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Koroleva ON, Kuzmina NV, Dubrovin EV, Drutsa VL. Atomic force microscopy of spherical intermediates on the pathway to fibril formation of influenza A virus nuclear export protein. Microsc Res Tech 2024; 87:1131-1145. [PMID: 38270267 DOI: 10.1002/jemt.24499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 01/02/2024] [Accepted: 01/07/2024] [Indexed: 01/26/2024]
Abstract
The nuclear export protein of the influenza A virus (NEP) is involved in many important processes of the virus life cycle. This makes it an attractive target for the treatment of a disease caused by a virus. Previously it has been shown, that recombinant variants of NEP are highly prone to aggregation in solution under various conditions with the formation of amyloid-like aggregates. In the present work, the amyloid nature of NEP aggregates was evidenced by Congo red binding assays. Atomic force microscopy has shown that NEP can form two types of spherical nanoparticles, which provide an alternative pathway for the formation of amyloid-like fibrils. Type I of these "fibrillogenic" spheres, formed under physiological conditions, represents the micelle-like particles with height 10-60 nm, which can generate worm-like flexible fibrils with the diameter 2.5-4.0 nm, length 20-500 nm and the Young's modulus ~73 MPa. Type II spherical aggregates with size of about 400-1000 nm, formed at elevated temperatures, includes fractions of drop-like and vesicle-like particles, generating more rigid amyloid-like fibrils with height of ~8 nm, and length of up to 2 μm. The hypothetical mechanism of fibril formation via nanospherical structures was suggested. RESEARCH HIGHLIGHTS: AFM has revealed two types of the influenza A virus nuclear export protein spherical aggregates. They provide an alternative pathway for the formation of amyloid-like fibrils. The mechanism of fibril formation via spherical structures is suggested.
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Affiliation(s)
- Olga N Koroleva
- Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Natalia V Kuzmina
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Evgeniy V Dubrovin
- Faculty of Physics, Lomonosov Moscow State University, Moscow, Russian Federation
- National University of Science and Technology, MISIS, Moscow, Russian Federation
| | - Valeriy L Drutsa
- A.N.Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
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Barinov NA, Ivanov DA, Dubrovin EV, Klinov DV. Atomic force microscopy investigation of DNA denaturation on a highly oriented pyrolytic graphite surface. Int J Biol Macromol 2024; 267:131630. [PMID: 38631581 DOI: 10.1016/j.ijbiomac.2024.131630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 04/06/2024] [Accepted: 04/13/2024] [Indexed: 04/19/2024]
Abstract
Understanding of DNA interaction with carbonaceous surfaces (including graphite, graphene and carbon nanotubes) is important for the development of DNA-based biosensors and other biotechnological devices. Though many issues related to DNA adsorption on graphitic surfaces have been studied, some important aspects of DNA interaction with graphite remain unclear. In this work, we use atomic force microscopy (AFM) equipped with super-sharp cantilevers to analyze the morphology and conformation of relatively long DNA molecule adsorbed on a highly oriented pyrolytic graphite (HOPG) surface. We have revealed the effect of DNA embedding into an organic monolayer of N,N'-(decane-1,10-diyl)-bis(tetraglycinamide) (GM), which may "freeze" DNA conformation on a HOPG surface during drying. The dependence of the mean squared point-to-point distance on the contour length suggests that DNA adsorbs on a bare HOPG by a "kinetic trapping" mechanism. For the first time, we have estimated the unfolded fraction of DNA upon contact with a HOPG surface (24 ± 5 %). The obtained results represent a novel experimental model for investigation of the conformation and morphology of DNA adsorbed on graphitic surfaces and provide with a new insight into DNA interaction with graphite.
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Affiliation(s)
- Nikolay A Barinov
- Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny 141700, Russian Federation; Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russian Federation
| | - Dmitry A Ivanov
- Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russian Federation; Institut de Sciences des Matériaux de Mulhouse - IS2M, CNRS UMR7361, 15 Jean Starcky, Mulhouse 68057, France
| | - Evgeniy V Dubrovin
- Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny 141700, Russian Federation; Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russian Federation; Lomonosov Moscow State University, Leninskie Gory 1 bld. 2, 119991 Moscow, Russian Federation.
| | - Dmitry V Klinov
- Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny 141700, Russian Federation; Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russian Federation.
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Dubrovin EV. Atomic force microscopy-based approaches for single-molecule investigation of nucleic acid- protein complexes. Biophys Rev 2023; 15:1015-1033. [PMID: 37974971 PMCID: PMC10643717 DOI: 10.1007/s12551-023-01111-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 08/07/2023] [Indexed: 11/19/2023] Open
Abstract
The interaction of nucleic acids with proteins plays an important role in many fundamental biological processes in living cells, including replication, transcription, and translation. Therefore, understanding nucleic acid-protein interaction is of high relevance in many areas of biology, medicine and technology. During almost four decades of its existence atomic force microscopy (AFM) accumulated a significant experience in investigation of biological molecules at a single-molecule level. AFM has become a powerful tool of molecular biology and biophysics providing unique information about properties, structure, and functioning of biomolecules. Despite a great variety of nucleic acid-protein systems under AFM investigations, there are a number of typical approaches for such studies. This review is devoted to the analysis of the typical AFM-based approaches of investigation of DNA (RNA)-protein complexes with a major focus on transcription studies. The basic strategies of AFM analysis of nucleic acid-protein complexes including investigation of the products of DNA-protein reactions and real-time dynamics of DNA-protein interaction are categorized and described by the example of the most relevant research studies. The described approaches and protocols have many universal features and, therefore, are applicable for future AFM studies of various nucleic acid-protein systems.
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Affiliation(s)
- Evgeniy V. Dubrovin
- Lomonosov Moscow State University, Leninskie Gory 1 Bld. 2, 119991 Moscow, Russian Federation
- Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny, 141700 Russian Federation
- Sirius University of Science and Technology, Olimpiyskiy Ave 1, Township Sirius, Krasnodar Region, 354349 Russia
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Sergeeva IA, Klinov DV, Schäffer TE, Dubrovin EV. Characterization of the effect of chromium salts on tropocollagen molecules and molecular aggregates. Int J Biol Macromol 2023; 242:124835. [PMID: 37201883 DOI: 10.1016/j.ijbiomac.2023.124835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/06/2023] [Accepted: 05/08/2023] [Indexed: 05/20/2023]
Abstract
Though the capability of chromium treatment to improve the stability and mechanical properties of collagen fibrils is well-known, the influence of different chromium salts on collagen molecules (tropocollagen) is not well characterized. In this study, the effect of Cr3+ treatment on the conformation and hydrodynamic properties of collagen was studied using atomic force microscopy (AFM) and dynamic light scattering (DLS). Statistical analysis of contours of adsorbed tropocollagen molecules using the two-dimensional worm-like chain model revealed a reduction of the persistence length (i.e., the increase of flexibility) from ≈72 nm in water to ≈56-57 nm in chromium (III) salt solutions. DLS studies demonstrated an increase of the hydrodynamic radius from ≈140 nm in water to ≈190 nm in chromium (III) salt solutions, which is associated with protein aggregation. The kinetics of collagen aggregation was shown to be ionic strength dependent. Collagen molecules treated with three different chromium (III) salts demonstrated similar properties such as flexibility, aggregation kinetics, and susceptibility to enzymatic cleavage. The observed effects are explained by a model that considers the formation of chromium-associated intra- and intermolecular crosslinks. The obtained results provide novel insights into the effect of chromium salts on the conformation and properties of tropocollagen molecules.
