou
- Aix-Marseille Univ., CNRSBIP, UMR 7281 31 Chemin Aiguier 13009 Marseille France
| | - Anne Poulpiquet
- Aix-Marseille Univ., CNRSBIP, UMR 7281 31 Chemin Aiguier 13009 Marseille France
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11
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Zhang L, Ulstrup J, Zhang J. Voltammetry and molecular assembly of G-quadruplex DNAzyme on single-crystal Au(111)-electrode surfaces - hemin as an electrochemical intercalator. Faraday Discuss 2018; 193:99-112. [PMID: 27722546 DOI: 10.1039/c6fd00091f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
DNA quadruplexes (qs) are a class of "non-canonical" oligonucleotides (OGNs) composed of stacked guanine (G) quartets stabilized by specific cations. Metal porphyrins selectively bind to G-qs complexes to form what is known as DNAzyme, which can exhibit peroxidase and other catalytic activity similar to heme group metalloenzymes. In the present study we investigate the electrochemical properties and the structure of DNAzyme monolayers on single-crystal Au(111)-electrode surfaces using cyclic voltammetry and scanning tunnelling microscopy under electrochemical potential control (in situ STM). The target DNAzyme is formed from a single-strand OGN with 12 guanines and iron(iii) porphyrin IX (hemin), and assembles on Au(111) through a mercapto alkyl linker. The DNAzyme monolayers exhibit a strong pair of redox peaks at 0.0 V (NHE) at pH 7 in acetate buffer, shifted positively by about 50 mV compared to free hemin weakly physisorbed on the Au(111)-electrode surface. The voltammetric hemin signal of DNAzyme is enhanced 15 times compared with that of hemin adsorbed directly on the Au(111)-electrode surface. This is indicative of both the formation of a close to dense DNAzyme monolayer and that hemin is strongly bound to the immobilized 12G-qs in well-defined orientation favorable for interfacial ET with a rate constant of 6.0 ± 0.4 s-1. This is supported by in situ STM which discloses single-molecule G-quartet structures with a size of 1.6 ± 0.2 nm.
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Affiliation(s)
- Ling Zhang
- Department of Chemistry, Technical University of Denmark, Building 207, Kemitorvet, DK-2800 Kgs. Lyngby, Denmark.
| | - Jens Ulstrup
- Department of Chemistry, Technical University of Denmark, Building 207, Kemitorvet, DK-2800 Kgs. Lyngby, Denmark.
| | - Jingdong Zhang
- Department of Chemistry, Technical University of Denmark, Building 207, Kemitorvet, DK-2800 Kgs. Lyngby, Denmark.
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12
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Monteiro T, Almeida MG. Electrochemical Enzyme Biosensors Revisited: Old Solutions for New Problems. Crit Rev Anal Chem 2018; 49:44-66. [PMID: 29757683 DOI: 10.1080/10408347.2018.1461552] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Worldwide legislation is driving the development of novel and highly efficient analytical tools for assessing the composition of every material that interacts with Consumers or Nature. The biosensor technology is one of the most active R&D domains of Analytical Sciences focused on the challenge of taking analytical chemistry to the field. Electrochemical biosensors based on redox enzymes, in particular, are highly appealing due to their usual quick response, high selectivity and sensitivity, low cost and portable dimensions. This review paper aims to provide an overview of the most important advances made in the field since the proposal of the first biosensor, the well-known hand-held glucose meter. The first section addresses the current needs and challenges for novel analytical tools, followed by a brief description of the different components and configurations of biosensing devices, and the fundamentals of enzyme kinetics and amperometry. The following sections emphasize on enzyme-based amperometric biosensors and the different stages of their development.
