1
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Heidari A, Dehghanian E, Razmara Z, Shahraki S, Samareh Delarami H, Heidari Majd M. Effect of Cu(II) compound containing dipicolinic acid on DNA damage: a study of antiproliferative activity and DNA interaction properties by spectroscopic, molecular docking and molecular dynamics approaches. J Biomol Struct Dyn 2024:1-16. [PMID: 38498382 DOI: 10.1080/07391102.2024.2329308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 03/06/2024] [Indexed: 03/20/2024]
Abstract
A polymeric compound formulized as [Cu(µ-dipic)2{Na2(µ-H2O)4]n.2nH2O (I), where dipic is 2,6-pyridine dicarboxylic acid (dipicolinic acid, H2dipic), was synthesized by sonochemical irradiation. The initial in-vitro cytotoxic activity of this complex compared with renowned anticancer drugs like cisplatin, versus HCT116 colon cell lines, shows promising results. This study investigated the interaction mode between compound (I) and calf-thymus DNA utilizing a range of analytical techniques including spectrophotometry, fluorimetry, partition coefficient analysis, viscometry, gel electrophoresis and molecular docking technique. The results obtained from experimental methods reveal complex (I) could bind to CT-DNA via hydrogen bonding and van der Waals forces and the theoretical methods support it. Also, complex (I) indicates nuclease activity in the attendance of H2O2 and can act as an artificial nuclease to cleave DNA with high efficiency.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Ameneh Heidari
- Department of Chemistry, Faculty of Science, University of Zabol, Zabol, Iran
| | - Effat Dehghanian
- Department of Chemistry, University of Sistan and Baluchestan, Zahedan, Iran
| | - Zohreh Razmara
- Department of Chemistry, Faculty of Science, University of Zabol, Zabol, Iran
| | - Somaye Shahraki
- Department of Chemistry, Faculty of Science, University of Zabol, Zabol, Iran
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2
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Heidari A, Mansouri-Torshizi H, Saeidifar M, Dehghanian E, Abdi K, Delarami HS. Diverse coordination of dipicolinic acid to Pd(II) ion result antitumor complexes, their interaction with CT-DNA by spectroscopic experiments and computational methods. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.132937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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3
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Andrade UMS, Castro ASB, Oliveira PHF, da Silva LHM, Rocha MS. Imidazolium-based ionic liquids binding to DNA: Mechanical effects and thermodynamics of the interactions. Int J Biol Macromol 2022; 214:500-511. [PMID: 35714872 DOI: 10.1016/j.ijbiomac.2022.06.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/09/2022] [Accepted: 06/10/2022] [Indexed: 11/30/2022]
Abstract
We performed a robust characterization of the molecular interactions between the DNA molecule and two imidazolium-based ionic liquids (ILs): 1-Butyl-3-methylimidazolium chloride ([bmim]Cl) and 1-Octyl-3-methylimidazolium chloride ([omim]Cl), using single molecule approaches (optical and magnetic tweezers) and bulk techniques (isothermal titration calorimetry and conductivity measurements). Optical and magnetic tweezers allowed us to obtain the changes on the mechanical properties of the DNA complexes formed with both ILs, as well as the relevant physicochemical (binding) parameters of the interaction. Despite the weak binding measured between DNA and the two ILs, we identify a transition on the regime of polymer elasticity of the complexes formed, which results in a relevant DNA compaction for high IL concentrations. In addition, isothermal titration calorimetry and conductivity complemented the single molecule investigation, giving a complete thermodynamic characterization of the interactions and allowing the identification of the most relevant driving forces at various different concentration ranges of the ILs. Based on the results obtained with all the employed techniques, we propose a model for the binding schemes involving DNA and both [bmim]Cl and [omim]Cl.
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Affiliation(s)
- U M S Andrade
- Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil; Departamento de Formação Geral, Centro Federal de Educação Tecnológica de Minas Gerais, Curvelo, Minas Gerais, Brazil.
| | - A S B Castro
- Departamento de Química, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - P H F Oliveira
- Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - L H M da Silva
- Departamento de Química, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - M S Rocha
- Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
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4
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de Oliveira RM, Moura TA, Rocha MS. Caffeine Enhances the Toxicity of Platinum-Based Drugs at the Molecular Level Even Outside of the Intracellular Environment: A Single-Molecule Force Spectroscopy Study. J Phys Chem B 2022; 126:3291-3299. [PMID: 35442688 DOI: 10.1021/acs.jpcb.2c01553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
It is well reported in the literature that caffeine, the most consumed alkaloid around the world, enhances the anticancer effects of the drug cisplatin by inhibiting DNA repair by the cellular machinery. Here, we perform single-molecule force spectroscopy assays with optical tweezers to show that caffeine enhances the toxicity not only of cisplatin but also of various different platinum-based drugs already at the molecular level, using samples containing only double-stranded (ds)DNA, platinum drugs, and the alkaloid in a simple phosphate buffer, that is, completely out of the complex environment found inside real living cells. In fact, our results show that caffeine acts as an allosteric catalyst which increases the effective equilibrium binding constant between DNA and the platinum drugs, also interfering in the cooperativity of the binding reactions. To the best of our knowledge, this is the first time that such a property of caffeine was demonstrated and characterized from a pure physicochemical perspective, outside the cellular environment. Thus, the present work provides new insights into the use of this alkaloid for current chemotherapeutic applications.
