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Liu C, Wei X, Zhang H, Zhang M, Yu XF, Hildebrandt N, Luo QY, Jin Z. Nucleic Acid Hybridization Enhanced Luminescence for Rapid and Sensitive RNA and DNA Based Diagnostics. Anal Chem 2022; 94:15964-15970. [DOI: 10.1021/acs.analchem.2c02673] [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]
Affiliation(s)
- Cui Liu
- Department of Biophysics, School of Basic Medical Sciences, Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710049, P. R. China
| | - Xiaoyuan Wei
- Materials Interfaces Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, P. R. China
| | - Huimin Zhang
- The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710061, China
| | - Mingzhen Zhang
- Department of Biophysics, School of Basic Medical Sciences, Xi’an Key Laboratory of Immune Related Diseases, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710049, P. R. China
| | - Xue-Feng Yu
- Materials Interfaces Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, P. R. China
| | - Niko Hildebrandt
- nanoFRET.com, Laboratoire COBRA, Université de Rouen Normandie, CNRS, INSA, 76821 Mont-Saint-Aignan, France
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Qing-Ying Luo
- Materials Interfaces Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, P. R. China
| | - Zongwen Jin
- Materials Interfaces Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, P. R. China
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2
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Hreusová M, Nováková O, Kostrhunová H, Prachařová J, Brabec V, Kašpárková J. DNA modification by cisplatin-like Pt(II) complexes containing 1,1′-binaphtyl-2,2′-diamine ligand does not correlate with their antiproliferative activity in cancer cells. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2019.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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3
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Wu T, Bouř P, Andrushchenko V. Europium (III) as a Circularly Polarized Luminescence Probe of DNA Structure. Sci Rep 2019; 9:1068. [PMID: 30705327 PMCID: PMC6355874 DOI: 10.1038/s41598-018-37680-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 12/12/2018] [Indexed: 01/09/2023] Open
Abstract
We report as a proof-of-concept the first application of circularly polarized luminescence (CPL) measured with a Raman optical activity (ROA) spectrometer to differentiate several DNA structures without need of sensitizing complexes. The ROA/CPL approach provides sufficiently high CPL intensity to use hydrated Eu3+ ions, thus avoiding DNA structural changes associated with binding of sensitizers and overcoming the sensitizer quenching issue. We showed that deoxyguanosine monophosphate (dGMP), single- and double-stranded DNA provide different CPL spectra, which could be used for their discrimination. Our results demonstrate that ROA/CPL method is a promising approach to measure CPL spectra of complex biomolecules when the use of sensitizers is not possible. The method can be extended to other biomolecules, such as proteins, lipids, sugars, etc.
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Affiliation(s)
- Tao Wu
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Petr Bouř
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic
| | - Valery Andrushchenko
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo náměstí 2, 16610, Prague 6, Czech Republic.
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4
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Rehm T, Rothemund M, Bär A, Dietel T, Kempe R, Kostrhunova H, Brabec V, Kasparkova J, Schobert R. N,N-Dialkylbenzimidazol-2-ylidene platinum complexes – effects of alkyl residues and ancillary cis-ligands on anticancer activity. Dalton Trans 2018; 47:17367-17381. [DOI: 10.1039/c8dt03360a] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Benzimidazol-2-ylidene platinum complexes exhibit anticancer activity, which is tuneable via N-alkyl residues and ancillary ligands and is different from that of cisplatin.
