1
|
Rademacher MP, Rohn T, Haselbach W, Ott AT, Bringmann PW, Gilch P. Spectroscopic view on the interaction between the psoralen derivative amotosalen and DNA. Photochem Photobiol Sci 2024; 23:693-709. [PMID: 38457118 DOI: 10.1007/s43630-024-00545-2] [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: 12/15/2023] [Accepted: 02/01/2024] [Indexed: 03/09/2024]
Abstract
Psoralens are eponymous for PUVA (psoralen plus UV-A radiation) therapy, which inter alia can be used to treat various skin diseases. Based on the same underlying mechanism of action, the synthetic psoralen amotosalen (AMO) is utilized in the pathogen reduction technology of the INTERCEPT® Blood System to inactivate pathogens in plasma and platelet components. The photophysical behavior of AMO in the absence of DNA is remarkably similar to that of the recently studied psoralen 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT). By means of steady-state and time-resolved spectroscopy, intercalation and photochemistry of AMO and synthetic DNA were studied. AMO intercalates with a higher affinity into A,T-only DNA (KD = 8.9 × 10-5 M) than into G,C-only DNA (KD = 6.9 × 10-4 M). AMO covalently photobinds to A,T-only DNA with a reaction quantum yield of ΦR = 0.11. Like AMT, it does not photoreact following intercalation into G,C-only DNA. Femto- and nanosecond transient absorption spectroscopy reveals the characteristic pattern of photobinding to A,T-only DNA. For AMO and G,C-only DNA, signatures of a photoinduced electron transfer are recorded.
Collapse
Affiliation(s)
- Michelle P Rademacher
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - Tim Rohn
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - Wiebke Haselbach
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - A Theresa Ott
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | | | - Peter Gilch
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany.
| |
Collapse
|
2
|
Ivanov AA, Ukladov EA, Kremis SA, Sharapov SZ, Baiborodin SI, Lipeeva AV, Shults EE, Golubeva TS. Investigation of cytotoxic and antioxidative activity of 1,2,3-triazolyl-modified furocoumarins and 2,3-dihydrofurocoumarins. PROTOPLASMA 2022; 259:1321-1330. [PMID: 35080665 DOI: 10.1007/s00709-022-01739-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
High biological activity of natural furocoumarins is often linked to a series of adverse side effects, e.g., genotoxicity. This makes it desirable to develop semi-synthetic derivatives with reduced negative activity while retaining or even enhancing the positive properties. Previously, we have studied the genotoxic activity of a library of twenty-one 1,2,3-triazolyl-modified furocoumarins and 2,3-dihydrofurocoumarins and identified modifications that minimize the negative properties. In the current article, we report on an investigation into the cytotoxic activity of the same library. We have aimed to rank the substances in order of the severity of their cytotoxicity and therefore to predict, with the use of statistical processing, the most promising substituents for the furocoumarin scaffold.
Collapse
Affiliation(s)
- Artemii A Ivanov
- Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | | | - Stepan A Kremis
- Federal Research Center of Fundamental and Translational Medicine SB RAS, Novosibirsk, Russia
| | - Sodbo Z Sharapov
- Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia
- Novosibirsk State University, Novosibirsk, Russia
| | | | - Alla V Lipeeva
- Novosibirsk Institute of Organic Chemistry SB RAS, Novosibirsk, Russia
| | - Elvira E Shults
- Novosibirsk Institute of Organic Chemistry SB RAS, Novosibirsk, Russia
| | - Tatiana S Golubeva
- Institute of Cytology and Genetics SB RAS, Novosibirsk, Russia.
- Novosibirsk State University, Novosibirsk, Russia.
| |
Collapse
|
3
|
Bertling J, Thom KA, Geenen S, Jeuken H, Presser L, Müller TJJ, Gilch P. Synthesis and Photophysics of Water-Soluble Psoralens with Red-Shifted Absorption. Photochem Photobiol 2021; 97:1534-1547. [PMID: 34181757 DOI: 10.1111/php.13480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/24/2021] [Indexed: 11/26/2022]
Abstract
8-Methoxypsoralen (8-MOP) serves as a PUVA (psoralen + UV-A) agent in the treatment of certain skin diseases. Derivatives of 8-MOP with cationic aromatic substituents at the five positions were synthesized and characterized by steady-state, femtosecond and nanosecond spectroscopy as well as cyclic voltammetry. The aromatic substituents' positive charge increases the water solubility and the affinity toward intercalation into DNA. The aromatic substituents were supposed to lower the psoralen S1 energy and thereby suppress a photo-induced electron transfer (PET) with guanine-bearing DNA. Such a suppression of this PET is expected to increase the propensity of psoralens to photo-addition to DNA. For derivatives bearing methylpyridinium residues, femtosecond spectroscopy revealed an intramolecular PET occurring on the picosecond time scale. This PET precludes the population of the triplet state. As triplet states are the precursor state for the photo-addition to DNA, their intermolecular PET renders these derivatives ineffective in terms of PUVA. For two derivatives bearing trimethylphenylammonium moieties, such an intramolecular PET does not occur and the triplet state is populated. Surprisingly, these compounds also exhibit no PUVA activity. Based on these findings, implications for further optimization of PUVA agents are discussed.
