1
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Baptista FA, Krizsan D, Stitch M, Sazanovich IV, Clark IP, Towrie M, Long C, Martinez-Fernandez L, Improta R, Kane-Maguire NAP, Kelly JM, Quinn SJ. Adenine Radical Cation Formation by a Ligand-Centered Excited State of an Intercalated Chromium Polypyridyl Complex Leads to Enhanced DNA Photo-oxidation. J Am Chem Soc 2021; 143:14766-14779. [PMID: 34464120 PMCID: PMC8447253 DOI: 10.1021/jacs.1c06658] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
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Assessment of the
DNA photo-oxidation and synthetic photocatalytic
activity of chromium polypyridyl complexes is dominated by consideration
of their long-lived metal-centered excited states. Here we report
the participation of the excited states of [Cr(TMP)2dppz]3+ (1) (TMP = 3,4,7,8-tetramethyl-1,10-phenanthroline;
dppz = dipyrido[3,2-a:2′,3′-c]phenazine) in DNA photoreactions. The interactions of
enantiomers of 1 with natural DNA or with oligodeoxynucleotides
with varying AT content (0–100%) have been studied by steady
state UV/visible absorption and luminescence spectroscopic methods,
and the emission of 1 is found to be quenched in all
systems. The time-resolved infrared (TRIR) and visible absorption
spectra (TA) of 1 following excitation in the region
between 350 to 400 nm reveal the presence of relatively long-lived
dppz-centered states which eventually yield the emissive metal-centered
state. The dppz-localized states are fully quenched when bound by
GC base pairs and partially so in the presence of an AT base-pair
system to generate purine radical cations. The sensitized formation
of the adenine radical cation species (A•+T) is identified by assigning the TRIR spectra with help of
DFT calculations. In natural DNA and oligodeoxynucleotides containing
a mixture of AT and GC of base pairs, the observed time-resolved spectra
are consistent with eventual photo-oxidation occurring predominantly
at guanine through hole migration between base pairs. The combined
targeting of purines leads to enhanced photo-oxidation of guanine.
These results show that DNA photo-oxidation by the intercalated 1, which locates the dppz in contact with the target purines,
is dominated by the LC centered excited state. This work has implications
for future phototherapeutics and photocatalysis.
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Affiliation(s)
| | - Dorottya Krizsan
- School of Chemistry, University College Dublin, Dublin 4, Ireland
| | - Mark Stitch
- School of Chemistry, University College Dublin, Dublin 4, Ireland
| | - Igor V Sazanovich
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, U.K
| | - Ian P Clark
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, U.K
| | - Michael Towrie
- STFC Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, U.K
| | - Conor Long
- The School of Chemical Sciences, Dublin City University, Dublin 9, Ireland
| | - Lara Martinez-Fernandez
- Departamento de Química, Facultad de Ciencias and Institute for Advanced Research in Chemistry(IADCHEM) Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC, Cantoblanco, 28049 Madrid, Spain
| | - Roberto Improta
- Consiglio Nazionale delle Ricerche, Istituto di Biostrutture e Bioimmagini, 80136 Naples, Italy
| | - Noel A P Kane-Maguire
- Department of Chemistry, Furman University, 3300 Poinsett Highway, Greenville, South Carolina 29613-1120, United States
| | - John M Kelly
- School of Chemistry, Trinity College Dublin, The University of Dublin, Dublin 2, Ireland
| | - Susan J Quinn
- School of Chemistry, University College Dublin, Dublin 4, Ireland
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2
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Sobek J, Schmidt M, Grossmann J, Rehrauer H, Schmidt L, Schlapbach R. Single-molecule chemistry. Part I: monitoring oxidation of G in oligonucleotides using CY3 fluorescence. Methods Appl Fluoresc 2020; 8:035010. [PMID: 32428873 DOI: 10.1088/2050-6120/ab947d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Single-molecule hybridisation of CY3 dye labelled short oligonucleotides to surface immobilised probes was investigated in zero-mode waveguide nanostructures using a modified DNA sequencer. At longer measuring times, we observed changes of the initial hybridisation fluorescence pulse pattern which we attribute to products created by chemical reactions at the nucleobases. The origin is a charge separated state created by a photoinduced electron transfer from nucleobases to the dye followed by secondary reactions with oxygen and water, respectively. The positive charge can migrate through the hybrid resulting in base modifications at distant sites. Static fluorescence spectra were recorded in order to determine the properties of CY3 stacking to different base pairs, and compared to pulse intensities. A characteristic pulse pattern change was assigned to the oxidation of G to 8-oG besides the formation of a number of secondary products that are not yet identified. Further, we present a method to visualise the degree of chemical reactions to gain an overview of ongoing processes. Our study demonstrates that CY3 is able to oxidise nucleobases in ds DNA, and also in ss overhangs. An important finding is the correlation between nucleobase oxidation potential and fluorescence quenching which explains the intensity changes observed in single molecule measurements. The analysis of fluorescence traces provides the opportunity to track complete and coherent reaction sequences enabling to follow the fate of a single molecule over a long period of time, and to observe chemical reactions in real-time. This opens up the opportunity to analyse reaction pathways, to detect new products and short-lived intermediates, and to investigate rare events due to the large number of single molecules observed in parallel.