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Affiliation(s)
- Rayane M de Oliveira
- Departamento de Física, Universidade Federal de Viçosa, Viçosa 36570-900, Minas Gerais, Brazil
| | - Tiago A Moura
- Departamento de Física, Universidade Federal de Viçosa, Viçosa 36570-900, Minas Gerais, Brazil
| | - Márcio S Rocha
- Departamento de Física, Universidade Federal de Viçosa, Viçosa 36570-900, Minas Gerais, Brazil
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Villaluenga JP, Cao-García FJ. Cooperative kinetics of ligand binding to linear polymers. Comput Struct Biotechnol J 2022; 20:521-533. [PMID: 35495112 PMCID: PMC9019704 DOI: 10.1016/j.csbj.2021.12.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/27/2021] [Accepted: 12/30/2021] [Indexed: 11/29/2022] Open
Abstract
Cooperative kinetic equation for large ligands binding to long polymers. Cooperativity in general affects binding and release rates. Appropriate counting of the available binding sites for a ligand to a linear polymer. Positive cooperativity increases polymer coverage by the ligand. Large ligand size reduces cooperativity effects.
Ligands change the chemical and mechanical properties of polymers. In particular, single strand binding protein (SSB) non-specifically bounds to single-stranded DNA (ssDNA), modifying the ssDNA stiffness and the DNA replication rate, as recently measured with single-molecule techniques. SSB is a large ligand presenting cooperativity in some of its binding modes. We aim to develop an accurate kinetic model for the cooperative binding kinetics of large ligands. Cooperativity accounts for the changes in the affinity of a ligand to the polymer due to the presence of another bound ligand. Large ligands, attaching to several binding sites, require a detailed counting of the available binding possibilities. This counting has been done by McGhee and von Hippel to obtain the equilibrium state of the ligands-polymer complex. The same procedure allows to obtain the kinetic equations for the cooperative binding of ligands to long polymers, for all ligand sizes. Here, we also derive approximate cooperative kinetic equations in the large ligand limit, at the leading and next-to-leading orders. We found cooperativity is negligible at the leading-order, and appears at the next-to-leading order. Positive cooperativity (increased affinity) can be originated by increased binding affinity or by decreased release affinity, implying different kinetics. Nevertheless, the equilibrium state is independent of the origin of cooperativity and only depends on the overall increase in affinity. Next-to-leading approximation is found to be accurate, particularly for small cooperativity. These results allow to understand and characterize relevant ligand binding processes, as the binding kinetics of SSB to ssDNA, which has been reported to affect the DNA replication rate for several SSB-polymerase pairs.
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Affiliation(s)
- Juan P.G. Villaluenga
- Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid, Plaza de Ciencias, 1, 28040 Madrid, Spain
- Corresponding author.
| | - Francisco Javier Cao-García
- Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid, Plaza de Ciencias, 1, 28040 Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia, IMDEA Nanociencia, Calle Faraday, 9, 28049 Madrid, Spain
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6
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Bazoni RF, Moura TA, Rocha MS. Hydroxychloroquine Exhibits a Strong Complex Interaction with DNA: Unraveling the Mechanism of Action. J Phys Chem Lett 2020; 11:9528-9534. [PMID: 33115235 DOI: 10.1021/acs.jpclett.0c02590] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In the past months, the use of the drug hydroxychloroquine has considerably increased in many countries, associated with a proposed treatment for the COVID-19 disease. Although there is no conclusive evidence about the efficacy of the drug for this purpose, surprisingly there are no conclusive studies in the literature concerning its mechanism of action inside cells, which is related to its interaction with nucleic acids. Here, we performed a robust characterization of the interaction between hydroxychloroquine and double-stranded DNA using single-molecule force spectroscopy and gel electrophoresis. Two different binding modes were identified, namely, minor groove binding for low drug concentrations and intercalation for high drug concentrations, and the sets of binding parameters were determined for each of these modes. Such results have unraveled in detail the molecular mechanism of action of the drug as a DNA ligand.