Collapse
Affiliation(s)
- Janina Bertling
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Kristoffer A Thom
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Sarah Geenen
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Hannah Jeuken
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Lysander Presser
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Thomas J J Müller
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Peter Gilch
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| |
Collapse
|
4
|
Baptista MS, Cadet J, Greer A, Thomas AH. Photosensitization Reactions of Biomolecules: Definition, Targets and Mechanisms. Photochem Photobiol 2021; 97:1456-1483. [PMID: 34133762 DOI: 10.1111/php.13470] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 06/13/2021] [Indexed: 02/07/2023]
Abstract
Photosensitization reactions have been demonstrated to be largely responsible for the deleterious biological effects of UV and visible radiation, as well as for the curative actions of photomedicine. A large number of endogenous and exogenous photosensitizers, biological targets and mechanisms have been reported in the past few decades. Evolving from the original definitions of the type I and type II photosensitized oxidations, we now provide physicochemical frameworks, classifications and key examples of these mechanisms in order to organize, interpret and understand the vast information available in the literature and the new reports, which are in vigorous growth. This review surveys in an extended manner all identified photosensitization mechanisms of the major biomolecule groups such as nucleic acids, proteins, lipids bridging the gap with the subsequent biological processes. Also described are the effects of photosensitization in cells in which UVA and UVB irradiation triggers enzyme activation with the subsequent delayed generation of superoxide anion radical and nitric oxide. Definitions of photosensitized reactions are identified in biomolecules with key insights into cells and tissues.
Collapse
Affiliation(s)
| | - Jean Cadet
- Département de Médecine Nucléaire et de Radiobiologie, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Alexander Greer
- Department of Chemistry, Brooklyn College, Brooklyn, NY, USA.,Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, NY, USA
| | - Andrés H Thomas
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), CCT La Plata-CONICET, La Plata, Argentina
| |
Collapse
|
5
|
Wang LL, Wang HH, Wang H, Liu HY. Photoinduced Electron Transfer between DNA and Water-Soluble Porphyrins. J Phys Chem B 2021; 125:5683-5693. [PMID: 34042460 DOI: 10.1021/acs.jpcb.0c09335] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photophysical properties of five kinds of porphyrins (H2TMPyP, ZnTMPyP, PdTMPyP, H2TPPS, and ZnTPPS) complexed with model DNAs (ctDNA and dGMP) have been investigated using steady-state absorption, circular dichroism (CD), and femtosecond transient absorption spectroscopy. Upon addition of ctDNA (or dGMP), larger hypochromism and red shifts are observed for H2TMPyP and PdTMPyP compared to the other samples. The steady-state measurements have suggested that the binding modes of H2TMPyP-ctDNA and PdTMPyP-ctDNA are partial intercalation and full intercalation, respectively, while ZnTMPyP-ctDNA shows outside groove binding. No significant interaction was observed between both H2TPPS and ZnTPPS with two kinds of DNA. Upon excitation of the porphyrins into the higher excited state S2 (Soret band), the appearance of the transient absorption from ∼500 to ∼620 nm at about 0.05 ps in H2TMPyP-ctDNA, H2TMPyP-dGMP, and PdTMPyP-dGMP indicates the occurrence of the electron transfer (ET) from guanine to H2TMPyP and PdTMPyP. The forward ET are extremely fast (kf ≥ 1.0 × 1013 s-1), and the backward ET rates are ∼5.6 × 1012 and ∼4.0 × 1012 s-1, respectively. The complexation with DNA may lead to the shorter lifetime of the fluorescence of H2TMPyP and PdTMPyP.