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Affiliation(s)
- Jens Sobek
- Functional Genomics Center Zurich, Eidgenössische Technische Hochschule (ETH) Zurich and University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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3
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Harris MA, Mishra AK, Young RM, Brown KE, Wasielewski MR, Lewis FD. Direct Observation of the Hole Carriers in DNA Photoinduced Charge Transport. J Am Chem Soc 2016; 138:5491-4. [DOI: 10.1021/jacs.6b00702] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Michelle A. Harris
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ashutosh Kumar Mishra
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M. Young
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Kristen E. Brown
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Frederick D. Lewis
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
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4
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Liu C, Beratan DN, Zhang P. Coarse-Grained Theory of Biological Charge Transfer with Spatially and Temporally Correlated Noise. J Phys Chem B 2016; 120:3624-33. [DOI: 10.1021/acs.jpcb.6b01018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Chaoren Liu
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - David N. Beratan
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
- Departments
of Biochemistry and Physics, Duke University, Durham, North Carolina 27708, United States
| | - Peng Zhang
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
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5
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Nenov A, Segarra-Martí J, Giussani A, Conti I, Rivalta I, Dumont E, Jaiswal VK, Altavilla SF, Mukamel S, Garavelli M. Probing deactivation pathways of DNA nucleobases by two-dimensional electronic spectroscopy: first principles simulations. Faraday Discuss 2015; 177:345-62. [PMID: 25607949 DOI: 10.1039/c4fd00175c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The SOS//QM/MM [Rivalta et al., Int. J. Quant. Chem., 2014, 114, 85] method consists of an arsenal of computational tools allowing accurate simulation of one-dimensional (1D) and bi-dimensional (2D) electronic spectra of monomeric and dimeric systems with unprecedented details and accuracy. Prominent features like doubly excited local and excimer states, accessible in multi-photon processes, as well as charge-transfer states arise naturally through the fully quantum-mechanical description of the aggregates. In this contribution the SOS//QM/MM approach is extended to simulate time-resolved 2D spectra that can be used to characterize ultrafast excited state relaxation dynamics with atomistic details. We demonstrate how critical structures on the excited state potential energy surface, obtained through state-of-the-art quantum chemical computations, can be used as snapshots of the excited state relaxation dynamics to generate spectral fingerprints for different de-excitation channels. The approach is based on high-level multi-configurational wavefunction methods combined with non-linear response theory and incorporates the effects of the solvent/environment through hybrid quantum mechanics/molecular mechanics (QM/MM) techniques. Specifically, the protocol makes use of the second-order Perturbation Theory (CASPT2) on top of Complete Active Space Self Consistent Field (CASSCF) strategy to compute the high-lying excited states that can be accessed in different 2D experimental setups. As an example, the photophysics of the stacked adenine-adenine dimer in a double-stranded DNA is modeled through 2D near-ultraviolet (NUV) spectroscopy.
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Affiliation(s)
- Artur Nenov
- Dipartimento di Chimica G. Ciamician, Università di Bologna, Via F. Selmi 2, 40126 Bologna, Italy.