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Affiliation(s)
- Tobias Rehm
- Department of Chemistry
- University Bayreuth
- 95440 Bayreuth
- Germany
| | | | - Alexander Bär
- Department of Chemistry
- University Bayreuth
- 95440 Bayreuth
- Germany
| | - Thomas Dietel
- Lehrstuhl fuer Anorganische Chemie II
- University Bayreuth
- 95440 Bayreuth
- Germany
| | - Rhett Kempe
- Lehrstuhl fuer Anorganische Chemie II
- University Bayreuth
- 95440 Bayreuth
- Germany
| | - Hana Kostrhunova
- Institute of Biophysics
- Academy of Sciences of the Czech Republic
- CZ-61265 Brno
- Czech Republic
| | - Viktor Brabec
- Institute of Biophysics
- Academy of Sciences of the Czech Republic
- CZ-61265 Brno
- Czech Republic
| | - Jana Kasparkova
- Institute of Biophysics
- Academy of Sciences of the Czech Republic
- CZ-61265 Brno
- Czech Republic
| | - Rainer Schobert
- Department of Chemistry
- University Bayreuth
- 95440 Bayreuth
- Germany
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5
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Kumamoto Y, Fujita K, Smith NI, Kawata S. Deep-UV biological imaging by lanthanide ion molecular protection. BIOMEDICAL OPTICS EXPRESS 2016; 7:158-70. [PMID: 26819825 PMCID: PMC4722900 DOI: 10.1364/boe.7.000158] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 12/08/2015] [Accepted: 12/11/2015] [Indexed: 05/05/2023]
Abstract
Deep-UV (DUV) light is a sensitive probe for biological molecules such as nucleobases and aromatic amino acids due to specific absorption. However, the use of DUV light for imaging is limited because DUV can destroy or denature target molecules in a sample. Here we show that trivalent ions in the lanthanide group can suppress molecular photodegradation under DUV exposure, enabling a high signal-to-noise ratio and repetitive DUV imaging of nucleobases in cells. Underlying mechanisms of the photodegradation suppression can be excitation relaxation of the DUV-absorptive molecules due to energy transfer to the lanthanide ions, and/or avoiding ionization and reactions with surrounding molecules, including generation of reactive oxygen species, which can modify molecules that are otherwise transparent to DUV light. This approach, directly removing excited energy at the fundamental origin of cellular photodegradation, indicates an important first step towards the practical use of DUV imaging in a variety of biological applications.
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Affiliation(s)
- Yasuaki Kumamoto
- Department of Applied Physics, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Near-field Nanophotonics Research Team, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Currently with the Department of Pathology and Cell Regulation, Kyoto Prefectural University of Medicine, 465 Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Katsumasa Fujita
- Department of Applied Physics, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Nicholas Isaac Smith
- Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Satoshi Kawata
- Department of Applied Physics, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Near-field Nanophotonics Research Team, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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6
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El-Yazbi AF, Loppnow GR. Terbium fluorescence as a sensitive, inexpensive probe for UV-induced damage in nucleic acids. Anal Chim Acta 2013; 786:116-23. [PMID: 23790300 DOI: 10.1016/j.aca.2013.04.068] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 04/23/2013] [Accepted: 04/29/2013] [Indexed: 10/26/2022]
Abstract
Much effort has been focused on developing methods for detecting damaged nucleic acids. However, almost all of the proposed methods consist of multi-step procedures, are limited, require expensive instruments, or suffer from a high level of interferences. In this paper, we present a novel simple, inexpensive, mix-and-read assay that is generally applicable to nucleic acid damage and uses the enhanced luminescence due to energy transfer from nucleic acids to terbium(III) (Tb(3+)). Single-stranded oligonucleotides greatly enhance the Tb(3+) emission, but duplex DNA does not. With the use of a DNA hairpin probe complementary to the oligonucleotide of interest, the Tb(3+)/hairpin probe is applied to detect ultraviolet (UV)-induced DNA damage. The hairpin probe hybridizes only with the undamaged DNA. However, the damaged DNA remains single-stranded and enhances the intrinsic fluorescence of Tb(3+), producing a detectable signal directly proportional to the amount of DNA damage. This allows the Tb(3+)/hairpin probe to be used for sensitive quantification of UV-induced DNA damage. The Tb(3+)/hairpin probe showed superior selectivity to DNA damage compared to conventional molecular beacons probes (MBs) and its sensitivity is more than 2.5 times higher than MBs with a limit of detection of 4.36±1.2 nM. In addition, this probe is easier to synthesize and more than eight times cheaper than MBs, which makes its use recommended for high-throughput, quantitative analysis of DNA damage.