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Affiliation(s)
- Irina A Sergeeva
- Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory 1 bld 2, 119991 Moscow, Russia.
| | - Dmitry V Klinov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya 1a, 119435 Moscow, Russia
| | - Tilman E Schäffer
- University of Tübingen, Institute of Applied Physics, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Evgeniy V Dubrovin
- Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory 1 bld 2, 119991 Moscow, Russia.
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Dubrovin EV, Barinov NA, Ivanov DA, Klinov DV. Single-molecule AFM study of hyaluronic acid softening in electrolyte solutions. Carbohydr Polym 2023; 303:120472. [PMID: 36657830 DOI: 10.1016/j.carbpol.2022.120472] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 11/30/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
Abstract
Investigation of hyaluronic acid (HA) morphology and mechanical properties at a single-molecule level is important for the development of HA based biomaterials. We have developed the atomic force microscopy (AFM) based approach for quantitative characterization of conformation of HA molecules. HA molecules adsorbed on a modified graphitic surface form oriented linear segments. Conformation of HA molecules can be considered as two-dimensional quasi-projection of a three-dimensional conformation locally straightened by a substrate. The persistence length and Young's modulus of biomolecules estimated using wormlike chain model decrease from 15.7 to 9.9 nm, and from ∼21 to ∼13 GPa, respectively, when KCl concentration increases from 0 to 100 mM. The dependence of the persistence length on ionic strength supports the Odijk-Skolnick-Fixman model of polyelectrolyte stiffening in electrolyte solution. The obtained results represent a new insight into the conformation and mechanical characteristics of HA molecules and complement the characterization of this biopolymer by bulk methods.
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Affiliation(s)
- Evgeniy V Dubrovin
- Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russian Federation; Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny 141700, Russian Federation; Lomonosov Moscow State University, Leninskie Gory 1 bld. 2, 119991 Moscow, Russian Federation.
| | - Nikolay A Barinov
- Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russian Federation; Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny 141700, Russian Federation.
| | - Dmitry A Ivanov
- Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russian Federation; Institut de Sciences des Matériaux de Mulhouse - IS2M, CNRS UMR7361, 15 Jean Starcky, Mulhouse 68057, France.
| | - Dmitry V Klinov
- Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russian Federation; Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny 141700, Russian Federation.
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Dubrovin EV, Barinov NA, Klinov DV. Visualization of G-Quadruplexes, i-Motifs and Their Associates. Acta Naturae 2022; 14:4-18. [DOI: 10.32607/actanaturae.11705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 07/13/2022] [Indexed: 11/20/2022] Open
Abstract
The non-canonical structures formed by G- or C-rich DNA regions, such as quadruplexes and i-motifs, as well as their associates, have recently been attracting increasing attention both because of the arguments in favor of their existence in vivo and their potential application in nanobiotechnology. When studying the structure and properties of non-canonical forms of DNA, as well as when controlling the artificially created architectures based on them, visualization plays an important role. This review analyzes the methods used to visualize quadruplexes, i-motifs, and their associates with high spatial resolution: fluorescence microscopy, transmission electron microscopy (TEM), and atomic force microscopy (AFM). The key approaches to preparing specimens for the visualization of this type of structures are presented. Examples of visualization of non-canonical DNA structures having various morphologies, such as G-wires, G-loops, as well as individual quadruplexes, i-motifs and their associates, are considered. The potential for using AFM for visualizing non-canonical DNA structures is demonstrated.
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Barinov NA, Pavlova ER, Tolstova AP, Matveeva AG, Moskalets AP, Dubrovin EV, Klinov DV. Myeloperoxidase-induced fibrinogen unfolding and clotting. Microsc Res Tech 2022; 85:2537-2548. [PMID: 35315962 DOI: 10.1002/jemt.24107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 02/19/2022] [Accepted: 03/03/2022] [Indexed: 11/08/2022]
Abstract
Due to its unique properties and high biomedical relevance fibrinogen is a promising protein for the development of various matrixes and scaffolds for biotechnological applications. Fibrinogen molecules may form extensive clots either upon specific cleavage by thrombin or in thrombin-free environment, for example, in the presence of different salts. Here, we report the novel type of non-conventional fibrinogen clot formation, which is mediated by myeloperoxidase and takes place even at low fibrinogen concentrations (<0.1 mg/ml). We have revealed fibrillar nature of myeloperoxidase-mediated fibrinogen clots, which differ morphologically from fibrin clots. We have shown that fibrinogen clotting is mediated by direct interaction of myeloperoxidase molecules with the outer globular regions of fibrinogen molecules followed by fibrinogen unfolding from its natural trinodular to a fibrillar structure. We have demonstrated a major role of the Debye screening effect in regulating of myeloperoxidase-induced fibrinogen clotting, which is facilitated by small ionic strength. While fibrinogen in an aqueous solution with myeloperoxidase undergoes changes, the enzymatic activity of myeloperoxidase is not inhibited in excess of fibrinogen. The obtained results open new insights into fibrinogen clotting, give new possibilities for the development of fibrinogen-based functional biomaterials, and provide the novel concepts of protein unfolding.
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Affiliation(s)
- Nikolay A Barinov
- Department of Biophysics, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russian Federation.,Scientific and educational resource center for innovative technologies of immunophenotyping, digital spatial profiling and ultrastructural analysis (molecular morphology), Peoples' Friendship University of Russia (RUDN University), Moscow, Russian Federation
| | - Elizaveta R Pavlova
- Department of Biophysics, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russian Federation.,Scientific and educational resource center for innovative technologies of immunophenotyping, digital spatial profiling and ultrastructural analysis (molecular morphology), Peoples' Friendship University of Russia (RUDN University), Moscow, Russian Federation
| | - Anna P Tolstova
- Laboratory of protein conformational polymorphism in health and disease, Engelhardt Institute of Molecular Biology, Moscow, Russian Federation
| | - Ainur G Matveeva
- Department of Biophysics, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russian Federation.,Scientific and educational resource center for innovative technologies of immunophenotyping, digital spatial profiling and ultrastructural analysis (molecular morphology), Peoples' Friendship University of Russia (RUDN University), Moscow, Russian Federation
| | - Aleksandr P Moskalets
- Department of Biophysics, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russian Federation
| | - Evgeniy V Dubrovin
- Department of Biophysics, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russian Federation.,Scientific and educational resource center for innovative technologies of immunophenotyping, digital spatial profiling and ultrastructural analysis (molecular morphology), Peoples' Friendship University of Russia (RUDN University), Moscow, Russian Federation.,Faculty of Physics, Lomonosov Moscow State University, Moscow, Russian Federation.,Laboratory of Biophysics, National University of Science and Technology MISIS, Moscow, Russian Federation
| | - Dmitry V Klinov
- Department of Biophysics, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russian Federation.,Scientific and educational resource center for innovative technologies of immunophenotyping, digital spatial profiling and ultrastructural analysis (molecular morphology), Peoples' Friendship University of Russia (RUDN University), Moscow, Russian Federation
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Barinov NA, Tolstova AP, Bersenev EA, Ivanov DA, Dubrovin EV, Klinov DV. Molecular patterns of oligopeptide hydrocarbons on graphite. Colloids Surf B Biointerfaces 2021; 206:111921. [PMID: 34157520 DOI: 10.1016/j.colsurfb.2021.111921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 05/19/2021] [Accepted: 06/13/2021] [Indexed: 10/21/2022]
Abstract
Graphitic materials including graphene, carbon nanotubes and fullerenes, are promising for use in nanotechnology and biomedicine. Non-covalent functionalization by peptides and other organic molecules allows changing the properties of graphitic surfaces in a controlled manner and represents a big potential for fundamental research and applications. Recently described oligopeptide-hydrocarbon derivative N,N'-(decane-1,10-diyl)bis(tetraglycineamide) (GM) is highly prospective for the development of graphitic interfaces in biosensor application as well as in structural biology for improving the quality of high-resolution atomic force microscopy (AFM) visualization of individual biomacromolecules. However, molecular organization of GM on graphitic surfaces is still unknown. In this work, the molecular model of GM at the water/highly oriented pyrolytic graphite (HOPG) interface has been developed basing on the high-resolution AFM and full-atom molecular modeling data. This model explains two periodicities observed in AFM images by GM self-assembly on a HOPG surface with formation of the stacks with the lateral shifts. The obtained results reveal the particular patterns and dynamics of GM molecules adsorbed on graphite and unravel the puzzle of peptide self-assembly on graphitic surfaces.