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6
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Zhang Y, Young RM, Thazhathveetil AK, Singh APN, Liu C, Berlin YA, Grozema FC, Lewis FD, Ratner MA, Renaud N, Siriwong K, Voityuk AA, Wasielewski MR, Beratan DN. Conformationally Gated Charge Transfer in DNA Three-Way Junctions. J Phys Chem Lett 2015; 6:2434-2438. [PMID: 26266714 DOI: 10.1021/acs.jpclett.5b00863] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Molecular structures that direct charge transport in two or three dimensions possess some of the essential functionality of electrical switches and gates. We use theory, modeling, and simulation to explore the conformational dynamics of DNA three-way junctions (TWJs) that may control the flow of charge through these structures. Molecular dynamics simulations and quantum calculations indicate that DNA TWJs undergo dynamic interconversion among "well stacked" conformations on the time scale of nanoseconds, a feature that makes the junctions very different from linear DNA duplexes. The studies further indicate that this conformational gating would control charge flow through these TWJs, distinguishing them from conventional (larger size scale) gated devices. Simulations also find that structures with polyethylene glycol linking groups ("extenders") lock conformations that favor CT for 25 ns or more. The simulations explain the kinetics observed experimentally in TWJs and rationalize their transport properties compared with double-stranded DNA.
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Affiliation(s)
- Yuqi Zhang
- †Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Ryan M Young
- ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- §Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208, United States
| | - Arun K Thazhathveetil
- ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Arunoday P N Singh
- ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Chaoren Liu
- †Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Yuri A Berlin
- ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Ferdinand C Grozema
- ∥DelftChemTech, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands
| | - Frederick D Lewis
- ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Mark A Ratner
- ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Nicolas Renaud
- ∥DelftChemTech, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands
| | - Khatcharin Siriwong
- ⊥Materials Chemistry Research Center, Department of Chemistry and Center for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Alexander A Voityuk
- #Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain, Institut de Química Computacional, Universitat de Girona, 17071 Girona, Spain
| | - Michael R Wasielewski
- ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- §Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208, United States
| | - David N Beratan
- †Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
- ▽Departments of Biochemistry and Physics, Duke University, Durham, North Carolina 27708, United States
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7
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Young RM, Singh APN, Thazhathveetil AK, Cho VY, Zhang Y, Renaud N, Grozema FC, Beratan DN, Ratner MA, Schatz GC, Berlin YA, Lewis FD, Wasielewski MR. Charge Transport across DNA-Based Three-Way Junctions. J Am Chem Soc 2015; 137:5113-22. [DOI: 10.1021/jacs.5b00931] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Ryan M. Young
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
- Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Arunoday P. N. Singh
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Arun K. Thazhathveetil
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Vincent Y. Cho
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Yuqi Zhang
- Departments
of Chemistry, Biochemistry, and Physics, Duke University
, Durham, North Carolina
27708, United States
| | - Nicolas Renaud
- DelftChemTech, Delft University of Technology
, Julianalaan 136, 2628 BL
Delft, The Netherlands
| | - Ferdinand C. Grozema
- DelftChemTech, Delft University of Technology
, Julianalaan 136, 2628 BL
Delft, The Netherlands
| | - David N. Beratan
- Departments
of Chemistry, Biochemistry, and Physics, Duke University
, Durham, North Carolina
27708, United States
| | - Mark A. Ratner
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - George C. Schatz
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Yuri A. Berlin
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Frederick D. Lewis
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Michael R. Wasielewski
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
- Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University
, Evanston, Illinois
60208-3113, United States
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8
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Singh APN, Harris MA, Young RM, Miller SA, Wasielewski MR, Lewis FD. Raising the barrier for photoinduced DNA charge injection with a cyclohexyl artificial base pair. Faraday Discuss 2015; 185:105-20. [DOI: 10.1039/c5fd00043b] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The effects of an artificial cyclohexyl base pair on the quantum yields of fluorescence and dynamics of charge separation and charge recombination have been investigated for several synthetic DNA hairpins. The hairpins possess stilbenedicarboxamide, perylenediimide, or naphthalenediimide linkers and base-paired stems. In the absence of the artificial base pair hole injection into both adenine and guanine purine bases is exergonic and irreversible, except in the case of stilbene with adenine for which it is slightly endergonic and reversible. Insertion of the artificial base pair renders hole injection endergonic or isoergonic except in the case of the powerful naphthalene acceptor for which it remains exergonic. Both hole injection and charge recombination are slower for the naphthalene acceptor in the presence of the artificial base pair than in its absence. The effect of an artificial base pair on charge separation and charge recombination in hairpins possessing stilbene and naphthalene acceptor linkers and a stilbenediether donor capping group has also been investigated. In the case of the stilbene acceptor–stilbene donor capped hairpins photoinduced charge separation across six base pairs is efficient in the absence of the artificial base pair but does not occur in its presence. In the case of the naphthalene acceptor–stilbene donor capped hairpins the artificial base pair slows but does not stop charge separation and charge recombination, leading to the formation of long-lived charge separated states.