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Affiliation(s)
- Tiago Monteiro
- a UCIBIO-REQUIMTE, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa , Caparica , Portugal
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13
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Novak D, Mojovic M, Pavicevic A, Zatloukalova M, Hernychova L, Bartosik M, Vacek J. Electrochemistry and electron paramagnetic resonance spectroscopy of cytochrome c and its heme-disrupted analogs. Bioelectrochemistry 2018; 119:136-141. [DOI: 10.1016/j.bioelechem.2017.09.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 09/19/2017] [Accepted: 09/19/2017] [Indexed: 11/30/2022]
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14
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Approaches to single-molecule studies of metalloprotein electron transfer using scanning probe-based techniques. Biochem Soc Trans 2017; 46:1-9. [DOI: 10.1042/bst20170229] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 11/17/2017] [Accepted: 11/21/2017] [Indexed: 01/30/2023]
Abstract
The single-molecule properties of metalloproteins have provided an intensely active research area in recent years. This brief review covers some of the techniques used to prepare, measure and analyse the electron transfer properties of metalloproteins, concentrating on scanning tunnelling microscopy-based techniques and advances in attachment of proteins to electrodes.
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15
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Matsunaga S, Yamada T, Kobayashi T, Kawai M. Scanning tunneling microscope observation of the phosphatidylserine domains in the phosphatidylcholine monolayer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:5449-5455. [PMID: 25913903 DOI: 10.1021/acs.langmuir.5b00859] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A mixed monolayer of 1,2-dihexanoyl-sn-glycero-3-phospho-l-serine (DHPS) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) on an 1-octanethiol-modified gold substrate was visualized on the nanometer scale using in situ scanning tunneling microscopy (STM) in aqueous solution. DHPS clusters were evident as spotty domains. STM enabled us to distinguish DHPS molecules from DHPC molecules depending on their electronic structures. The signal of the DHPS domains was abolished by neutralization with Ca(2+). The addition of the PS + Ca(2+)-binding protein of annexin V to the Ca(2+)-treated monolayer gave a number of spots corresponding to a single annexin V molecule.
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Affiliation(s)
- Soichiro Matsunaga
- †Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Taro Yamada
- ‡Lipid Biology Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Toshihide Kobayashi
- ‡Lipid Biology Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Maki Kawai
- †Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
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16
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Paleček E, Tkáč J, Bartošík M, Bertók T, Ostatná V, Paleček J. Electrochemistry of nonconjugated proteins and glycoproteins. Toward sensors for biomedicine and glycomics. Chem Rev 2015; 115:2045-108. [PMID: 25659975 PMCID: PMC4360380 DOI: 10.1021/cr500279h] [Citation(s) in RCA: 214] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Indexed: 02/07/2023]
Affiliation(s)
- Emil Paleček
- Institute
of Biophysics Academy of Science of the Czech Republic, v.v.i., Královopolská
135, 612 65 Brno, Czech Republic
| | - Jan Tkáč
- Institute
of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 38 Bratislava, Slovakia
| | - Martin Bartošík
- Regional
Centre for Applied Molecular Oncology, Masaryk
Memorial Cancer Institute, Žlutý kopec 7, 656 53 Brno, Czech Republic
| | - Tomáš Bertók
- Institute
of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 38 Bratislava, Slovakia
| | - Veronika Ostatná
- Institute
of Biophysics Academy of Science of the Czech Republic, v.v.i., Královopolská
135, 612 65 Brno, Czech Republic
| | - Jan Paleček
- Central
European Institute of Technology, Masaryk
University, Kamenice
5, 625 00 Brno, Czech Republic
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17
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Salvatore P, Nazmutdinov RR, Ulstrup J, Zhang J. DNA Bases Assembled on the Au(110)/Electrolyte Interface: A Combined Experimental and Theoretical Study. J Phys Chem B 2015; 119:3123-34. [DOI: 10.1021/jp511909f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Princia Salvatore
- Department
of Chemistry, Building 207, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Renat R. Nazmutdinov
- Kazan National
Research Technological University, K. Marx Str., 68, 420015 Kazan, Republic of Tatarstan, Russian Federation
| | - Jens Ulstrup
- Department
of Chemistry, Building 207, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Jingdong Zhang
- Department
of Chemistry, Building 207, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
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18
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Bacharouche J, Degardin M, Jierry L, Carteret C, Lavalle P, Hemmerlé J, Senger B, Auzély-Velty R, Boulmedais F, Boturyn D, Coche-Guérente L, Schaaf P, Francius G. Multivalency: influence of the residence time and the retraction rate on rupture forces measured by AFM. J Mater Chem B 2015; 3:1801-1812. [DOI: 10.1039/c4tb01261e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molecular orientation and flexibility of β-CD modulate the contact time and the multivalence effects of specific host–guest interactions.