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Affiliation(s)
- Nikolay A Barinov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya 1a, Moscow 119435 Russian Federation; Sirius University of Science and Technology, 1 Olympic Ave, 354340, Sochi, Russian Federation
| | - Anna P Tolstova
- Engelhardt Institute of Molecular Biology, Vavilova 32, 119991, Moscow, Russian Federation
| | - Egor A Bersenev
- Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny 141700, Russian Federation; Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Russian Federation
| | - Dmitry A Ivanov
- Sirius University of Science and Technology, 1 Olympic Ave, 354340, Sochi, Russian Federation; Institut de Sciences des Matériaux de Mulhouse-IS2M, CNRS UMR 7361, 15, rue Jean Starcky, F-68057 Mulhouse, France
| | - Evgeniy V Dubrovin
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya 1a, Moscow 119435 Russian Federation; Lomonosov Moscow State University, Leninskie Gory 1 Bld. 2, 119991 Moscow, Russian Federation.
| | - Dmitry V Klinov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya 1a, Moscow 119435 Russian Federation; Sirius University of Science and Technology, 1 Olympic Ave, 354340, Sochi, Russian Federation.
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Prokhorov VV, Barinov NA, Prusakov KA, Dubrovin EV, Frank-Kamenetskii MD, Klinov DV. Anomalous Laterally Stressed Kinetically Trapped DNA Surface Conformations. Nanomicro Lett 2021; 13:130. [PMID: 34138333 PMCID: PMC8141082 DOI: 10.1007/s40820-021-00626-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
DNA kinking is inevitable for the highly anisotropic 1D-1D electrostatic interaction with the one-dimensionally periodically charged surface. The double helical structure of the DNA kinetically trapped on positively charged monomolecular films comprising the lamellar templates is strongly laterally stressed and extremely perturbed at the nanometer scale. The DNA kinetic trapping is not a smooth 3D-> 2D conformational flattening but is a complex nonlinear in-plane mechanical response (bending, tensile and unzipping) driven by the physics beyond the scope of the applicability of the linear worm-like chain approximation. Up to now, the DNA molecule adsorbed on a surface was believed to always preserve its native structure. This belief implies a negligible contribution of lateral surface forces during and after DNA adsorption although their impact has never been elucidated. High-resolution atomic force microscopy was used to observe that stiff DNA molecules kinetically trapped on monomolecular films comprising one-dimensional periodically charged lamellar templates as a single layer or as a sublayer are oversaturated by sharp discontinuous kinks and can also be locally melted and supercoiled. We argue that kink/anti-kink pairs are induced by an overcritical lateral bending stress (> 30 pNnm) inevitable for the highly anisotropic 1D-1D electrostatic interaction of DNA and underlying rows of positive surface charges. In addition, the unexpected kink-inducing mechanical instability in the shape of the template-directed DNA confined between the positively charged lamellar sides is observed indicating the strong impact of helicity. The previously reported anomalously low values of the persistence length of the surface-adsorbed DNA are explained by the impact of the surface-induced low-scale bending. The sites of the local melting and supercoiling are convincingly introduced as other lateral stress-induced structural DNA anomalies by establishing a link with DNA high-force mechanics. The results open up the study in the completely unexplored area of the principally anomalous kinetically trapped DNA surface conformations in which the DNA local mechanical response to the surface-induced spatially modulated lateral electrostatic stress is essentially nonlinear. The underlying rich and complex in-plane nonlinear physics acts at the nanoscale beyond the scope of applicability of the worm-like chain approximation.
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Affiliation(s)
- Valery V Prokhorov
- Federal Research and Clinical Center of Physical-Chemical Medicine, Malaya Pirogovskaya, 1a, Moscow, 119435, Russian Federation.
- A.N.Frumkin Institute of Physical Chemistry and Electrochemistry, RAS, Leninsky prospect 31, Moscow, 199071, Russian Federation.
| | - Nikolay A Barinov
- Federal Research and Clinical Center of Physical-Chemical Medicine, Malaya Pirogovskaya, 1a, Moscow, 119435, Russian Federation
| | - Kirill A Prusakov
- Federal Research and Clinical Center of Physical-Chemical Medicine, Malaya Pirogovskaya, 1a, Moscow, 119435, Russian Federation
- Moscow Institute of Physics and Technology, Institutskiy per. 9, Dolgoprudny, 141700, Moscow, Russian Federation
| | - Evgeniy V Dubrovin
- Federal Research and Clinical Center of Physical-Chemical Medicine, Malaya Pirogovskaya, 1a, Moscow, 119435, Russian Federation
- Lomonosov Moscow State University, Leninskie gory, 1-2, Moscow, 119991, Russian Federation
| | | | - Dmitry V Klinov
- Federal Research and Clinical Center of Physical-Chemical Medicine, Malaya Pirogovskaya, 1a, Moscow, 119435, Russian Federation.
- Moscow Institute of Physics and Technology, Institutskiy per. 9, Dolgoprudny, 141700, Moscow, Russian Federation.