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Affiliation(s)
| | | | - Ryan M. Young
- Department of Chemistry
- Northwestern University
- Evanston
- USA
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9
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Mishra AK, Young RM, Wasielewski MR, Lewis FD. Wirelike Charge Transport Dynamics for DNA–Lipid Complexes in Chloroform. J Am Chem Soc 2014; 136:15792-7. [DOI: 10.1021/ja509456q] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ashutosh Kumar Mishra
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M. Young
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Frederick D. Lewis
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
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10
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Design and Applications of Nanomaterial-Based and Biomolecule-Based Nanodevices and Nanosensors. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/978-94-017-8848-9_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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11
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Abstract
Biological electron-transfer (ET) reactions are typically described in the framework of coherent two-state electron tunneling or multistep hopping. However, these ET reactions may involve multiple redox cofactors in van der Waals contact with each other and with vibronic broadenings on the same scale as the energy gaps among the species. In this regime, fluctuations of the molecular structures and of the medium can produce transient energy level matching among multiple electronic states. This transient degeneracy, or flickering electronic resonance among states, is found to support coherent (ballistic) charge transfer. Importantly, ET rates arising from a flickering resonance (FR) mechanism will decay exponentially with distance because the probability of energy matching multiple states is multiplicative. The distance dependence of FR transport thus mimics the exponential decay that is usually associated with electron tunneling, although FR transport involves real carrier population on the bridge and is not a tunneling phenomenon. Likely candidates for FR transport are macromolecules with ET groups in van der Waals contact: DNA, bacterial nanowires, multiheme proteins, strongly coupled porphyrin arrays, and proteins with closely packed redox-active residues. The theory developed here is used to analyze DNA charge-transfer kinetics, and we find that charge-transfer distances up to three to four bases may be accounted for with this mechanism. Thus, the observed rapid (exponential) distance dependence of DNA ET rates over distances of ≲ 15 Å does not necessarily prove a tunneling mechanism.
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12
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Impact of a single base pair substitution on the charge transfer rate along short DNA hairpins. Proc Natl Acad Sci U S A 2013; 110:14867-71. [PMID: 23980166 DOI: 10.1073/pnas.1309139110] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Numerical studies of hole migration along short DNA hairpins were performed with a particular emphasis on the variations of the rate and quantum yield of the charge separation process with the location of a single guanine:cytosine (G:C) base pair. Our calculations show that the hole arrival rate increases as the position of the guanine:cytosine base pair shifts from the beginning to the end of the sequence. Although these results are in agreement with recent experimental findings, the mechanism governing the charge migration along these sequences is revisited here. Instead of the phenomenological two-step hopping mechanism via the guanine base, the charge propagation occurs through a delocalization of the hole density along the base pair stack. Furthermore, the variations of the charge transfer with the position of the guanine base are explained by the impact of the base pair substitutions on the delocalized conduction channels.
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13
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Dynamics and efficiency of photoinduced charge transport in DNA: Toward the elusive molecular wire. PURE APPL CHEM 2013. [DOI: 10.1351/pac-con-13-01-09] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Experimental investigations of photoinduced charge transport in synthetic DNA
capped hairpins possessing electron acceptor and donor stilbene chromophores at
either end have established the mechanism, dynamics, and efficiency of charge
transport in DNA. The mechanism for charge transport in repeating A-T base pairs
(A-tracts) was found to change from single-step superexchange at short distances
to multistep incoherent hole hopping at longer distances. The rate constants for
base-to-base hole hopping in longer A- and G-tract sequences are 1.2
× 109 s–1 and 4.3 × 109 s–1,
respectively, considerably slower than the rate constants associated with
molecular wires. Even slower rate constants are observed for alternating or
random base sequences such as those encountered in natural DNA. The efficiency
of charge separation in capped hairpins with A-tract sequences is also low as a
consequence of the competition of hole hopping with charge recombination.
Significantly higher efficiencies for charge separation are possible using
diblock purine base sequences consisting of two or three adenines followed by a
larger number of guanines. The short A-block serves as a molecular rectifier,
slowing down charge recombination. More efficient charge separation can also be
achieved using non-natural bases or by using the triplet acceptor anthraquinone
for hole injection.