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Mathwig K, Aartsma TJ, Canters GW, Lemay SG. Nanoscale methods for single-molecule electrochemistry. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2014; 7:383-404. [PMID: 25000819 DOI: 10.1146/annurev-anchem-062012-092557] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The development of experiments capable of probing individual molecules has led to major breakthroughs in fields ranging from molecular electronics to biophysics, allowing direct tests of knowledge derived from macroscopic measurements and enabling new assays that probe population heterogeneities and internal molecular dynamics. Although still somewhat in their infancy, such methods are also being developed for probing molecular systems in solution using electrochemical transduction mechanisms. Here we outline the present status of this emerging field, concentrating in particular on optical methods, metal-molecule-metal junctions, and electrochemical nanofluidic devices.
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Affiliation(s)
- Klaus Mathwig
- MESA+ Institute for Nanotechnology, University of Twente, 7500 AE Enschede, the Netherlands; ,
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20
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Di Rocco G, Ranieri A, Bortolotti CA, Battistuzzi G, Bonifacio A, Sergo V, Borsari M, Sola M. Axial iron coordination and spin state change in a heme c upon electrostatic protein-SAM interaction. Phys Chem Chem Phys 2014; 15:13499-505. [PMID: 23824165 DOI: 10.1039/c3cp50222h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A bacterial di-heme cytochrome c binds electrostatically to a gold electrode surface coated with a negatively charged COOH-terminated SAM adopting a sort of 'perpendicular' orientation. Cyclic voltammetry, Resonance Raman and SERRS spectroscopies indicate that the high-potential C-terminal heme center proximal to the SAM's surface undergoes an adsorption-induced swapping of one axial His ligand with a water molecule, which is probably lost in the reduced form, and a low- to high-spin transition. This coordination change for a bis-His ligated heme center upon an electrostatically-driven molecular recognition is as yet unprecedented, as well as the resulting increase in reduction potential. We discuss it in comparison with the known methionine ligand lability in monoheme cytochromes c occurring upon interaction with charged molecular patches. One possible implication of this finding in biological ET is that mobile redox partners do not behave as rigid and invariant bodies, but in the ET complex are subjected to molecular changes and structural fluctuations that affect in a complex way the thermodynamics and the kinetics of the process.
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Affiliation(s)
- Giulia Di Rocco
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 183, I-41125 Modena, Italy
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21
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Darwish N, Paddon-Row MN, Gooding JJ. Surface-bound norbornylogous bridges as molecular rulers for investigating interfacial electrochemistry and as single molecule switches. Acc Chem Res 2014; 47:385-95. [PMID: 24160945 DOI: 10.1021/ar400127g] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Electron transfer (ET) reactions through molecules attached to surfaces, whether they are through single molecules or ensembles, are the subject of much research in molecular electronics, bioelectronics, and electrochemistry. Therefore, understanding the factors that govern ET is of high importance. The availability of rigid hydrocarbon molecular scaffolds possessing well-defined configurations and lengths that can be systematically varied is crucial to the development of such devices. In this Account, we demonstrate how suitably functionalized norbornylogous (NB) systems can provide important insights into interfacial ET processes and electrical conduction through single molecules. To this end, we created NB bridges with vic-trans-bismethylenethiol groups at one end so they can assemble on gold electrodes and redox species at the distal ends. With these in hand, we then formed mixed self-assembled monolayers (SAMs) containing a small proportion of the NB bridges diluted with alkanethiols. As such, the NB bridges served as molecular rulers for probing the environment above the surface defined by the diluent species. Using this construct, we were able to measure the interfacial potential distribution above the diluent surface, and track how variation in the ionic distribution in the electrical double layer impacts ET kinetics. Using the same construct, but with a redox molecule that remains neutral in both oxidized and reduced states, we could explore the impact of the chemical environment near a surface on ET processes. These results are important, because with conventional surface constructs, ET occurs across this interfacial region. Such knowledge is therefore relevant to the design of molecular systems at surfaces involving ET. With a second family of molecules, we investigated aspects of single-molecule electrical conduction using NB bridges bearing vic-trans-bismethylenethiol groups at both ends of the bridge. This gave us insights into distance-dependent electron transport through single molecules and introduced a method of boosting the conductance of saturated molecules by incorporating aromatic moieties in their backbone. These partially conjugated NB molecules represent a new class of molecular wires with far greater stability than conventional completely conjugated molecular wires. Of particular note was our demonstration of a single molecule switch, using a NB bridge containing an embedded anthraquinone redox group, the switching mechanism being via electrochemically controlled quantum interference.