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Dubrovin EV, Dadinova LA, Petoukhov MV, Soshinskaya EY, Mozhaev AA, Klinov DV, Schäffer TE, Shtykova EV, Batishchev OV. Spatial organization of Dps and DNA-Dps complexes. J Mol Biol 2021; 433:166930. [PMID: 33713674 DOI: 10.1016/j.jmb.2021.166930] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 02/24/2021] [Accepted: 03/05/2021] [Indexed: 02/04/2023]
Abstract
DNA co-crystallization with Dps family proteins is a fundamental mechanism, which preserves DNA in bacteria from harsh conditions. Though many aspects of this phenomenon are well characterized, the spatial organization of DNA in DNA-Dps co-crystals is not completely understood, and existing models need further clarification. To advance in this problem we have utilized atomic force microscopy (AFM) as the main structural tool, and small-angle X-scattering (SAXS) to characterize Dps as a key component of the DNA-protein complex. SAXS analysis in the presence of EDTA indicates a significantly larger radius of gyration for Dps than would be expected for the core of the dodecamer, consistent with the N-terminal regions extending out into solution and being accessible for interaction with DNA. In AFM experiments, both Dps protein molecules and DNA-Dps complexes adsorbed on mica or highly oriented pyrolytic graphite (HOPG) surfaces form densely packed hexagonal structures with a characteristic size of about 9 nm. To shed light on the peculiarities of DNA interaction with Dps molecules, we have characterized individual DNA-Dps complexes. Contour length evaluation has confirmed the non-specific character of Dps binding with DNA and revealed that DNA does not wrap Dps molecules in DNA-Dps complexes. Angle analysis has demonstrated that in DNA-Dps complexes a Dps molecule contacts with a DNA segment of ~6 nm in length. Consideration of DNA condensation upon complex formation with small Dps quasi-crystals indicates that DNA may be arranged along the rows of ordered protein molecules on a Dps sheet.
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Affiliation(s)
- Evgeniy V Dubrovin
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia; Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory 1 bld 2, 119991 Moscow, Russia.
| | - Liubov A Dadinova
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics," Russian Academy of Sciences, 119333 Moscow, Russia
| | - Maxim V Petoukhov
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics," Russian Academy of Sciences, 119333 Moscow, Russia
| | - Ekaterina Yu Soshinskaya
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics," Russian Academy of Sciences, 119333 Moscow, Russia
| | - Andrey A Mozhaev
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics," Russian Academy of Sciences, 119333 Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Dmitry V Klinov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya 1a, 119435 Moscow, Russia
| | - Tilman E Schäffer
- University of Tübingen, Institute of Applied Physics, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Eleonora V Shtykova
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics," Russian Academy of Sciences, 119333 Moscow, Russia
| | - Oleg V Batishchev
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia
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Dubrovin EV, Klinov DV, Schäffer TE. Evidence of (anti)metamorphic properties of modified graphitic surfaces obtained in real time at a single-molecule level. Colloids Surf B Biointerfaces 2020; 193:111077. [DOI: 10.1016/j.colsurfb.2020.111077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 04/09/2020] [Accepted: 04/21/2020] [Indexed: 12/31/2022]
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Kuzmina NV, Dubrovin EV, Koroleva ON, Drutsa VL, Zimmerberg J, Batishchev OV. Atomic Force Microscopy in the Study of Protein Self-Assembly. Biophys J 2020. [DOI: 10.1016/j.bpj.2019.11.1203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Tolstova AP, Dubrovin EV. Influence of pixelization on height measurement in atomic force microscopy. Ultramicroscopy 2019; 207:112846. [DOI: 10.1016/j.ultramic.2019.112846] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 05/31/2019] [Accepted: 09/12/2019] [Indexed: 10/26/2022]
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Erofeev AS, Gorelkin PV, Kolesov DV, Kiselev GA, Dubrovin EV, Yaminsky IV. Label-free sensitive detection of influenza virus using PZT discs with a synthetic sialylglycopolymer receptor layer. R Soc Open Sci 2019; 6:190255. [PMID: 31598281 PMCID: PMC6774986 DOI: 10.1098/rsos.190255] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 08/19/2019] [Indexed: 05/07/2023]
Abstract
We describe rapid, label-free detection of Influenza A viruses using the first radial mode of oscillations of lead zirconate titanate (PZT) piezoelectric discs with a 2 mm radius and 100 µm thickness fabricated from a piezoelectric membrane. The discs are modified with a synthetic sialylglycopolymer receptor layer, and the coated discs are inserted in a flowing virus suspension. Label-free detection of the virus is achieved by monitoring the disc radial mode resonance frequency shift. Piezo transducers with sialylglycopolymer sensor layers exhibited a long lifetime, a high sensitivity and the possibility of regeneration. We demonstrate positive, label-free detection of Influenza A viruses at concentrations below 105 virus particles per millilitre. We show that label-free, selective, sensitive detection of influenza viruses by home appliances is possible in principle.
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Affiliation(s)
- Alexander S. Erofeev
- Lomonosov Moscow State University, 1, Leninskie Gory, Moscow 119991, Russia
- National University of Science and Technology ‘MISIS’, Leninskiy prospect 4, 119991 Moscow, Russia
| | | | - Dmitry V. Kolesov
- FSBSI Institute of General Pathology and Pathophysiology, 8, Baltiyskaya st., Moscow 125315, Russia
| | - Gleb A. Kiselev
- Advanced Technologies Center, 4-5-47, Stroiteley Street, Moscow 119311, Russia
| | | | - Igor V. Yaminsky
- Lomonosov Moscow State University, 1, Leninskie Gory, Moscow 119991, Russia
- Advanced Technologies Center, 4-5-47, Stroiteley Street, Moscow 119311, Russia
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Erofeev AS, Gorelkin PV, Kolesov DV, Kiselev GA, Dubrovin EV, Yaminsky IV. Label-free sensitive detection of influenza virus using PZT discs with a synthetic sialylglycopolymer receptor layer. R Soc Open Sci 2019. [PMID: 31598281 DOI: 10.5061/dryad.6045tk0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We describe rapid, label-free detection of Influenza A viruses using the first radial mode of oscillations of lead zirconate titanate (PZT) piezoelectric discs with a 2 mm radius and 100 µm thickness fabricated from a piezoelectric membrane. The discs are modified with a synthetic sialylglycopolymer receptor layer, and the coated discs are inserted in a flowing virus suspension. Label-free detection of the virus is achieved by monitoring the disc radial mode resonance frequency shift. Piezo transducers with sialylglycopolymer sensor layers exhibited a long lifetime, a high sensitivity and the possibility of regeneration. We demonstrate positive, label-free detection of Influenza A viruses at concentrations below 105 virus particles per millilitre. We show that label-free, selective, sensitive detection of influenza viruses by home appliances is possible in principle.