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Affiliation(s)
- R F Bazoni
- Departamento de Ciências Naturais, Universidade Federal do Espírito Santo, São Mateus, Espírito Santo 29.932-540, Brazil
| | - T A Moura
- Departamento de Física, Universidade Federal de Viçosa. Viçosa, Minas Gerais 36.570-900, Brazil
| | - M S Rocha
- Departamento de Física, Universidade Federal de Viçosa. Viçosa, Minas Gerais 36.570-900, Brazil
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7
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Silva EF, Andrade UMS, de Oliveira KM, Teixeira AVNC, Rocha MS. Dodecyltrimethylammonium bromide surfactant effects on DNA: Unraveling the competition between electrostatic and hydrophobic interactions. Phys Rev E 2020; 102:032401. [PMID: 33076016 DOI: 10.1103/physreve.102.032401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 08/16/2020] [Indexed: 01/04/2023]
Abstract
We present a new study on the interaction of the DNA molecule with the surfactant dodecyltrimethylammonium bromide (DTAB), performed mainly with optical tweezers. Single-molecule force spectroscopy experiments performed in the low-force entropic regime allowed a robust characterization of the DNA-DTAB interaction, unveiling how the surfactant changes the mechanical properties of the biopolymer, the binding parameters, and the competition of the two mechanisms involved in the interaction: electrostatic attraction between the cationic surfactant heads and the negative phosphate backbone of the DNA and hydrophobic interactions between the tails of the bound DTAB molecules, which can result in DNA compaction in solution depending on the quantity of bound surfactant. Finally, force clamp experiments with magnetic tweezers and gel electrophoresis assays confirm that DTAB compacts DNA depending not only on the surfactant concentration but also on the conformation of the biopolymer in solution. The present study provides new insights on general aspects of the DNA-surfactant complexes formation, contributing to the fundamental knowledge of the physics of such interactions.
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Affiliation(s)
- E F Silva
- Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil and Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, Minas Gerais, 36036-900, Brazil
| | - U M S Andrade
- Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil and Departamento de Formação Geral, Centro Federal de Educação Tecnológica de Minas Gerais, Curvelo, Minas Gerais, 35790-000, Brasil
| | - K M de Oliveira
- Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - A V N C Teixeira
- Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - M S Rocha
- Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
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8
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On the use of Europium (Eu) for designing new metal-based anticancer drugs. Biochem Biophys Res Commun 2020; 531:372-376. [DOI: 10.1016/j.bbrc.2020.07.080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 07/17/2020] [Indexed: 11/18/2022]
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9
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Oliveira L, Caquito JM, Rocha MS. Transplatin ineffectiveness against cancer from a molecular perspective: A single-molecule force-spectroscopy study. Phys Rev E 2020; 101:062412. [PMID: 32688610 DOI: 10.1103/physreve.101.062412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 05/25/2020] [Indexed: 11/07/2022]
Abstract
By performing single-molecule force spectroscopy with optical tweezers, we have characterized the interaction between the platinum-based compound transplatin and the DNA molecule, establishing a critical comparison with its isomer cisplatin. While transplatin is ineffective against tumor cells, its isomer is one of the most used drugs in current chemotherapies, and a molecular study on this difference performed at the single-molecule level was lacking until the present work. Our experiments show that transplatin binds DNA under low chloride concentrations (a situation usually found inside many cells) with an equilibrium association binding constant about four orders of magnitude lower than cisplatin. In addition, we have found that, at saturation, transplatin binds preferentially forming interstrand cross links and monoadducts, a situation very different from cisplatin, which forms preferentially intrastrand cross links. Such differences explain the ineffectiveness of transplatin in killing tumor cells. From a physical point of view, the present study advances in using the mechanical properties of the DNA molecule as sensors to evaluate the therapeutic efficiency of drugs.
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Affiliation(s)
- L Oliveira
- Departamento de Física, Universidade Federal de Viçosa. Viçosa, Minas Gerais, Brazil
| | - J M Caquito
- Departamento de Física, Universidade Federal de Viçosa. Viçosa, Minas Gerais, Brazil
| | - M S Rocha
- Departamento de Física, Universidade Federal de Viçosa. Viçosa, Minas Gerais, Brazil
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10
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Villaluenga JPG, Vidal J, Cao-García FJ. Noncooperative thermodynamics and kinetic models of ligand binding to polymers: Connecting McGhee-von Hippel model with the Tonks gas model. Phys Rev E 2020; 102:012407. [PMID: 32795076 DOI: 10.1103/physreve.102.012407] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 06/18/2020] [Indexed: 11/07/2022]
Abstract
Ligand binding to polymers modifies the physical and chemical properties of the polymers, leading to physical, chemical, and biological implications. McGhee and von Hippel obtained the equilibrium coverage as a function of the ligand affinity, through the computation of the possible binding sites for the ligand. Here, we complete this theory deriving the kinetic model for the ligand-binding dynamics and the associated equilibrium chemical potential, which turns out to be of the Tonks gas model type. At low coverage, the Tonks chemical potential becomes the Fermi chemical potential and even the ideal gas chemical potential. We also discuss kinetic models associated with these chemical potentials. These results clarify the kinetic models of ligand binding, their relations with the chemical potentials, and their range of validity. Our results highlight the inaccuracy of ideal and simplified kinetic approaches for medium and high coverages.