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Affiliation(s)
- Nadim Darwish
- School of Chemistry, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Michael N. Paddon-Row
- School of Chemistry, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - J. Justin Gooding
- School of Chemistry, The University of New South Wales, Sydney, New South Wales 2052, Australia
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22
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Reconstitution of supramolecular organization involved in energy metabolism at electrochemical interfaces for biosensing and bioenergy production. Anal Bioanal Chem 2013; 406:1011-27. [DOI: 10.1007/s00216-013-7465-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 10/01/2013] [Accepted: 10/25/2013] [Indexed: 12/26/2022]
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23
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Chen P, Keller AM, Joshi CP, Martell DJ, Andoy NM, Benítez JJ, Chen TY, Santiago AG, Yang F. Single-molecule dynamics and mechanisms of metalloregulators and metallochaperones. Biochemistry 2013; 52:7170-83. [PMID: 24053279 DOI: 10.1021/bi400597v] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Understanding how cells regulate and transport metal ions is an important goal in the field of bioinorganic chemistry, a frontier research area that resides at the interface of chemistry and biology. This Current Topic reviews recent advances from the authors' group in using single-molecule fluorescence imaging techniques to identify the mechanisms of metal homeostatic proteins, including metalloregulators and metallochaperones. It emphasizes the novel mechanistic insights into how dynamic protein-DNA and protein-protein interactions offer efficient pathways via which MerR-family metalloregulators and copper chaperones can fulfill their functions. This work also summarizes other related single-molecule studies of bioinorganic systems and provides an outlook toward single-molecule imaging of metalloprotein functions in living cells.
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Affiliation(s)
- Peng Chen
- Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
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24
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Pheeney CG, Arnold AR, Grodick MA, Barton JK. Multiplexed electrochemistry of DNA-bound metalloproteins. J Am Chem Soc 2013; 135:11869-78. [PMID: 23899026 DOI: 10.1021/ja4041779] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Here we describe a multiplexed electrochemical characterization of DNA-bound proteins containing [4Fe-4S] clusters. DNA-modified electrodes have become an essential tool for the characterization of the redox chemistry of DNA repair proteins containing redox cofactors, and multiplexing offers a means to probe different complex samples and substrates in parallel to elucidate this chemistry. Multiplexed analysis of endonuclease III (EndoIII), a DNA repair protein containing a [4Fe-4S] cluster known to be accessible via DNA-mediated charge transport, shows subtle differences in the electrochemical behavior as a function of DNA morphology. The peak splitting, signal broadness, sensitivity to π-stack perturbations, and kinetics were all characterized for the DNA-bound reduction of EndoIII on both closely and loosely packed DNA films. DNA-bound EndoIII is seen to have two different electron transfer pathways for reduction, either through the DNA base stack or through direct surface reduction; closely packed DNA films, where the protein has limited surface accessibility, produce electrochemical signals reflecting electron transfer that is DNA-mediated. Multiplexing furthermore permits the comparison of the electrochemistry of EndoIII mutants, including a new family of mutations altering the electrostatics surrounding the [4Fe-4S] cluster. While little change in the midpoint potential was found for this family of mutants, significant variations in the efficiency of DNA-mediated electron transfer were apparent. On the basis of the stability of these proteins, examined by circular dichroism, we propose that the electron transfer pathway can be perturbed not only by the removal of aromatic residues but also through changes in solvation near the cluster.