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Affiliation(s)
- Alexander S Erofeev
- Lomonosov Moscow State University, 1, Leninskie Gory, Moscow 119991, Russia
- National University of Science and Technology 'MISIS', Leninskiy prospect 4, 119991 Moscow, Russia
| | | | - Dmitry V Kolesov
- FSBSI Institute of General Pathology and Pathophysiology, 8, Baltiyskaya st., Moscow 125315, Russia
| | - Gleb A Kiselev
- Advanced Technologies Center, 4-5-47, Stroiteley Street, Moscow 119311, Russia
| | - Evgeniy V Dubrovin
- Lomonosov Moscow State University, 1, Leninskie Gory, Moscow 119991, Russia
| | - Igor V Yaminsky
- Lomonosov Moscow State University, 1, Leninskie Gory, Moscow 119991, Russia
- Advanced Technologies Center, 4-5-47, Stroiteley Street, Moscow 119311, Russia
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16
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Dubrovin EV, Barinov NA, Schäffer TE, Klinov DV. In Situ Single-Molecule AFM Investigation of Surface-Induced Fibrinogen Unfolding on Graphite. Langmuir 2019; 35:9732-9739. [PMID: 31282164 DOI: 10.1021/acs.langmuir.9b01178] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Fibrinogen adsorption plays a key role in important biological processes, such as blood coagulation and foreign body reaction, which determine the biocompatibility of a material. Fibrinogen conformation on a surface is one of the main factors triggering these processes. Understanding the conformational dynamics of fibrinogen molecules adsorbed on solid surfaces is, therefore, of great interest in biomedicine and may contribute to the development of new biomaterials. In this work, unfolding of fibrinogen molecules adsorbed on a model surface (highly oriented pyrolytic graphite modified with an oligoglycine-hydrocarbon graphite modifier) is directly visualized using time-lapse atomic force microscopy. A gradual transformation of native-like fibrinogen molecules into fibrillar structures is observed at a timescale of several minutes. This transformation is accompanied by a decrease in molecular height from 4-5 to 1-2 nm. Independent unfolding of different fibrinogen domains is demonstrated. The obtained results provide a new, direct insight into the unfolding of individual fibrinogen molecules on a surface and give new opportunities for the development of graphite-based biosensors and biomaterials.
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Affiliation(s)
- Evgeniy V Dubrovin
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency , Malaya Pirogovskaya, 1a , Moscow 119435 , Russian Federation
- Institute of Applied Physics , University of Tübingen , Auf der Morgenstelle 10 , 72076 Tübingen , Germany
- Faculty of Physics , Lomonosov Moscow State University , Leninskie Gory, 1/2 , 119991 Moscow , Russian Federation
| | - Nikolay A Barinov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency , Malaya Pirogovskaya, 1a , Moscow 119435 , Russian Federation
| | - Tilman E Schäffer
- Institute of Applied Physics , University of Tübingen , Auf der Morgenstelle 10 , 72076 Tübingen , Germany
| | - Dmitry V Klinov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency , Malaya Pirogovskaya, 1a , Moscow 119435 , Russian Federation
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17
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Barinov NA, Vlasova II, Sokolov AV, Kostevich VA, Dubrovin EV, Klinov DV. High-resolution atomic force microscopy visualization of metalloproteins and their complexes. Biochim Biophys Acta Gen Subj 2018; 1862:2862-2868. [DOI: 10.1016/j.bbagen.2018.09.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 08/17/2018] [Accepted: 09/11/2018] [Indexed: 12/19/2022]
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Golovko AO, Koroleva ON, Tolstova AP, Kuz'mina NV, Dubrovin EV, Drutsa VL. Aggregation of Influenza A Virus Nuclear Export Protein. Biochemistry (Mosc) 2018; 83:1411-1421. [PMID: 30482152 DOI: 10.1134/s0006297918110111] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Influenza A virus nuclear export protein (NEP) plays an important role in the viral life cycle. Recombinant NEP proteins containing (His)6-tag at either N- or C-terminus were obtained by heterologous expression in Escherichia coli cells and their high propensity for aggregation was demonstrated. Dynamic light scattering technique was used to study the kinetics and properties of NEP aggregation in solutions under different conditions (pH, ionic strength, presence of low-molecular-weight additives and organic solvents). Using atomic force microscopy, the predominance of spherical aggregates in all examined NEP preparations was shown, with some amyloid-like structures being observed in the case of NEP-C protein. A number of structure prediction programs were used to identify aggregation-prone regions in the NEP structure. All-atom molecular dynamics simulations indicate a high rate of NEP molecule aggregation and reveal the regions preferentially involved in the intermolecular contacts that are located at the edges of the rod-like protein molecule. Our results suggest that NEP aggregation is determined by different types of interactions and represents an intrinsic property of the protein that appears to be necessary for its functioning in vivo.
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Affiliation(s)
- A O Golovko
- Lomonosov Moscow State University, Department of Bioengineering and Bioinformatics, Moscow, 119991, Russia.
| | - O N Koroleva
- Lomonosov Moscow State University, Department of Chemistry, Moscow, 119991, Russia.
| | - A P Tolstova
- Lomonosov Moscow State University, Department of Physics, Moscow, 119991, Russia.
| | - N V Kuz'mina
- Lomonosov Moscow State University, Department of Biology, Moscow, 119991, Russia. .,Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, 119071, Russia
| | - E V Dubrovin
- Lomonosov Moscow State University, Department of Physics, Moscow, 119991, Russia.
| | - V L Drutsa
- Lomonosov Moscow State University, Belozersky Research Institute of Physico-Chemical Biology, Moscow, 119991, Russia.
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Varizhuk AM, Protopopova AD, Tsvetkov VB, Barinov NA, Podgorsky VV, Tankevich MV, Vlasenok MA, Severov VV, Smirnov IP, Dubrovin EV, Klinov DV, Pozmogova GE. Polymorphism of G4 associates: from stacks to wires via interlocks. Nucleic Acids Res 2018; 46:8978-8992. [PMID: 30107602 PMCID: PMC6158749 DOI: 10.1093/nar/gky729] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 07/30/2018] [Accepted: 07/31/2018] [Indexed: 01/16/2023] Open
Abstract
We examined the assembly of DNA G-quadruplexes (G4s) into higher-order structures using atomic force microscopy, optical and electrophoretic methods, NMR spectroscopy and molecular modeling. Our results suggest that parallel blunt-ended G4s with single-nucleotide or modified loops may form different types of multimers, ranging from stacks of intramolecular structures and/or interlocked dimers and trimers to wires. Decreasing the annealing rate and increasing salt or oligonucleotide concentrations shifted the equilibrium from intramolecular G4s to higher-order structures. Control antiparallel and hybrid G4s demonstrated no polymorphism or aggregation in our experiments. The modification that mimics abasic sites (1',2'-dideoxyribose residues) in loops enhanced the oligomerization/multimerization of both the 2-tetrad and 3-tetrad G4 motifs. Our results shed light on the rules that govern G4 rearrangements. Gaining control over G4 folding enables the harnessing of the full potential of such structures for guided assembly of supramolecular DNA structures for nanotechnology.