Collapse
Affiliation(s)
- Li-Li Wang
- State Key Laboratory of Optoelectronics Materials and Technologies, Sun Yat-Sen University, Guangzhou 510275, China
| | - Hua-Hua Wang
- Department of Chemistry, South China University of Technology, Guangzhou 510641, China
| | - Hui Wang
- State Key Laboratory of Optoelectronics Materials and Technologies, Sun Yat-Sen University, Guangzhou 510275, China
| | - Hai-Yang Liu
- Department of Chemistry, South China University of Technology, Guangzhou 510641, China
| |
Collapse
|
6
|
Lu C, Gutierrez-Bayona NE, Taylor JS. The effect of flanking bases on direct and triplet sensitized cyclobutane pyrimidine dimer formation in DNA depends on the dipyrimidine, wavelength and the photosensitizer. Nucleic Acids Res 2021; 49:4266-4280. [PMID: 33849058 PMCID: PMC8096240 DOI: 10.1093/nar/gkab214] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 03/15/2021] [Accepted: 04/08/2021] [Indexed: 12/11/2022] Open
Abstract
Cyclobutane pyrimidine dimers (CPDs) are the major products of DNA produced by direct absorption of UV light, and result in C to T mutations linked to human skin cancers. Most recently a new pathway to CPDs in melanocytes has been discovered that has been proposed to arise from a chemisensitized pathway involving a triplet sensitizer that increases mutagenesis by increasing the percentage of C-containing CPDs. To investigate how triplet sensitization may differ from direct UV irradiation, CPD formation was quantified in a 129-mer DNA designed to contain all 64 possible NYYN sequences. CPD formation with UVB light varied about 2-fold between dipyrimidines and 12-fold with flanking sequence and was most frequent at YYYR and least frequent for GYYN sites in accord with a charge transfer quenching mechanism. In contrast, photosensitized CPD formation greatly favored TT over C-containing sites, more so for norfloxacin (NFX) than acetone, in accord with their differing triplet energies. While the sequence dependence for photosensitized TT CPD formation was similar to UVB light, there were significant differences, especially between NFX and acetone that could be largely explained by the ability of NFX to intercalate into DNA.
Collapse
Affiliation(s)
- Chen Lu
- Department of Chemistry, Washington University, One Brookings Dr., St. Louis, MO 63130, USA
| | | | - John-Stephen Taylor
- Department of Chemistry, Washington University, One Brookings Dr., St. Louis, MO 63130, USA
| |
Collapse
|
7
|
Diekmann J, Theves I, Thom KA, Gilch P. Tracing the Photoaddition of Pharmaceutical Psoralens to DNA. Molecules 2020; 25:E5242. [PMID: 33182821 PMCID: PMC7696755 DOI: 10.3390/molecules25225242] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/06/2020] [Accepted: 11/07/2020] [Indexed: 01/14/2023] Open
Abstract
The psoralens 8-methoxypsoralen (8-MOP), 4,5',8-trimethylpsoralen (TMP) and 5-methoxypsoralen (5-MOP) find clinical application in PUVA (psoralen + UVA) therapy. PUVA treats skin diseases like psoriasis and atopic eczema. Psoralens target the DNA of cells. Upon photo-excitation psoralens bind to the DNA base thymine. This photo-binding was studied using steady-state UV/Vis and IR spectroscopy as well as nanosecond transient UV/Vis absorption. The experiments show that the photo-addition of 8-MOP and TMP involve the psoralen triplet state and a biradical intermediate. 5-MOP forms a structurally different photo-product. Its formation could not be traced by the present spectroscopic technique.
Collapse
Affiliation(s)
| | | | | | - Peter Gilch
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany; (J.D.); (I.T.); (K.A.T.)
| |
Collapse
|
8
|
Geenen SR, Schumann T, Müller TJJ. Fluorescent Donor-Acceptor Psoralen Cruciforms by Consecutive Suzuki-Suzuki and Sonogashira-Sonogashira One-Pot Syntheses. J Org Chem 2020; 85:9737-9750. [PMID: 32575986 DOI: 10.1021/acs.joc.0c01059] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Two novel donor-acceptor cruciform topologies are efficiently synthesized by site-selective Suzuki-Suzuki and Sonogashira-Sonogashira multicomponent reactions starting from a bromo-triflato-functionalized psoralen scaffold. In addition to tunability of photophysical properties, such as absorption and emission, many derivatives possess partially high relative fluorescence quantum yields in solution and fluoresce strongly in the solid state. Additionally, the promising compounds show solvatochromism and acidochromic effects. In addition, 8-p-anisyl-5-p-cyanophenyl-substituted psoralen exhibits aggregation-induced emission properties. Experimentally (applying the Lippert-Mataga model) and computationally (TD-DFT calculations), the pronounced charge transfer character of the longest wavelength absorption band was confirmed.