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Affiliation(s)
- Juan P G Villaluenga
- Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid, Pza. de Ciencias, 1, 28040 Madrid, Spain
| | - Jules Vidal
- Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid, Pza. de Ciencias, 1, 28040 Madrid, Spain
| | - Francisco Javier Cao-García
- Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid, Pza. de Ciencias, 1, 28040 Madrid, Spain.,Instituto Madrileño de Estudios Avanzados en Nanociencia, IMDEA Nanociencia, C/Faraday, 9, 28049 Madrid, Spain
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11
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Alves PS, Mesquita ON, Rocha MS. Model for DNA Interactions with Proteins and Other Large Ligands: Extracting Physical Chemistry from Pure Mechanical Measurements. J Phys Chem B 2020; 124:1020-1024. [DOI: 10.1021/acs.jpcb.0c00155] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- P. S. Alves
- Instituto Federal de Educaçào, Ciência e Tecnologia de Minas Gerais, Santa Luzia, Minas Gerais 30575-180, Brazil
- Departamento de Fı́sica, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 31270-901 Brazil
| | - O. N. Mesquita
- Departamento de Fı́sica, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 31270-901 Brazil
| | - M. S. Rocha
- Departamento de Fı́sica, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900 Brazil
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12
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Lima CHM, Caquito JM, de Oliveira RM, Rocha MS. Pixantrone anticancer drug as a DNA ligand: Depicting the mechanism of action at single molecule level. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2019; 42:130. [PMID: 31583481 DOI: 10.1140/epje/i2019-11895-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 09/04/2019] [Indexed: 06/10/2023]
Abstract
In this work we use single molecule force spectroscopy performed with optical tweezers in order to characterize the complexes formed between the anticancer drug Pixantrone (PIX) and the DNA molecule, at two very different ionic strengths. Firstly, the changes of the mechanical properties of the DNA-PIX complexes were studied as a function of the drug concentration in the sample. Then, a quenched-disorder statistical model of ligand binding was used in order to determine the physicochemical (binding) parameters of the DNA-PIX interaction. In particular, we have found that the PIX molecular mechanism of action involves intercalation into the double helix, followed by a significant compaction of the DNA molecule due to partial neutralization of the phosphate backbone. Finally, this scenario of interaction was quantitatively compared to that found for the related drug Mitoxantrone (MTX), which binds to DNA with a considerably higher equilibrium binding constant and promotes a much stronger DNA compaction. The comparison performed between the two drugs can bring clues to the development of new (and more efficient) related compounds.
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Affiliation(s)
- C H M Lima
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - J M Caquito
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - R M de Oliveira
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - M S Rocha
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil.
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13
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Oliveira L, Caquito Jr JM, Rocha MS. Oxaliplatin effects on the DNA molecule studied by force spectroscopy. Biomed Phys Eng Express 2019. [DOI: 10.1088/2057-1976/ab37ce] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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14
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Moura T, Oliveira L, Rocha M. Effects of caffeine on the structure and conformation of DNA: A force spectroscopy study. Int J Biol Macromol 2019; 130:1018-1024. [DOI: 10.1016/j.ijbiomac.2019.02.125] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 02/21/2019] [Accepted: 02/21/2019] [Indexed: 10/27/2022]
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15
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Nascimento FR, Moura TA, Baeta JV, Publio BC, Ferreira PM, Santos AA, França AA, Rocha MS, Diaz-Muñoz G, Diaz MA. New antineoplastic agent based on a dibenzoylmethane derivative: Cytotoxic effect and direct interaction with DNA. Biophys Chem 2018; 239:1-6. [DOI: 10.1016/j.bpc.2018.04.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 04/28/2018] [Accepted: 04/28/2018] [Indexed: 11/26/2022]
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16
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Publio B, Moura T, Lima C, Rocha M. Biophysical characterization of the DNA interaction with the biogenic polyamine putrescine: A single molecule study. Int J Biol Macromol 2018; 112:175-178. [DOI: 10.1016/j.ijbiomac.2018.01.142] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 01/19/2018] [Accepted: 01/20/2018] [Indexed: 02/07/2023]
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17
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18
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Oliveira L, Rocha MS. Force spectroscopy unravels the role of ionic strength on DNA-cisplatin interaction: Modulating the binding parameters. Phys Rev E 2017; 96:032408. [PMID: 29346883 DOI: 10.1103/physreve.96.032408] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Indexed: 06/07/2023]
Abstract
In the present work we have gone a step forward in the understanding of the DNA-cisplatin interaction, investigating the role of the ionic strength on the complexes formation. To achieve this task, we use optical tweezers to perform force spectroscopy on the DNA-cisplatin complexes, determining their mechanical parameters as a function of the drug concentration in the sample for three different buffers. From such measurements, we determine the binding parameters and study their behavior as a function of the ionic strength. The equilibrium binding constant decreases with the counterion concentration ([Na]) and can be used to estimate the effective net charge of cisplatin in solution. The cooperativity degree of the binding reaction, on the other hand, increases with the ionic strength, as a result of the different conformational changes induced by the drug on the double-helix when binding under different buffer conditions. Such results can be used to modulate the drug binding to DNA, by appropriately setting the ionic strength of the surrounding buffer. The conclusions drawn provide significant new insights on the complex cooperative interactions between the DNA molecule and the class of platinum-based compounds, much used in chemotherapies.