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14
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Lewis FD. Distance-Dependent Electronic Interactions Across DNA Base Pairs: Charge Transport, Exciton Coupling, and Energy Transfer. Isr J Chem 2013. [DOI: 10.1002/ijch.201300035] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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15
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Renaud N, Berlin YA, Lewis FD, Ratner MA. Between superexchange and hopping: an intermediate charge-transfer mechanism in poly(A)-poly(T) DNA hairpins. J Am Chem Soc 2013; 135:3953-63. [PMID: 23402652 DOI: 10.1021/ja3113998] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We developed a model for hole migration along relatively short DNA hairpins with fewer that seven adenine (A):thymine (T) base pairs. The model was used to simulate hole migration along poly(A)-poly(T) sequences with a particular emphasis on the impact of partial hole localization on the different rate processes. The simulations, performed within the framework of the stochastic surrogate Hamiltonian approach, give values for the arrival rate in good agreement with experimental data. Theoretical results obtained for hairpins with fewer than three A:T base pairs suggest that hole transfer along short hairpins occurs via superexchange. This mechanism is characterized by the exponential distance dependence of the arrival rate on the donor/acceptor distance, k(a) ≃ e(-βR), with β = 0.9 Å(-1). For longer systems, up to six A:T pairs, the distance dependence follows a power law k(a) ≃ R(-η) with η = 2. Despite this seemingly clear signature of unbiased hopping, our simulations show the complete delocalization of the hole density along the entire hairpin. According to our analysis, the hole transfer along relatively long sequences may proceed through a mechanism which is distinct from both coherent single-step superexchange and incoherent multistep hopping. The criterion for the validity of this mechanism intermediate between superexchange and hopping is proposed. The impact of partial localization on the rate of hole transfer between neighboring A bases was also investigated.
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Affiliation(s)
- Nicolas Renaud
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, USA.
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16
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Muren NB, Olmon ED, Barton JK. Solution, surface, and single molecule platforms for the study of DNA-mediated charge transport. Phys Chem Chem Phys 2012; 14:13754-71. [PMID: 22850865 PMCID: PMC3478128 DOI: 10.1039/c2cp41602f] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The structural core of DNA, a continuous stack of aromatic heterocycles, the base pairs, which extends down the helical axis, gives rise to the fascinating electronic properties of this molecule that is so critical for life. Our laboratory and others have developed diverse experimental platforms to investigate the capacity of DNA to conduct charge, termed DNA-mediated charge transport (DNA CT). Here, we present an overview of DNA CT experiments in solution, on surfaces, and with single molecules that collectively provide a broad and consistent perspective on the essential characteristics of this chemistry. DNA CT can proceed over long molecular distances but is remarkably sensitive to perturbations in base pair stacking. We discuss how this foundation, built with data from diverse platforms, can be used both to inform a mechanistic description of DNA CT and to inspire the next platforms for its study: living organisms and molecular electronics.
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Affiliation(s)
- Natalie B. Muren
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125, USA
| | - Eric D. Olmon
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125, USA
| | - Jacqueline K. Barton
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125, USA
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17
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Vayá I, Gustavsson T, Douki T, Berlin Y, Markovitsi D. Electronic Excitation Energy Transfer between Nucleobases of Natural DNA. J Am Chem Soc 2012; 134:11366-8. [DOI: 10.1021/ja304328g] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ignacio Vayá
- CNRS, IRAMIS, SPAM, Laboratoire
Francis Perrin, URA 2453, F-91191 Gif-sur-Yvette, France
| | - Thomas Gustavsson
- CNRS, IRAMIS, SPAM, Laboratoire
Francis Perrin, URA 2453, F-91191 Gif-sur-Yvette, France
| | - Thierry Douki
- CEA, INAC, SCIB, UJF & CNRS, LCIB (UMR_E 3 CEA-UJF and FRE 3200), Laboratoire “Lésions des Acides Nucléiques”, 17 Rue des Martyrs, F-38054 Grenoble Cedex 9, France
| | - Yuri Berlin
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston,
Illinois 60208-3113, United States
| | - Dimitra Markovitsi
- CNRS, IRAMIS, SPAM, Laboratoire
Francis Perrin, URA 2453, F-91191 Gif-sur-Yvette, France
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18