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Affiliation(s)
- Anna M Varizhuk
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Anna D Protopopova
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Vladimir B Tsvetkov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Nikolay A Barinov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Victor V Podgorsky
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Maria V Tankevich
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Maria A Vlasenok
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Vyacheslav V Severov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Igor P Smirnov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Evgeniy V Dubrovin
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Dmitry V Klinov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Galina E Pozmogova
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
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Barinov NA, Protopopova AD, Dubrovin EV, Klinov DV. Thermal denaturation of fibrinogen visualized by single-molecule atomic force microscopy. Colloids Surf B Biointerfaces 2018; 167:370-376. [DOI: 10.1016/j.colsurfb.2018.04.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Revised: 04/08/2018] [Accepted: 04/17/2018] [Indexed: 01/27/2023]
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Dubrovin EV, Schächtele M, Klinov DV, Schäffer TE. Time-Lapse Single-Biomolecule Atomic Force Microscopy Investigation on Modified Graphite in Solution. Langmuir 2017; 33:10027-10034. [PMID: 28850785 DOI: 10.1021/acs.langmuir.7b02220] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Atomic force microscopy (AFM) of biomolecular processes at the single-molecule level can provide unique information for understanding molecular function. In AFM studies of biomolecular processes in solution, mica surfaces are predominantly used as substrates. However, owing to its high surface charge, mica may induce high local ionic strength in the vicinity of its surface, which may shift the equilibrium of studied biomolecular processes such as biopolymer adsorption or protein-DNA interaction. In the search for alternative substrates, we have investigated the behavior of adsorbed biomolecules, such as plasmid DNA and E. coli RNA polymerase σ70 subunit holoenzyme (RNAP), on highly oriented pyrolytic graphite (HOPG) surfaces modified with stearylamine and oligoglycine-hydrocarbon derivative (GM) monolayers using AFM in solution. We have demonstrated ionic-strength-dependent DNA mobility on GM HOPG and nativelike dimensions of RNAP molecules adsorbed on modified HOPG surfaces. We propose an approach to the real-time AFM investigation of transcription on stearylamine monolayers on graphite. We conclude that modified graphite allows us to study biomolecules and biomolecular processes on its surface at controlled ionic strength and may be used as a complement to mica in AFM investigations.
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Affiliation(s)
- Evgeniy V Dubrovin
- University of Tübingen , Institute of Applied Physics, Auf der Morgenstelle 10, 72076 Tübingen, Germany
- Federal Research and Clinical Center of Physical-Chemical Medicine , Malaya Pirogovskaya 1a, Moscow 119435, Russian Federation
- Lomonosov Moscow State University , Leninskie gory 1-2, Moscow 119991, Russian Federation
| | - Marc Schächtele
- University of Tübingen , Institute of Applied Physics, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Dmitry V Klinov
- Federal Research and Clinical Center of Physical-Chemical Medicine , Malaya Pirogovskaya 1a, Moscow 119435, Russian Federation
| | - Tilman E Schäffer
- University of Tübingen , Institute of Applied Physics, Auf der Morgenstelle 10, 72076 Tübingen, Germany
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Koroleva ON, Dubrovin EV, Yaminsky IV, Drutsa VL. Effect of DNA bending on transcriptional interference in the systems of closely spaced convergent promoters. Biochim Biophys Acta Gen Subj 2016; 1860:2086-96. [DOI: 10.1016/j.bbagen.2016.06.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 06/27/2016] [Accepted: 06/29/2016] [Indexed: 01/22/2023]
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Koroleva ON, Dubrovin EV, Tolstova AP, Kuzmina NV, Laptinskaya TV, Yaminsky IV, Drutsa VL. A hypothetical hierarchical mechanism of the self-assembly of the Escherichia coli RNA polymerase σ(70) subunit. Soft Matter 2016; 12:1974-1982. [PMID: 26758573 DOI: 10.1039/c5sm02934a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Diverse morphology of aggregates of amyloidogenic proteins has been attracting much attention in the last few years, and there is still no complete understanding of the relationships between various types of aggregates. In this work, we propose the model, which universally explains the formation of morphologically different (wormlike and rodlike) aggregates on the example of a σ(70) subunit of RNA polymerase, which has been recently shown to form amyloid fibrils. Aggregates were studied using AFM in solution and depolarized dynamic light scattering. The obtained results demonstrate comparably low Young's moduli of the wormlike structures (7.8-12.3 MPa) indicating less structured aggregation of monomeric proteins than that typical for β-sheet formation. To shed light on the molecular interaction of the protein during the aggregation, early stages of fibrillization of the σ(70) subunit were modeled using all-atom molecular dynamics. Simulations have shown that the σ(70) subunit is able to form quasi-symmetric extended dimers, which may further interact with each other and grow linearly. The proposed general model explains different pathways of σ(70) subunit aggregation and may be valid for other amyloid proteins.
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Affiliation(s)
- O N Koroleva
- Faculty of Chemistry, Lomonosov Moscow State University, Leninskie gory, 1/3, Moscow, 119991 Russian Federation
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Tolstova AP, Dubrovin EV, Koroleva ON. [Investigation of the Dependence of Escherichia coli RNA Polymerase σ70-Subunit Structure on Ionic Strength by Molecular Dynamics Simulation Method]. Biofizika 2015; 60:1045-1049. [PMID: 26841497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The σ70-subunit of E. coli RNA polymerase (a small protein, being a part of RNA holoenzyme, and responsible for initiation of transcription of constitutive genes) is modeled at different ionic strengths. Two variants of the location of C-end domain 4 are obtained. At low ionic strength domain 4 interacts with the region of high negative charge 190-210 AK within NCR domain. At high ionic strength this region was screened and domain 4 was free and set away from domain NCR. We suppose that this leads to the increase in polymerization rate. Simulation data do not confirm any hypothesis about a self-inhibition mechanism.
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Dubrovin EV, Presnova GV, Rubtsova MY, Grigorenko VG, Ivanin AI, Egorov AM, Yaminsky IV. [Implementation of scanning probe microscopy for the solution of molecular diagnostics tasks]. Biomed Khim 2015; 60:543-7. [PMID: 25386882 DOI: 10.18097/pbmc20146005543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We present new approaches to improve the efficiency of DNA by scanning probe microscopy using a highly specific hybridization on affine surfaces and nanostructures of gold as a labels. Scanning probe microscopy allows to register of individual acts of hybridization by the detection of gold labels on the surface affinity followed by automatic calculation of the total.
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Abstract
In this work, we have studied the conformation of DNA molecules aligned on the nanotemplates of octadecylamine, stearyl alcohol, and stearic acid on highly oriented pyrolytic graphite (HOPG). For this purpose, fluctuations of contours of adsorbed biopolymers obtained from atomic force microscopy (AFM) images were analyzed using the wormlike chain model. Moreover, the conformations of adsorbed biopolymer molecules were characterized by the analysis of the scaling exponent ν, which relates the mean squared end-to-end distance and contour length of the polymer. During adsorption on octadecylamine and stearyl alcohol nanotemplates, DNA forms straight segments, which order along crystallographic axes of graphite. In this case, the conformation of DNA molecules can be described using two different length scales. On a large length scale (at contour lengths l > 200-400 nm), aligned DNA molecules have either 2D compact globule or partially relaxed 2D conformation, whereas on a short length scale (at l ≤ 200-400 nm) their conformation is close to that of rigid rods. The latter type of conformation can be also assigned to DNA adsorbed on a stearic acid nanotemplate. The different conformation of DNA molecules observed on the studied monolayers is connected with the different DNA-nanotemplate interactions associated with the nature of the functional group of the alkane derivative in the nanotemplate (amine, alcohol, or acid). The persistence length of λ-DNA adsorbed on octadecylamine nanotemplates is 31 ± 2 nm indicating the loss of DNA rigidity in comparison with its native state. Similar values of the persistence length (34 ± 2 nm) obtained for 24-times shorter DNA molecules adsorbed on an octadecylamine nanotemplate demonstrate that this rigidity change does not depend on biopolymer length. Possible reasons for the reduction of DNA persistence length are discussed in view of the internal DNA structure and DNA-surface interaction.