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Affiliation(s)
- Amira F El-Yazbi
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada
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7
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Mlcouskova J, Kasparkova J, Suchankova T, Komeda S, Brabec V. DNA conformation and repair of polymeric natural DNA damaged by antitumor azolato-bridged dinuclear PtII complex. J Inorg Biochem 2012; 114:15-23. [DOI: 10.1016/j.jinorgbio.2012.04.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 04/23/2012] [Accepted: 04/24/2012] [Indexed: 11/17/2022]
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8
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Pracharova J, Zerzankova L, Stepankova J, Novakova O, Farrer NJ, Sadler PJ, Brabec V, Kasparkova J. Interactions of DNA with a new platinum(IV) azide dipyridine complex activated by UVA and visible light: relationship to toxicity in tumor cells. Chem Res Toxicol 2012; 25:1099-111. [PMID: 22420335 DOI: 10.1021/tx300057y] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The Pt(IV) diazido complex trans,trans,trans-[Pt(N(3))(2)(OH)(2)(pyridine)(2)] (1) is unreactive in the dark but is cytotoxic when photoactivated by UVA and visible light. We have shown that 1 when photoactivated accumulates in tumor cells and binds strongly to nuclear DNA under conditions in which it is toxic to tumor cells. The nature of the DNA adducts, including conformational alterations, induced by photoactivated 1 are distinctly different from those produced in DNA by conventional cisplatin or transplatin. In addition, the observation that major DNA adducts of photoactivated 1 are able to efficiently stall RNA polymerase II more efficiently than cisplatin suggests that transcription inhibition may contribute to the cytotoxicity levels observed for photoactivated 1. Hence, DNA adducts of 1 could trigger a number of downstream cellular effects different from those triggered in cancer cells by DNA adducts of cisplatin. This might lead to the therapeutic effects that could radically improve chemotherapy by platinum complexes. The findings of the present work help to explain the different cytotoxic effects of photoactivated 1 and conventional cisplatin and thereby provide new insights into mechanisms associated with the antitumor effects of platinum complexes photoactivated by UVA and visible light.
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Affiliation(s)
- Jitka Pracharova
- Department of Biophysics, Faculty of Science, Palacky University, 17. Listopadu 12, Olomouc, Czech Republic
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9
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Loskotová H, Brabec V. DNA interactions of cisplatin tethered to the DNA minor groove binder distamycin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1999; 266:392-402. [PMID: 10561579 DOI: 10.1046/j.1432-1327.1999.00866.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Modifications of natural DNA in a cell-free medium using cisplatin tethered to the AT-specific, minor groove binder distamycin, were studied using various methods of biochemical analysis or molecular biophysics. These methods include: binding studies using differential pulse polarography and flameless atomic absorption spectrophotometry, mapping DNA adducts using a transcription assay, use of ethidium bromide as a fluorescent probe for DNA adducts of platinum, measurement of DNA unwinding by gel electrophoresis, measurement of CD spectra, an interstrand cross-linking assay using gel electrophoresis under denaturing conditions, measurement of melting curves with the aid of absorption spectrophotometry and the use of terbium ions as a fluorescent probe for distorted base pairs in DNA. The results indicate that attachment of distamycin to cisplatin changes several features of the DNA-binding mode of the parent platinum drug. Major differences comprise different conformational alterations in DNA and a considerably higher efficiency of the conjugated drug to form in DNA interstrand cross-links. Cisplatin tethered to distamycin, however, coordinates to DNA with similar base sequence preferences as the untargeted platinum drug. The results point to a unique profile of DNA binding for cisplatin-distamycin conjugates, suggesting that tethering cisplatin to minor groove oligopeptide binders may also lead to an altered biological activity profile.
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Affiliation(s)
- H Loskotová
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno
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10
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Fu PKL, Turro C. Energy Transfer from Nucleic Acids to Tb(III): Selective Emission Enhancement by Single DNA Mismatches. J Am Chem Soc 1998. [DOI: 10.1021/ja9826082] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Patty K.-L. Fu
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Claudia Turro
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
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11
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Akaboshi M, Tanaka Y, Sumino T, Takada J, Kawai K. Enhanced cell-killing action of cisplatin in the presence of terbium chloride. J Radioanal Nucl Chem 1998. [DOI: 10.1007/bf02386332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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Wheeler V, Jollès B, Miskovsky P, Chinsky L. A resonance Raman spectroscopic study of the quadruplex form of polyriboinosinic acid. J Biomol Struct Dyn 1996; 14:91-9. [PMID: 8877565 DOI: 10.1080/07391102.1996.10508932] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The four stranded form of polyriboinosinic acid, or poly(rl), formed under conditions of high ionic strength, has been studied principally by resonance Raman spectroscopy excited in the ultraviolet absorbent band of the hypoxanthine residues. UV Absorption and circular dichroism studies were made, principally in order to verify the presence of the quadruplex form at the low concentrations of poly(rl) used, and a trial experiment with the structural probe Tb3+ was also performed. Experimental evidence is found for highly stacked metastable forms present at low concentrations of polynucleotide, which are destroyed by heating in favor of the two well known forms.