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Carmieli R, Smeigh AL, Mickley Conron SM, Thazhathveetil AK, Fuki M, Kobori Y, Lewis FD, Wasielewski MR. Structure and Dynamics of Photogenerated Triplet Radical Ion Pairs in DNA Hairpin Conjugates with Anthraquinone End Caps. J Am Chem Soc 2012; 134:11251-60. [DOI: 10.1021/ja303721j] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Raanan Carmieli
- Department of Chemistry and Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Amanda L. Smeigh
- Department of Chemistry and Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Sarah M. Mickley Conron
- Department of Chemistry and Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Arun K. Thazhathveetil
- Department of Chemistry and Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Masaaki Fuki
- Department of Chemistry, Faculty of Science, Shizuoka University, 836 Ohya Surugaku, Shizuoka 422-8529,
Japan
| | - Yasuhiro Kobori
- Department of Chemistry, Faculty of Science, Shizuoka University, 836 Ohya Surugaku, Shizuoka 422-8529,
Japan
- PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho
Kawaguchi, Saitama 332-0012, Japan
| | - Frederick D. Lewis
- Department of Chemistry and Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry and Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
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19
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Affiliation(s)
- Emil Paleček
- Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, 612
65 Brno, Czech Republic
| | - Martin Bartošík
- Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, 612
65 Brno, Czech Republic
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20
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Joseph J, Schuster GB. Oxidatively generated damage to DNA at 5-methylcytosine mispairs. Photochem Photobiol Sci 2012; 11:998-1003. [PMID: 22327601 DOI: 10.1039/c2pp05379a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Oxidatively generated damage to DNA has been implicated as causing mutations that lead to aging and disease. The one-electron oxidation of normal DNA leads to formation of a nucleobase radical cation that hops through the DNA until it is trapped irreversibly, primarily by reaction at guanine. It has been observed that 5-methylcytosine (C(m)) is a mutational "hot-spot". However, C(m) in a Watson-Crick base pair with G is not especially susceptible to oxidatively induced damage. Radical cation hopping is inhibited in duplexes that contain C-A or C-T mispairs, but no reaction is detected at cytosine. In contrast, we find that the one-electron oxidation of DNA that contains C(m)-A or C(m)-T mispairs results primarily in reaction at C(m) even in the presence of GG steps. The reaction at C(m) is attributed to proton coupled electron transfer, which provides a relatively low activation barrier path for reaction at 5-methylcytosine. This enhanced reactivity of C(m) in mispairs may contribute to the formation of mutational hot spots at C(m).
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Affiliation(s)
- Joshy Joseph
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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21
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Venkatramani R, Keinan S, Balaeff A, Beratan DN. Nucleic Acid Charge Transfer: Black, White and Gray. Coord Chem Rev 2011; 255:635-648. [PMID: 21528017 PMCID: PMC3081592 DOI: 10.1016/j.ccr.2010.12.010] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Theoretical studies of charge transport in deoxyribonucleic acid (DNA) and peptide nucleic acid (PNA) indicate that structure and dynamics modulate the charge transfer rates, and that different members of a structural ensemble support different charge transport mechanisms. Here, we review the influences of nucleobase geometry, electronic structure, solvent environment, and thermal conformational fluctuations on the charge transfer mechanism. We describe an emerging framework for understanding the diversity of charge transport mechanisms seen in nucleic acids.
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Affiliation(s)
| | - Shahar Keinan
- Department of Chemistry, Duke University, Durham, North Carolina 27708
| | - Alexander Balaeff
- Department of Chemistry, Duke University, Durham, North Carolina 27708
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22
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Kanvah S, Schuster GB. Effect of positively charged backbone groups on radical cation migration and reaction in duplex DNA. CAN J CHEM 2011. [DOI: 10.1139/v10-145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A series of DNA oligomers were prepared that contain guanidinium linkages (positively charged) positioned selectively in place of and among the normal negatively charged phosphodiester backbone groups of duplex DNA. One-electron oxidation of these DNA oligomers by UV irradiation of a covalently linked anthraquinone group generates a radical cation (electron “hole”) that migrates by hopping through the DNA and is trapped at reactive sites, GG steps, to form mutated bases that are detected by strand cleavage after subsequent piperidine treatment of the irradiated DNA. Analysis of the strand cleavage pattern reveals that guanidinium substitution in these oligomers does not measurably affect the charge migration rate but it does inhibit reaction at nearby guanines.