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Affiliation(s)
- E V Dubrovin
- Chair of Physics of Polymers and Crystals, Faculty of Physics, M. V. Lomonosov Moscow State University , Leninskie gory, 1/2, Moscow 119991, Russia
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Koroleva ON, Dubrovin EV, Khodak YA, Kuzmina NV, Yaminsky IV, Drutsa VL. The model of amyloid aggregation of Escherichia coli RNA polymerase σ70 subunit based on AFM data and in vitro assays. Cell Biochem Biophys 2013; 66:623-36. [PMID: 23306967 DOI: 10.1007/s12013-012-9507-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
To propose a model for recently described amyloid aggregation of E.coli RNA polymerase σ(70) subunit, we have investigated the role of its N-terminal region. For this purpose, three mutant variants of protein with deletions Δ1-73, Δ1-100 and Δ74-100 were constructed and studied in a series of in vitro assays and using atomic force microscopy (AFM). Specifically, all RNA polymerase holoenzymes, reconstituted with the use of mutant σ subunits, have shown reduced affinity for promoter-containing DNA and reduced activity in run-off transcription experiments (compared to that of WT species), thus substantiating the modern concept on the modulatory role of N-terminus in formation of open complex and transcription initiation. The ability of mutant proteins to form amyloid-like structures has been investigated using AFM, which revealed the increased propensity of mutant proteins to form rodlike aggregates with the effect being more pronounced for the mutant with the deletion Δ1-73 (10 fold increase). σ(70) subunit aggregation ability has shown complex dependence on the ionic surrounding, which we explain by Debye screening effect and the change of the internal state of the protein. Basing on the obtained data, we propose the model of amyloid fibril formation by σ(70) subunit, implying the involvement of N-terminal region according to the domain swapping mechanism.
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Affiliation(s)
- Olga N Koroleva
- Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russian Federation
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Dubrovin EV, Popova AV, Kraevskiy SV, Ignatov SG, Ignatyuk TE, Yaminsky IV, Volozhantsev NV. Atomic force microscopy analysis of the Acinetobacter baumannii bacteriophage AP22 lytic cycle. PLoS One 2012; 7:e47348. [PMID: 23071792 PMCID: PMC3469531 DOI: 10.1371/journal.pone.0047348] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 09/11/2012] [Indexed: 11/21/2022] Open
Abstract
Background Acinetobacter baumannii is known for its ability to develop resistance to the major groups of antibiotics, form biofilms, and survive for long periods in hospital environments. The prevalence of infections caused by multidrug-resistant A. baumannii is a significant problem for the modern health care system, and application of lytic bacteriophages for controlling this pathogen may become a solution. Methodology/Principal Findings In this study, using atomic force microscopy (AFM) and microbiological assessment we have investigated A. baumannii bacteriophage AP22, which has been recently described. AFM has revealed the morphology of bacteriophage AP22, adsorbed on the surfaces of mica, graphite and host bacterial cells. Besides, morphological changes of bacteriophage AP22-infected A. baumannii cells were characterized at different stages of the lytic cycle, from phage adsorption to the cell lysis. The phage latent period, estimated from AFM was in good agreement with that obtained by microbiological methods (40 min). Bacteriophage AP22, whose head diameter is 62±1 nm and tail length is 88±9 nm, was shown to disperse A. baumannii aggregates and adsorb to the bacterial surface right from the first minute of their mutual incubation at 37°C. Conclusions/Significance High rate of bacteriophage AP22 specific adsorption and its ability to disperse bacterial aggregates make this phage very promising for biomedical antimicrobial applications. Complementing microbiological results with AFM data, we demonstrate an effective approach, which allows not only comparing independently obtained characteristics of the lytic cycle but also visualizing the infection process.
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Affiliation(s)
- Evgeniy V. Dubrovin
- M.V. Lomonosov Moscow State University, Moscow, Russian Federation
- Advanced Technologies Center, Moscow, Russian Federation
- * E-mail:
| | - Anastasia V. Popova
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Russian Federation
| | - Sergey V. Kraevskiy
- Alikhanov Institute for Theoretical and Experimental Physics, Moscow, Russian Federation
| | - Sergei G. Ignatov
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Russian Federation
| | - Tatyana E. Ignatyuk
- Alikhanov Institute for Theoretical and Experimental Physics, Moscow, Russian Federation
| | - Igor V. Yaminsky
- M.V. Lomonosov Moscow State University, Moscow, Russian Federation
- Advanced Technologies Center, Moscow, Russian Federation
| | - Nikolay V. Volozhantsev
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Russian Federation
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29
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Dubrovin EV, Fedyukina GN, Kraevsky SV, Ignatyuk TE, Yaminsky IV, Ignatov SG. AFM Specific Identification of Bacterial Cell Fragments on Biofunctional Surfaces. Open Microbiol J 2012; 6:22-8. [PMID: 22408697 PMCID: PMC3293165 DOI: 10.2174/1874285801206010022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 01/05/2012] [Accepted: 01/09/2012] [Indexed: 11/22/2022] Open
Abstract
Biointerfaces with a highly sensitive surface designed for specific interaction with biomolecules are essential approaches for providing advanced biochemical and biosensor assays. For the first time, we have introduced a simple AFM-based recognition system capable of visualizing specific bacterial nanofragments and identifying the corresponding bacterial type. For this we developed AFM-adjusted procedures for preparing IgG-based surfaces and subsequently exposing them to antigens. The AFM images reveal the specific binding of Escherichia coli cell fragments to the prepared biofunctional surfaces. Moreover, the binding of bacterial cell fragments to the affinity surfaces can be characterized quantitatively, indicating a 30-fold to 80-fold increase in the quantity of bound antigenic material in the case of a specific antigen-antibody pair. Our results demonstrate significant opportunities for developing reliable sensing procedures for detecting pathogenic bacteria, and the cell can still be identified after it is completely destroyed.
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Affiliation(s)
- Evgeniy V Dubrovin
- M.V. Lomonosov Moscow State University, 1/2 Leninskie gory, Moscow, 119991, Russia
| | - Galina N Fedyukina
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, 142279, Russia
| | - Sergey V Kraevsky
- Institute for Theoretical and Experimental Physics, 25 Bolshaya Cheremushkinskaya, Moscow, 117218, Russia
| | - Tatiana E Ignatyuk
- Institute for Theoretical and Experimental Physics, 25 Bolshaya Cheremushkinskaya, Moscow, 117218, Russia
| | - Igor V Yaminsky
- M.V. Lomonosov Moscow State University, 1/2 Leninskie gory, Moscow, 119991, Russia
| | - Sergei G Ignatov
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, 142279, Russia
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Arkhipenko MV, Petrova EK, Nikitin NA, Protopopova AD, Dubrovin EV, Yaminskii IV, Rodionova NP, Karpova OV, Atabekov JG. Characteristics of Artificial Virus-like Particles Assembled in vitro from Potato Virus X Coat Protein and Foreign Viral RNAs. Acta Naturae 2011. [DOI: 10.32607/20758251-2011-3-3-40-46] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Iaminskiĭ IV, Gorelkin PV, Dubrovin EV. [Nanoanalytics for medicine]. Biofizika 2011; 56:955-960. [PMID: 22117451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The applications of atomic force microscopy and the methods based on atomic force microscopy that can be useful in medical nanoanalytics have been reviewed. The main fields of possible application of scanning probe microscopy in medicine have been outlined. Among these are studying the resistance of bacterial cells to modern antibiotics and drugs, morphological analysis of blood components, trichology, nanotoxicology, DNA sequencing, and biocompatibility of medicinal materials. Examples of application of atomic force microscopy for studies in these fields have been considered, and prospects for its use in medicine have been demonstrated.