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Affiliation(s)
- L Oliveira
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa. Viçosa, Minas Gerais, Brazil
| | - M S Rocha
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa. Viçosa, Minas Gerais, Brazil
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19
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Rocha JCB, Silva EF, Oliveira MF, Sousa FB, Teixeira AVNC, Rocha MS. β-Cyclodextrin polymer binding to DNA: Modulating the physicochemical parameters. Phys Rev E 2017; 95:052416. [PMID: 28618573 DOI: 10.1103/physreve.95.052416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Indexed: 11/07/2022]
Abstract
Cyclodextrins and cyclodextrins-modified molecules have interesting and appealing properties due to their capacity to host components that are normally insoluble or poorly soluble in water. In this work, we investigate the interaction of a β-cyclodextrin polymer (poly-β-CD) with λ-DNA. The polymers are obtained by the reaction of β-CD with epichlorohydrin in alkaline conditions. We have used optical tweezers to characterize the changes of the mechanical properties of DNA molecules by increasing the concentration of poly-β-CD in the sample. The physical chemistry of the interaction is then deduced from these measurements by using a recently developed quenched-disorder statistical model. It is shown that the contour length of the DNA does not change in the whole range of poly-β-CD concentration (<300μM). On the other hand, significant alterations were observed in the persistence length that identifies two binding modes corresponding to the clustering of ∼2.6 and ∼14 polymer molecules along the DNA double helix, depending on the polymer concentration. Comparing these results with the ones obtained for monomeric β-CD, it was observed that the concentration of CD that alters the DNA persistence length is considerably smaller when in the polymeric form. Also, the binding constant of the polymer-DNA interaction is three orders of magnitude higher than the one found for native (monomeric) β-CD. These results show that the polymerization of the β-CD strongly increases its binding affinity to the DNA molecule. This property can be wisely used to modulate the binding of cyclodextrins to the DNA double helix.
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Affiliation(s)
- J C B Rocha
- Departamento de Física, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil.,Instituto Federal do Norte de Minas Gerais-Campus Avançado Janaúba, 39440-000 Janaúba, MG, Brazil
| | - E F Silva
- Departamento de Física, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil
| | - M F Oliveira
- Departamento de Química, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil
| | - F B Sousa
- Instituto de Física e Química, Universidade Federal de Itajubá, 37500-903 Itajubá, MG, Brazil
| | - A V N C Teixeira
- Departamento de Física, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil
| | - M S Rocha
- Departamento de Física, Universidade Federal de Viçosa, 36570-900 Viçosa, MG, Brazil
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Jarillo J, Morín JA, Beltrán-Heredia E, Villaluenga JPG, Ibarra B, Cao FJ. Mechanics, thermodynamics, and kinetics of ligand binding to biopolymers. PLoS One 2017; 12:e0174830. [PMID: 28380044 PMCID: PMC5381885 DOI: 10.1371/journal.pone.0174830] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Accepted: 03/15/2017] [Indexed: 01/20/2023] Open
Abstract
Ligands binding to polymers regulate polymer functions by changing their physical and chemical properties. This ligand regulation plays a key role in many biological processes. We propose here a model to explain the mechanical, thermodynamic, and kinetic properties of the process of binding of small ligands to long biopolymers. These properties can now be measured at the single molecule level using force spectroscopy techniques. Our model performs an effective decomposition of the ligand-polymer system on its covered and uncovered regions, showing that the elastic properties of the ligand-polymer depend explicitly on the ligand coverage of the polymer (i.e., the fraction of the polymer covered by the ligand). The equilibrium coverage that minimizes the free energy of the ligand-polymer system is computed as a function of the applied force. We show how ligands tune the mechanical properties of a polymer, in particular its length and stiffness, in a force dependent manner. In addition, it is shown how ligand binding can be regulated applying mechanical tension on the polymer. Moreover, the binding kinetics study shows that, in the case where the ligand binds and organizes the polymer in different modes, the binding process can present transient shortening or lengthening of the polymer, caused by changes in the relative coverage by the different ligand modes. Our model will be useful to understand ligand-binding regulation of biological processes, such as the metabolism of nucleic acid. In particular, this model allows estimating the coverage fraction and the ligand mode characteristics from the force extension curves of a ligand-polymer system.