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13
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Coluccia M, Boccarelli A, Mariggiò MA, Cardellicchio N, Caputo P, Intini FP, Natile G. Platinum(II) complexes containing iminoethers: a trans platinum antitumour agent. Chem Biol Interact 1995; 98:251-66. [PMID: 8548863 DOI: 10.1016/0009-2797(95)03650-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The biological activity of cis and trans complexes of formula [PtCl2(HN = C(OMe)Me)2] has been investigated. The iminoether ligands can have either E or Z configuration about the C = N double bond, therefore EE, EZ and ZZ isomers are obtainable. Substitution of iminoether with EE configuration for amine leads to unexpectedly high antitumor activity for the complex with trans geometry which turns out to be more active than the cis congener in the P388 leukaemia system. The same trans-EE complex shows an activity comparable to that of cisplatin in reducing the primary tumour mass and lung metastases in mice bearing Lewis lung carcinoma, thus representing a trans platinum complex active on both limphoproliferative and solid metastasizing murine tumours. Also the cytotoxicity, the inhibition of DNA synthesis and the mutagenic activity, which are greater for the cis- with respect to the trans-isomer in the amine complexes, are instead greater for the trans- than for the cis- isomer in the case of iminoether compounds. Binding to calf thymus DNA is slower for iminoether complexes than it is for amine complexes, however after 24 h reaction time the level of binding is similar for both types of complexes. Trans-EE, like trans-DDP, does not give the DNA conformational alterations (terbium fluorescence) typical of antitumour-active cis- platinum compounds, but, under strictly analogous experimental conditions, shows a greatly reduced DNA interstrand cross-linking ability (heat denaturation/renaturation assay) with respect to either trans-DDP or cis-EE and cis-DDP. The data in hand point to a new trans platinum antitumour complex with a mechanism of action different from that of cis-DDP and classical analogues.
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Affiliation(s)
- M Coluccia
- Dipartimento di Scienze Biomediche e Oncologia Umana, Sez. Patologia Generale e Oncologia Sperimentale, Policlinico, Bari, Italy
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14
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Justo GZ, Livotto PR, Durán N. Chemical and photochemical generated carbon-centered radical intermediate and its reaction with desoxyribonucleic acid. Free Radic Biol Med 1995; 19:431-40. [PMID: 7590392 DOI: 10.1016/0891-5849(95)00036-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The possible action of carbon-centered radicals in promoting damage to DNA is explored by generation of the 2-phenylethyl radical. The radical is generated during oxidation of phenelzine (2-phenylethyl hydrazine) by ferricyanide, as well as optically from phenylpropionic acid. Covalent binding of the 2-phenylethyl radical to DNA is suggested by studies with the plasmid pBR 322 DNA. Other sensitive techniques used to study DNA damage were the interaction with formaldehyde at 60 degrees C and the fluorescence of DNA-Tb(III) and DNA-DAPI complexes. Theoretical MNDO calculations indicated a preferential attack at position 8 of the guanine residues. This study shows that the 2-phenylethyl radical is able to induce primary effects on nucleic acid structure, leading to alkylated products, especially at purine rings.
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Affiliation(s)
- G Z Justo
- Instituto de Química, Universidade Estadual de Campinas, Brazil
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15
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Jolles B, Laigle A, Liquier J, Chinsky L. Evaluation of the structural modifications induced by mitomycin C on nucleic acids. Biophys Chem 1993; 46:179-85. [PMID: 8513119 DOI: 10.1016/0301-4622(93)85025-d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The interaction of poly(dG-dC).poly(dG-dC) with mitomycin C, an antitumor antibiotic, has been studied by various spectroscopic methods: circular dichroism, Fourier transform infrared resonance Raman scattering and using fluorescence emission of terbium bound to unpaired guanines as local conformation probe. The results allowed us to confirm the lack of long range modification of the DNA secondary structure upon binding. They also brought first information concerning the modification of the local structure of the nucleic acid at the level of mono- or bifunctional adducts.