Collapse
Affiliation(s)
- Sarah R Geenen
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | - Torben Schumann
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | - Thomas J J Müller
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| |
Collapse
|
9
|
Buhimschi AD, Gooden DM, Jing H, Fels DR, Hansen KS, Beyer WF, Dewhirst MW, Walder H, Gasparro FP. Psoralen Derivatives with Enhanced Potency. Photochem Photobiol 2020; 96:1014-1031. [PMID: 32221980 DOI: 10.1111/php.13263] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Accepted: 02/28/2020] [Indexed: 12/22/2022]
Abstract
Psoralen is a furocoumarin natural product that intercalates within DNA and forms covalent adducts when activated by ultraviolet radiation. It is well known that this property contributes to psoralen's clinical efficacy in several disease contexts, which include vitiligo, psoriasis, graft-versus-host disease and cutaneous T-cell lymphoma. Given the therapeutic relevance of psoralen and its derivatives, we attempted to synthesize psoralens with even greater potency. In this study, we report a library of 73 novel psoralens, the largest collection of its kind. When screened for the ability to reduce cell proliferation, we identified two derivatives even more cytotoxic than 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT), one of the most potent psoralens identified to date. Using MALDI-TOF MS, we studied the DNA adduct formation for a subset of novel psoralens and found that in most cases enhanced DNA binding correlated well with cytotoxicity. Generally, our most potent derivatives contain positively charged substituents, which we believe increase DNA affinity and enhance psoralen intercalation. Thus, we provide a rational approach to guide efforts toward further optimizing psoralens to fully capitalize on this drug class' therapeutic potential. Finally, the structure-activity insights we have gained shed light on several opportunities to study currently underappreciated aspects of psoralen's mechanism.
Collapse
Affiliation(s)
- Alexandru D Buhimschi
- Medical Scientist Training Program, Northwestern University Feinberg School of Medicine, Chicago, IL.,Photobiology Laboratory, Hamden Hall Country Day School, Hamden, CT
| | | | - Hongwu Jing
- Department of Obstetrics and Gynecology, University of Illinois College of Medicine, Chicago, IL
| | - Diane R Fels
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC.,Duke Cancer Institute, Duke University Medical Center, Durham, NC
| | - Katherine S Hansen
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC.,Duke Cancer Institute, Duke University Medical Center, Durham, NC
| | | | - Mark W Dewhirst
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC.,Duke Cancer Institute, Duke University Medical Center, Durham, NC
| | | | | |
Collapse
|
10
|
Geenen SR, Presser L, Hölzel T, Ganter C, Müller TJJ. Electronic Finetuning of 8-Methoxy Psoralens by Palladium-Catalyzed Coupling: Acidochromicity and Solvatochromicity. Chemistry 2020; 26:8064-8075. [PMID: 32048795 PMCID: PMC7383860 DOI: 10.1002/chem.201905676] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Indexed: 12/21/2022]
Abstract
Differently 5‐substituted 8‐methoxypsoralens can be synthesized by an efficient synthetic route with various cross‐coupling methodologies, such as Suzuki, Sonogashira and Heck reaction. Compared to previously synthesized psoralens, thereby promising daylight absorbing compounds as potentially active agents against certain skin diseases can be readily accessed. Extensive investigations of all synthesized psoralen derivatives reveal fluorescence in the solid state as well as several distinctly emissive derivatives in solution. Donor‐substituted psoralens exhibit remarkable photophysical properties, such as high fluorescence quantum yields and pronounced emission solvatochromicity and acidochromicity, which were scrutinized by Lippert–Mataga and Stern–Volmer plots. The results indicate that the compounds exceed the limit of visible light, a significant factor for potential applications as an active agent. In addition, (TD)DFT calculations were performed to elucidate the underlying electronic structure and to assign experimentally obtained data.