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Affiliation(s)
- Javier Jarillo
- Departamento de Física Atómica, Molecular y Nuclear. Facultad de Ciencias Físicas. Universidad Complutense de Madrid. Pza. de las Ciencias, 1. Madrid. Spain
| | - José A. Morín
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia) & CNB-CSIC-IMDEA Nanociencia Associated Unit ‘Unidad de Nanobiotecnología’, Madrid, Spain
| | - Elena Beltrán-Heredia
- Departamento de Física Atómica, Molecular y Nuclear. Facultad de Ciencias Físicas. Universidad Complutense de Madrid. Pza. de las Ciencias, 1. Madrid. Spain
| | - Juan P. G. Villaluenga
- Departamento de Física Aplicada I. Facultad de Ciencias Físicas. Universidad Complutense de Madrid. Pza. de las Ciencias, 1. Madrid. Spain
| | - Borja Ibarra
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia) & CNB-CSIC-IMDEA Nanociencia Associated Unit ‘Unidad de Nanobiotecnología’, Madrid, Spain
| | - Francisco J. Cao
- Departamento de Física Atómica, Molecular y Nuclear. Facultad de Ciencias Físicas. Universidad Complutense de Madrid. Pza. de las Ciencias, 1. Madrid. Spain
- * E-mail:
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21
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Reis LA, Rocha MS. DNA interaction with DAPI fluorescent dye: Force spectroscopy decouples two different binding modes. Biopolymers 2017; 107. [DOI: 10.1002/bip.23015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 01/13/2017] [Accepted: 01/18/2017] [Indexed: 01/10/2023]
Affiliation(s)
- L. A. Reis
- Laboratório de Física Biológica, Departamento de Física; Universidade Federal de Viçosa; Minas Gerais Brazil
| | - M. S. Rocha
- Laboratório de Física Biológica, Departamento de Física; Universidade Federal de Viçosa; Minas Gerais Brazil
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22
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Silva EF, Bazoni RF, Ramos EB, Rocha MS. DNA-doxorubicin interaction: New insights and peculiarities. Biopolymers 2017; 107. [PMID: 27718222 DOI: 10.1002/bip.22998] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 09/25/2016] [Accepted: 10/05/2016] [Indexed: 12/18/2022]
Abstract
We have investigated the interaction of the DNA molecule with the anticancer drug doxorubicin (doxo) by using three different experimental techniques: single molecule stretching, single molecule imaging, and dynamic light scattering. Such techniques allowed us to get new insights on the mechanical behavior of the DNA-doxo complexes as well as on the physical chemistry of the interaction. First, the contour length data obtained from single molecule stretching were used to extract the physicochemical parameters of the DNA-doxo interaction under different buffer conditions. This analysis has proven that the physical chemistry of such interaction can be modulated by changing the ionic strength of the surrounding buffer. In particular we have found that at low ionc strengths doxo interacts with DNA by simple intercalation (no aggregation) and/or by forming bound dimers. For high ionic strengths, otherwise, doxo-doxo self-association is enhanced, giving rise to the formation of bound doxo aggregates composed by 3 to 4 molecules along the double-helix. On the other hand, the results obtained for the persistence length of the DNA-doxo complexes is strongly force-dependent, presenting different behaviors when measured with stretching or non-stretching techniques.
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Affiliation(s)
- E F Silva
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - R F Bazoni
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - E B Ramos
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - M S Rocha
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
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Leclercq L. Interactions between cyclodextrins and cellular components: Towards greener medical applications? Beilstein J Org Chem 2016; 12:2644-2662. [PMID: 28144335 PMCID: PMC5238526 DOI: 10.3762/bjoc.12.261] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 11/25/2016] [Indexed: 11/23/2022] Open
Abstract
In the field of host-guest chemistry, some of the most widely used hosts are probably cyclodextrins (CDs). As CDs are able to increase the water solubility of numerous drugs by inclusion into their hydrophobic cavity, they have been widespread used to develop numerous pharmaceutical formulations. Nevertheless, CDs are also able to interact with endogenous substances that originate from an organism, tissue or cell. These interactions can be useful for a vast array of topics including cholesterol manipulation, treatment of Alzheimer's disease, control of pathogens, etc. In addition, the use of natural CDs offers the great advantage of avoiding or reducing the use of common petroleum-sourced drugs. In this paper, the general features and applications of CDs have been reviewed as well as their interactions with isolated biomolecules leading to the formation of inclusion or exclusion complexes. Finally, some potential medical applications are highlighted throughout several examples.