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Affiliation(s)
- Catrina G Pheeney
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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25
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Salvatore P, Zeng D, Karlsen KK, Chi Q, Wengel J, Ulstrup J. Electrochemistry of single metalloprotein and DNA-based molecules at Au(111) electrode surfaces. Chemphyschem 2013; 14:2101-11. [PMID: 23788363 DOI: 10.1002/cphc.201300299] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Indexed: 11/10/2022]
Abstract
We have briefly overviewed recent efforts in the electrochemistry of single transition metal complex, redox metalloprotein, and redox-marked oligonucleotide (ON) molecules. We have particularly studied self-assembled molecular monolayers (SAMs) of several 5'-C6-SH single- (ss) and double-strand (ds) ONs immobilized on Au(111) electrode surfaces via Au-S bond formation, using a combination of nucleic acid chemistry, electrochemistry and electrochemically controlled scanning tunnelling microscopy (in situ STM). Ds ONs stabilized by multiply charged cations and locked nucleic acid (LNA) monomers have been primary targets, with a view on stabilizing the ds-ONs and improving voltammetric signals of intercalating electrochemical redox probes. Voltammetric signals of the intercalator anthraquinone monosulfonate (AQMS) at ds-DNA/Au(111) surfaces diluted by mercaptohexanol are significantly sharpened and more robust in the presence than in the absence of [Co(NH3)6](3+). AQMS also displays robust Faradaic voltammetric signals specific to the ds form on binding to similar LNA/Au(111) surfaces, but this signal only evolves after successive voltammetric scanning into negative potential ranges. Triply charged spermidine (Spd) invokes itself a strong voltammetric signal, which is specific to the ds form and fully matched sequences. This signal is of non-Faradaic, capacitive origin but appears in the same potential range as the Faradaic AQMS signal. In situ STM shows that molecular scale structures of the size of Spd-stabilized ds-ONs are densely packed over the Au(111) surface in potential ranges around the capacitive peak potential.
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Affiliation(s)
- Princia Salvatore
- Department of Chemistry, Kemitorvet, Building 207, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
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Marmisollé WA, Capdevila DA, de la Llave E, Williams FJ, Murgida DH. Self-assembled monolayers of NH2-terminated thiolates: order, pKa, and specific adsorption. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:5351-5359. [PMID: 23560885 DOI: 10.1021/la304730q] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Self-assembled monolayers (SAMs) of amino-terminated alkanethiols on Au were characterized by a combination of electrochemical (LSV, CV, and EIS) and spectroscopic (XPS and SER) techniques. Clear correlations were obtained between the apparent surface pKa values determined by impedimetric titrations and order parameters such as the content of trans conformers in the SAMs. These results contrast with previous studies that exhibit dispersions of up to 6 pH units in the reported pKa values. In addition, we determined that inorganic and organic phosphate species bind specifically to these SAMs mediating adsorption and heterogeneous electron transfer of positively charged macromolecules such as cytochrome c.
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Affiliation(s)
- Waldemar A Marmisollé
- Departamento de Química Inorgánica, Analítica y Química Física and INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and CONICET, Ciudad Universitaria, pab. 2, piso 3, C1428EHA-Buenos Aires, Argentina
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Hao X, Zhang J, Christensen HEM, Wang H, Ulstrup J. Electrochemical Single-Molecule AFM of the Redox Metalloenzyme Copper Nitrite Reductase in Action. Chemphyschem 2012; 13:2919-24. [DOI: 10.1002/cphc.201200220] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Indexed: 11/11/2022]
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