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Affiliation(s)
- B Jolles
- Laboratoire de Physique et Chimie Biomoléculaires (C.N.R.S. URA 198), Université Pierre et Marie Curie, Paris, France
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16
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Kogan EM, Dyatlova NG, Sidorova NS, Vilner LM, Vrána O, Brabec V. Biophysical studies of the complexes of polyriboguanylic acid with brominated and chlorinated polyribocytidylic acids. Biophys Chem 1991; 40:231-9. [PMID: 1912288 DOI: 10.1016/0301-4622(91)80023-k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Conformation of double-stranded complexes of polyriboguanylic acid with halogenated polyribocytidylic acid [poly(C)] was studied with the aid of differential pulse polarography, terbium fluorescence and circular dichroism spectrometry. It was shown that halogenation at C(5) of cytosine residues in poly(C) disturbed the ordered structure of the double-helical complex. In addition, this halogenation does not improve antiviral activity of the polynucleotide complex studied in the system of vesicular stomatitis virus and the cell culture of chicken embryos. It was concluded that the regularity of the secondary structure of synthetic RNAs might play an important role in the mechanism of biological activity of these biomacromolecules.
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Affiliation(s)
- E M Kogan
- Institute of Macromolecular Compounds, Academy of Sciences of the USSR, Leningrad
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Brabec V, Vrána O, Platonova GA, Kogan EM, Sidorova NS. Biophysical studies of the modification of poly(rG) . poly(rC) by cisplatin. Relations to the biological activity of the complex. Chem Biol Interact 1991; 78:1-12. [PMID: 2009577 DOI: 10.1016/0009-2797(91)90098-r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The integrity of the double-stranded complex polyriboguanylic.polyribocytidylic acid [poly(rG).poly(rC)] modified by antitumour cis-diamminedichloroplatinum(II)(cis-DDP) was studied with the aid of differential pulse polarography and terbium fluorescence measurement. The modification was made to level corresponding to rb = 0.05 (rb is defined as the number of platinum atoms covalently bound per one nucleotide residue). Two modes of the modification of the polynucleotide complex were employed: The action of cis-DDP on poly(G) before formation of the complex with poly(C) and on the complex already formed from non-modified polynucleotides. It was shown that in the latter case modification disordered the integrity of the complex only negligibly. while in the former case the modification resulted in a noticeably more extensive disturbance of the double-stranded polynucleotide complex. Moreover, the modification of the complex (after its formation) at rb = 0.02 led to improved interferon-inducing and antiviral activity of poly(rG).poly(rC) tested on mice infected by influenza virus. It was suggested that the combined effects of interferon-inducing and antiviral activities of poly(rG).poly(rC) and antiviral activity of cis-DDP may result in an increased effect over and above what may be expected from the actions of the two modalities separately.
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Affiliation(s)
- V Brabec
- Institute of Biophysics, Czechoslovak Academy of Sciences, Brno
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18
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Brabec V, Kleinwächter V, Butour JL, Johnson NP. Biophysical studies of the modification of DNA by antitumour platinum coordination complexes. Biophys Chem 1990; 35:129-41. [PMID: 2204440 DOI: 10.1016/0301-4622(90)80003-p] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cisplatin (cis-diamminedichloroplatinum(II] is widely used in the treatment of various human tumours. A large body of experimental evidence indicates that the reaction of cisplatin with DNA is responsible for the cytostatic action of this drug. Several platinum-DNA adducts have been identified and their effect on the conformation of DNA has been investigated. Structural studies of platinum-DNA adducts now permit a reasonably good explanation of the biophysical properties of platinated DNA. Antitumouractive platinum compounds induce in DNA, at low levels of binding, local conformational alterations which have the character of non-denaturing distortions. It is likely that these changes occur in DNA due to the formation of intrastrand cross-links between two adjacent purine residues. On the other hand, the modification of DNA by antitumour-inactive complexes results in the formation of more severe local denaturation changes. Conformational alterations induced in DNA by antitumour-active platinum compounds may be reparable with greater difficulty than those induced by the inactive complexes. Alternatively, non-denaturation change induced in DNA by antitumour platinum drugs could represent more significant steric hindrance against DNA replication as compared with inactive complexes.
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Affiliation(s)
- V Brabec
- Institute of Biophysics, Czechoslovak Academy of Sciences, Brno
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