Collapse
Affiliation(s)
- Sarah R Geenen
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Lysander Presser
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Torsten Hölzel
- Institut für Anorganische Chemie und Strukturchemie I, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Christian Ganter
- Institut für Anorganische Chemie und Strukturchemie I, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Thomas J J Müller
- Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| |
Collapse
|
11
|
Diekmann J, Gontcharov J, Fröbel S, Torres Ziegenbein C, Zinth W, Gilch P. The Photoaddition of a Psoralen to DNA Proceeds via the Triplet State. J Am Chem Soc 2019; 141:13643-13653. [DOI: 10.1021/jacs.9b06521] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Janina Diekmann
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Julia Gontcharov
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik and Center for Integrated Protein Science Munich CIPSM, Ludwig-Maximilians-Universität München, Oettingenstrasse 67, 80538 München, Germany
| | - Sascha Fröbel
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Christian Torres Ziegenbein
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Wolfgang Zinth
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik and Center for Integrated Protein Science Munich CIPSM, Ludwig-Maximilians-Universität München, Oettingenstrasse 67, 80538 München, Germany
| | - Peter Gilch
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| |
Collapse
|
12
|
Paul S, Samanta A. Ground- and Excited-State Interactions of a Psoralen Derivative with Human Telomeric G-Quadruplex DNA. J Phys Chem B 2018; 122:2277-2286. [PMID: 29376354 DOI: 10.1021/acs.jpcb.7b12475] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
G-quadruplex DNA has been a recent target for anticancer agents, and its binding interactions with small molecules, often used as anticancer drugs, have become an important area of research. Considering that psoralens have long been studied in the context of duplex DNA but that very little is known about their potential as G-quadruplex binders and their excited-state interaction with the latter has not been explored, we have studied herein the binding of a planar water-soluble psoralen derivative, 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT), with the 22-mer human telomeric G-quadruplex-forming sequence, AGGG(TTAGGG)3, labeled here as (hTel22), and investigated the consequences of photoexcitation of AMT by calorimetric and spectroscopic techniques. The results show an enthalpy-driven 1:1 binding of AMT with hTel22 via end-stacking mode. Fluorescence quenching experiments on 6-fluorescein amidite-labeled oligomers indicate that the binding site is nearer to the 3' end of hTel22 in the diagonal loop region. Femtosecond time-resolved transient absorption measurements indicate electron transfer from the guanine moiety of hTel22 to photoexcited AMT, leading to the formation of a radical pair species (AMT•-G•+), which survives for 30 ps and is favored by a parallel/quasi-parallel orientation between the two. The findings reveal psoralens as a prospective class of compounds for the development of anticancer therapeutics by targeting the G-quadruplex DNA.
Collapse
Affiliation(s)
- Sneha Paul
- School of Chemistry, University of Hyderabad , Hyderabad 500046, India
| | - Anunay Samanta
- School of Chemistry, University of Hyderabad , Hyderabad 500046, India
| |
Collapse
|
13
|
Jie J, Liu K, Wu L, Zhao H, Song D, Su H. Capturing the radical ion-pair intermediate in DNA guanine oxidation. SCIENCE ADVANCES 2017; 3:e1700171. [PMID: 28630924 PMCID: PMC5457143 DOI: 10.1126/sciadv.1700171] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 04/06/2017] [Indexed: 05/28/2023]
Abstract
Although the radical ion pair has been frequently invoked as a key intermediate in DNA oxidative damage reactions and photoinduced electron transfer processes, the unambiguous detection and characterization of this species remain formidable and unresolved due to its extremely unstable nature and low concentration. We use the strategy that, at cryogenic temperatures, the transient species could be sufficiently stabilized to be detectable spectroscopically. By coupling the two techniques (the cryogenic stabilization and the time-resolved laser flash photolysis spectroscopy) together, we are able to capture the ion-pair transient G+•⋯Cl- in the chlorine radical-initiated DNA guanine (G) oxidation reaction, and provide direct evidence to ascertain the intricate type of addition/charge separation mechanism underlying guanine oxidation. The unique spectral signature of the radical ion-pair G+•⋯Cl- is identified, revealing a markedly intense absorption feature peaking at 570 nm that is distinctive from G+• alone. Moreover, the ion-pair spectrum is found to be highly sensitive to the protonation equilibria within guanine-cytosine base pair (G:C), which splits into two resolved bands at 480 and 610 nm as the acidic proton transfers along the central hydrogen bond from G+• to C. We thus use this exquisite sensitivity to track the intrabase-pair proton transfer dynamics in the double-stranded DNA oligonucleotides, which is of critical importance for the description of the proton-coupled charge transfer mechanisms in DNA.
Collapse
Affiliation(s)
- Jialong Jie
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kunhui Liu
- College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Lidan Wu
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Hongmei Zhao
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Di Song
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Hongmei Su
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- College of Chemistry, Beijing Normal University, Beijing 100875, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|