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Affiliation(s)
- Sriram Kanvah
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Gary B. Schuster
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
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23
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Voityuk AA, Siriwong K, Berlin YA. Effects of various halogen anions and cations of alkali metals on energetics of excess charge recombination in stilbene donor–acceptor capped DNA hairpins. Phys Chem Chem Phys 2011; 13:16028-32. [DOI: 10.1039/c1cp21056d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Blaustein GS, Lewis FD, Burin AL. Kinetics of Charge Separation in Poly(A)−Poly(T) DNA Hairpins. J Phys Chem B 2010; 114:6732-9. [DOI: 10.1021/jp101328t] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Gail S. Blaustein
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, and Department of Northwestern University, Evanston, Illinois 60208
| | - Frederick D. Lewis
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, and Department of Northwestern University, Evanston, Illinois 60208
| | - Alexander L. Burin
- Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, and Department of Northwestern University, Evanston, Illinois 60208
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25
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Pavanello M, Adamowicz L, Volobuyev M, Mennucci B. Modeling Hole Transport in Wet and Dry DNA. J Phys Chem B 2010; 114:4416-23. [DOI: 10.1021/jp9099094] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Michele Pavanello
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona
| | - Ludwik Adamowicz
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona
| | - Maksym Volobuyev
- Department of Chemistry, Kharkiv Polytechnical Institute, Kharkiv, Ukraine
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Pisa, Italy
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26
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Affiliation(s)
- Joseph C. Genereux
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Jacqueline K. Barton
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
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27
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Kanvah S, Joseph J, Schuster GB, Barnett RN, Cleveland CL, Landman U. Oxidation of DNA: damage to nucleobases. Acc Chem Res 2010; 43:280-7. [PMID: 19938827 DOI: 10.1021/ar900175a] [Citation(s) in RCA: 255] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
All organisms store the information necessary to maintain life in their DNA. Any process that damages DNA, causing a loss or corruption of that information, jeopardizes the viability of the organism. One-electron oxidation is such a process. In this Account, we address three of the central features of one-electron oxidation of DNA: (i) the migration of the radical cation away from the site of its formation; (ii) the electronic and structural factors that determine the nucleobases at which irreversible reactions most readily occur; (iii) the mechanism of reaction for nucleobase radical cations. The loss of an electron (ionization) from DNA generates an electron "hole" (a radical cation), located most often on its nucleobases, that migrates reversibly through duplex DNA by hopping until it is trapped in an irreversible chemical reaction. The particular sequence of nucleobases in a DNA oligomer determines both the efficiency of hopping and the specific location and nature of the damaging chemical reaction. In aqueous solution, DNA is a polyanion because of the negative charge carried by its phosphate groups. Counterions to the phosphate groups (typically Na(+)) play an important role in facilitating both hopping and the eventual reaction of the radical cation with H(2)O. Irreversible reaction of a radical cation with H(2)O in duplex DNA occurs preferentially at the most reactive site. In normal DNA, comprising the four common DNA nucleobases G, C, A, and T, reaction occurs most commonly at a guanine, resulting in its conversion primarily to 8-oxo-7,8-dihydroguanine (8-OxoG). Both electronic and steric effects control the outcome of this process. If the DNA oligomer does not contain a suitable guanine, then reaction of the radical cation occurs at the thymine of a TT step, primarily by a tandem process. The oxidative damage of DNA is a complex process, influenced by charge transport and reactions that are controlled by a combination of enthalpic, entropic, steric, and compositional factors. These processes occur over a broad distribution of energies, times, and spatial scales. The emergence of a complete picture of DNA oxidation will require additional exploration of the structural, kinetic, and dynamic properties of DNA, but this Account offers insight into key elements of this challenge.
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28
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Joseph J, Schuster GB. One-electron oxidation of DNA: reaction at thymine. Chem Commun (Camb) 2010; 46:7872-8. [DOI: 10.1039/c0cc02118k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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D'Abramo M, Aschi M, Amadei A. Charge transfer equilibria of aqueous single stranded DNA. Phys Chem Chem Phys 2009; 11:10614-8. [PMID: 20145806 DOI: 10.1039/b915312h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The charge transfer thermodynamics of a simple model of DNA, a single stranded 10-mer poly-adenine oligonucleotide, in water is investigated by means of a computational/theoretical procedure, in which all the relevant environmental effects are considered. Our data indicate that water and counterions ultimately dominate the DNA reduction and oxidation free energies, which are also strongly influenced by the base position along the strand. In fact, we estimated that reduction free energies are large and negative, particularly for the bases close to the 5' and 3' positions, whereas the electron detachment is thermodynamically unfavoured all along the strand, but with a higher free energy cost in the central region of the molecule. Further investigation on double charging, i.e. one nucleobase is oxidized and one is reduced within the strand, predicts that charge-separated states are possible and thermodynamically largely stable when the ionic forms are separated by several nucleobases.