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Affiliation(s)
- Loïc Leclercq
- Univ. Lille, CNRS, ENSCL, UMR 8181 – UCCS - Equipe CÏSCO, F-59000 Lille, France
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24
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Bernal WFP, Silva EF, Rocha MS. Unraveling the physical chemistry and the mixed binding modes of complex DNA ligands by single molecule stretching experiments. RSC Adv 2016. [DOI: 10.1039/c6ra22980h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
In this work we present a complete methodology to unravel the physical chemistry and the mixed binding modes of complex DNA ligands.
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Affiliation(s)
- W. F. P. Bernal
- Laboratório de Física Biológica
- Departamento de Física
- Universidade Federal de Viçosa
- Viçosa
- Brazil
| | - E. F. Silva
- Laboratório de Física Biológica
- Departamento de Física
- Universidade Federal de Viçosa
- Viçosa
- Brazil
| | - M. S. Rocha
- Laboratório de Física Biológica
- Departamento de Física
- Universidade Federal de Viçosa
- Viçosa
- Brazil
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Abstract
We have investigated the interaction between the native neutral β-cyclodextrin (CD) and the DNA molecule by performing single-molecule stretching experiments with optical tweezers. In particular, we have monitored the changes of the mechanical properties of the CD-DNA complexes as a function of the CD concentration in the sample. By using a quenched disorder statistical model, we were also capable to extract important physicochemical information (equilibrium binding constants, cooperativity degree) of such interaction from the mechanical data. In addition, we have found that the interaction occurs by two different mechanisms, first with the formation of relatively large CD clusters along the double helix, which thereafter can locally denature the DNA molecule by forming hydrogen bonds with the base pairs that eventually flip out. A prediction of our quenched disorder model was that cooperativity could be controlled by adjusting the surface charge of β-CD molecules. This prediction is confirmed in the present work.
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Affiliation(s)
- P S Alves
- Departamento de Física, Universidade Federal de Minas Gerais , Av. Antônio Carlos, 6627, Belo Horizonte, Minas Gerais 31270-901, Brazil
| | - O N Mesquita
- Departamento de Física, Universidade Federal de Minas Gerais , Av. Antônio Carlos, 6627, Belo Horizonte, Minas Gerais 31270-901, Brazil
| | - M S Rocha
- Departamento de Física, Universidade Federal de Viçosa , Av. P. H. Rolfs s/n, Viçosa, Minas Gerais 36570-900, Brazil
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Bazoni RF, Lima CHM, Ramos EB, Rocha MS. Force-dependent persistence length of DNA-intercalator complexes measured in single molecule stretching experiments. SOFT MATTER 2015; 11:4306-4314. [PMID: 25913936 DOI: 10.1039/c5sm00706b] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
By using optical tweezers with an adjustable trap stiffness, we have performed systematic single molecule stretching experiments with two types of DNA-intercalator complexes, in order to investigate the effects of the maximum applied forces on the mechanical response of such complexes. We have explicitly shown that even in the low-force entropic regime the persistence length of the DNA-intercalator complexes is strongly force-dependent, although such behavior is not exhibited by bare DNA molecules. We discuss the possible physicochemical effects that can lead to such results. In particular, we propose that the stretching force can promote partial denaturation on the highly distorted double-helix of the DNA-intercalator complexes, which interfere strongly in the measured values of the persistence length.
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Affiliation(s)
- R F Bazoni
- Laboratório de Física Biológica, Departamento de Física, Universidade Federal de Viçosa. Viçosa, Minas Gerais, Brazil.
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Rocha MS. Extracting physical chemistry from mechanics: a new approach to investigate DNA interactions with drugs and proteins in single molecule experiments. Integr Biol (Camb) 2015; 7:967-86. [DOI: 10.1039/c5ib00127g] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In this review we focus on the idea of establishing connections between the mechanical properties of DNA–ligand complexes and the physical chemistry of DNA–ligand interactions.