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Affiliation(s)
- Marco D'Abramo
- Departament de Bioquímica i Biología Molecular, Facultat de Biología, Universitat de Barcelona, Av. Diagonal 645, Barcelona 08028, Spain.
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30
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Vura-Weis J, Wasielewski MR, Thazhathveetil AK, Lewis FD. Efficient charge transport in DNA diblock oligomers. J Am Chem Soc 2009; 131:9722-7. [PMID: 19558185 DOI: 10.1021/ja9015217] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The realization of highly efficient photoinduced charge separation across the pi-stacked base pairs in duplex DNA remains elusive. The low efficiencies (<5%) typically observed for charge separation over a dozen or more base pairs are a consequence of slow charge transport and rapid charge recombination. We report here a significant (5-fold or greater) enhancement in the efficiency of charge separation in diblock purine oligomers consisting of two or three adenines followed by several guanines, when compared to oligomers consisting of a single purine or alternating base sequences. This approach to wire-like behavior is attributed to both slower charge recombination and faster charge transport once the charge reaches the G-block in these diblock systems.
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Affiliation(s)
- Josh Vura-Weis
- Department of Chemistry and Argonne-Northwestern Solar Energy Research Center, Northwestern University, Evanston, Illinois 60208, USA
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31
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Vladimirov E, Ivanova A, Rösch N. Solvent Reorganization Energies in A-DNA, B-DNA, and Rhodamine 6G−DNA Complexes from Molecular Dynamics Simulations with a Polarizable Force Field. J Phys Chem B 2009; 113:4425-34. [DOI: 10.1021/jp809774q] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Egor Vladimirov
- Theoretische Chemie, Department Chemie, Technische Universität München, 85748 Garching, Germany, and Department of Physical Chemistry, Faculty of Chemistry, University of Sofia, 1 J. Bourchier Ave., 1164 Sofia, Bulgaria
| | - Anela Ivanova
- Theoretische Chemie, Department Chemie, Technische Universität München, 85748 Garching, Germany, and Department of Physical Chemistry, Faculty of Chemistry, University of Sofia, 1 J. Bourchier Ave., 1164 Sofia, Bulgaria
| | - Notker Rösch
- Theoretische Chemie, Department Chemie, Technische Universität München, 85748 Garching, Germany, and Department of Physical Chemistry, Faculty of Chemistry, University of Sofia, 1 J. Bourchier Ave., 1164 Sofia, Bulgaria
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32
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Genereux JC, Augustyn KE, Davis ML, Shao F, Barton JK. Back-electron transfer suppresses the periodic length dependence of DNA-mediated charge transport across adenine tracts. J Am Chem Soc 2008; 130:15150-6. [PMID: 18855390 PMCID: PMC2663386 DOI: 10.1021/ja8052738] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
DNA-mediated charge transport (CT) is exquisitely sensitive to the integrity of the bridging pi-stack and is characterized by a shallow distance dependence. These properties are obscured by poor coupling between the donor/acceptor pair and the DNA bridge, or by convolution with other processes. Previously, we found a surprising periodic length dependence for the rate of DNA-mediated CT across adenine tracts monitored by 2-aminopurine fluorescence. Here we report a similar periodicity by monitoring N 2-cyclopropylguanosine decomposition by rhodium and anthraquinone photooxidants. Furthermore, we find that this periodicity is attenuated by consequent back-electron transfer (BET), as observed by direct comparison between sequences that allow and suppress BET. Thus, the periodicity can be controlled by engineering the extent of BET across the bridge. The periodic length dependence is not consistent with a periodicity predicted by molecular wire theory but is consistent with a model where multiples of four to five base pairs form an ideal CT-active length of a bridging adenine domain.
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Affiliation(s)
- Joseph C. Genereux
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Katherine E. Augustyn
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Molly L. Davis
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Fangwei Shao
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Jacqueline K. Barton
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
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33
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Daublain P, Siegmund K, Hariharan M, Vura-Weis J, Wasielewski MR, Lewis FD, Shafirovich V, Wang Q, Raytchev M, Fiebig T. Photoinduced charge separation in pyrenedicarboxamide-linked DNA hairpins. Photochem Photobiol Sci 2008; 7:1501-8. [DOI: 10.1039/b813995d] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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