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Affiliation(s)
- M. S. Rocha
- Laboratório de Física Biológica
- Departamento de Física
- Universidade Federal de Viçosa
- Viçosa
- Brazil
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28
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Characterizing the interaction between DNA and GelRed fluorescent stain. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2014; 44:1-7. [DOI: 10.1007/s00249-014-0995-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 10/13/2014] [Accepted: 10/20/2014] [Indexed: 10/24/2022]
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Gadagkar SR, Call GB. Computational tools for fitting the Hill equation to dose-response curves. J Pharmacol Toxicol Methods 2014; 71:68-76. [PMID: 25157754 DOI: 10.1016/j.vascn.2014.08.006] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 08/15/2014] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Many biological response curves commonly assume a sigmoidal shape that can be approximated well by means of the 4-parameter nonlinear logistic equation, also called the Hill equation. However, estimation of the Hill equation parameters requires access to commercial software or the ability to write computer code. Here we present two user-friendly and freely available computer programs to fit the Hill equation - a Solver-based Microsoft Excel template and a stand-alone GUI-based "point and click" program, called HEPB. METHODS Both computer programs use the iterative method to estimate two of the Hill equation parameters (EC50 and the Hill slope), while constraining the values of the other two parameters (the minimum and maximum asymptotes of the response variable) to fit the Hill equation to the data. In addition, HEPB draws the prediction band at a user-defined confidence level, and determines the EC50 value for each of the limits of this band to give boundary values that help objectively delineate sensitive, normal and resistant responses to the drug being tested. RESULTS Both programs were tested by analyzing twelve datasets that varied widely in data values, sample size and slope, and were found to yield estimates of the Hill equation parameters that were essentially identical to those provided by commercial software such as GraphPad Prism and nls, the statistical package in the programming language R. DISCUSSION The Excel template provides a means to estimate the parameters of the Hill equation and plot the regression line in a familiar Microsoft Office environment. HEPB, in addition to providing the above results, also computes the prediction band for the data at a user-defined level of confidence, and determines objective cut-off values to distinguish among response types (sensitive, normal and resistant). Both programs are found to yield estimated values that are essentially the same as those from standard software such as GraphPad Prism and the R-based nls. Furthermore, HEPB also has the option to simulate 500 response values based on the range of values of the dose variable in the original data and the fit of the Hill equation to that data.
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Affiliation(s)
- Sudhindra R Gadagkar
- Department of Biomedical Sciences, College of Health Sciences, Midwestern University, Glendale, AZ 85308, USA.
| | - Gerald B Call
- Department of Pharmacology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ 85308, USA
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LeGresley SE, Wilt J, Antonik M. DNA damage may drive nucleosomal reorganization to facilitate damage detection. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:032708. [PMID: 24730875 DOI: 10.1103/physreve.89.032708] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Indexed: 06/03/2023]
Abstract
One issue in genome maintenance is how DNA repair proteins find lesions at rates that seem to exceed diffusion-limited search rates. We propose a phenomenon where DNA damage induces nucleosomal rearrangements which move lesions to potential rendezvous points in the chromatin structure. These rendezvous points are the dyad and the linker DNA between histones, positions in the chromatin which are more likely to be accessible by repair proteins engaged in a random search. The feasibility of this mechanism is tested by considering the statistical mechanics of DNA containing a single lesion wrapped onto the nucleosome. We consider lesions which make the DNA either more flexible or more rigid by modeling the lesion as either a decrease or an increase in the bending energy. We include this energy in a partition function model of nucleosome breathing. Our results indicate that the steady state for a breathing nucleosome will most likely position the lesion at the dyad or in the linker, depending on the energy of the lesion. A role for DNA binding proteins and chromatin remodelers is suggested based on their ability to alter the mechanical properties of the DNA and DNA-histone binding, respectively. We speculate that these positions around the nucleosome potentially serve as rendezvous points where DNA lesions may be encountered by repair proteins which may be sterically hindered from searching the rest of the nucleosomal DNA. The strength of the repositioning is strongly dependent on the structural details of the DNA lesion and the wrapping and breathing of the nucleosome. A more sophisticated evaluation of this proposed mechanism will require detailed information about breathing dynamics, the structure of partially wrapped nucleosomes, and the structural properties of damaged DNA.
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Affiliation(s)
- Sarah E LeGresley
- Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045, USA
| | - Jamie Wilt
- Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045, USA
| | - Matthew Antonik
- Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045, USA
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Reis LA, Ramos EB, Rocha MS. DNA Interaction with Diaminobenzidine Studied with Optical Tweezers and Dynamic Light Scattering. J Phys Chem B 2013; 117:14345-50. [DOI: 10.1021/jp409544e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- L. A. Reis
- Laboratório de Física
Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - E. B. Ramos
- Laboratório de Física
Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - M. S. Rocha
- Laboratório de Física
Biológica, Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
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32
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Silva EF, Ramos EB, Rocha MS. DNA Interaction with Hoechst 33258: Stretching Experiments Decouple the Different Binding Modes. J Phys Chem B 2013; 117:7292-6. [DOI: 10.1021/jp403945e] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- E. F. Silva
- Laboratório de Física
Biológica,
Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - E. B. Ramos
- Laboratório de Física
Biológica,
Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
| | - M. S. Rocha
- Laboratório de Física
Biológica,
Departamento de Física, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil
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Cesconetto EC, Junior FSA, Crisafuli FAP, Mesquita ON, Ramos EB, Rocha MS. DNA interaction with Actinomycin D: mechanical measurements reveal the details of the binding data. Phys Chem Chem Phys 2013; 15:11070-7. [DOI: 10.1039/c3cp50898f] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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