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Dubrovin EV, Koroleva ON, Khodak YA, Kuzmina NV, Yaminsky IV, Drutsa VL. AFM study of Escherichia coli RNA polymerase σ⁷⁰ subunit aggregation. Nanomedicine 2011; 8:54-62. [PMID: 21703992 DOI: 10.1016/j.nano.2011.05.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 05/20/2011] [Accepted: 05/21/2011] [Indexed: 10/18/2022]
Abstract
UNLABELLED The self-assembly of Escherichia coli RNA polymerase σ⁷⁰ subunit was investigated using several experimental approaches. A novel rodlike shape was reported for σ⁷⁰ subunit aggregates. Atomic force microscopy reveals that these aggregates, or σ⁷⁰ polymers, have a straight rodlike shape 5.4 nm in diameter and up to 300 nm in length. Atomic force microscopy data, Congo red binding assay, and sodium dodecyl sulfate gel electrophoresis confirm the amyloid nature of observed aggregates. The process of formation of rodlike structures proceeds spontaneously under nearly physiological conditions. E. coli RNA polymerase σ⁷⁰ subunit may be an interesting object for investigation of amyloidosis as well as for biotechnological applications that exploit self-assembled bionanostructures. Polymerization of σ⁷⁰ subunit may be a competitive process with its three-dimensional crystallization and association with core RNA polymerase. FROM THE CLINICAL EDITOR In this basic science study, the self-assembly of Escherichia coli RNA polymerase σ⁷⁰( subunit was investigated using atomic force microscopy and other complementary approaches.
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Affiliation(s)
- Evgeniy V Dubrovin
- Department of Physics of Polymers and Crystals, Faculty of Physics, Moscow State University, Russia.
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Efremov IM, Bagrov DV, Dubrovin EV, Bagrov DV, Dubrovin EV, Shaĭtan KV, Iaminskiĭ IV. [Atomic force microscopy of living cells: advances and future outlooks]. Biofizika 2011; 56:288-303. [PMID: 21542359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The advances of the method of atomic force microscopy for investigating the animal cells and an analysis of its development have been reviewed, with much attention being given to studies of living cells. The features and problems of the method have been considered, and a number of special methods based on the use of atomic force microscopy have been analyzed. The problems of choosing the geometry of probes for studies of animal cells, determination of cell adhesion on substrate, mapping of the cell surface using chemically modified cantilevers, and the distribution of molecular components inside the cell with the use of micro- and nanosurgical approaches have been discussed. The problems of combining the atomic force microscopy with optical and laser scanning confocal microscopy have been considered. Possible applications of the method in biotechnology and medicine are discussed.
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Dubrovin EV, Voloshin AG, Kraevsky SV, Ignatyuk TE, Abramchuk SS, Yaminsky IV, Ignatov SG. Atomic force microscopy investigation of phage infection of bacteria. Langmuir 2008; 24:13068-13074. [PMID: 18850726 DOI: 10.1021/la8022612] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Atomic force microscopy (AFM) was used to study the process of infection of bacterial cells by bacteriophages, for which purpose experimental protocols were elaborated. Three types of bacteriophages were characterized with AFM and transmission electron microscopy (TEM). Bacteriophage interaction with cells was studied for three bacterial hosts: Gram-negative Escherichia coli 057 and Salmonella enteritidis 89 and Gram-positive Bacillus thuringiensis 393. Depending on the phase of lytic cycle, different cell surface changes are observed in AFM images of infected cells in comparison with intact cells: from phage adsorption on the cells and flagella to complete lysis of the cells, accompanied by the release of a large number of newly formed phages. Control experiments (cells without phages and cells with nonspecific phages) did not reveal any surface changes. Penetration of phages inside obligate aerobe Bacillus thuringiensis was shown to be oxygen-dependent and required aeration in laboratory conditions. Our results show great potential of using AFM for numerous fundamental and applied tasks connected with pathogen-host interaction.
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Affiliation(s)
- Evgeniy V Dubrovin
- Department of Physics of Polymers and Crystals, Faculty of Physics, Moscow State University, Moscow, Russian Federation.
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Dubrovin EV, Staritsyn SN, Yakovenko SA, Yaminsky IV. Self-assembly effect during the adsorption of polynucleotides on stearic acid langmuir-blodgett monolayer. Biomacromolecules 2007; 8:2258-61. [PMID: 17583947 DOI: 10.1021/bm0702096] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Interaction of polyadenylic acid, poly(A), with stearic acid Langmuir-Blodgett (LB) monolayer was studied in different electrolyte surroundings. For this purpose LB films of stearic acid, transferred on the mica substrate from poly(A) containing subphase, were analyzed with atomic force microscopy (AFM). The density of polynucleotides surface coverage is ruled by the monovalent electrolyte concentration in the subphase that is in good agreement with previous results. Divalent cations in the subphase are needed to stabilize poly(A) molecules on the surface through formation of "salt bridges". At the very low divalent electrolyte concentration polynucleotides adsorb on the LB film to domains in which the effect of self-assembly is observed. Increase of divalent electrolyte concentration leads to the loss of this orientation effect. The explanation of this effect is proposed.
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Affiliation(s)
- Evgeniy V Dubrovin
- Department of Physics of Polymers and Crystals, Faculty of Physics, Moscow State University, Leninskie Gory, Moscow, Russia.
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Skabkin MA, Kiselyova OI, Chernov KG, Sorokin AV, Dubrovin EV, Yaminsky IV, Vasiliev VD, Ovchinnikov LP. Structural organization of mRNA complexes with major core mRNP protein YB-1. Nucleic Acids Res 2004; 32:5621-35. [PMID: 15494450 PMCID: PMC524299 DOI: 10.1093/nar/gkh889] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
YB-1 is a universal major protein of cytoplasmic mRNPs, a member of the family of multifunctional cold shock domain proteins (CSD proteins). Depending on its amount on mRNA, YB-1 stimulates or inhibits mRNA translation. In this study, we have analyzed complexes formed in vitro at various YB-1 to mRNA ratios, including those typical for polysomal (translatable) and free (untranslatable) mRNPs. We have shown that at mRNA saturation with YB-1, this protein alone is sufficient to form mRNPs with the protein/RNA ratio and the sedimentation coefficient typical for natural mRNPs. These complexes are dynamic structures in which the protein can easily migrate from one mRNA molecule to another. Biochemical studies combined with atomic force microscopy and electron microscopy showed that mRNA-YB-1 complexes with a low YB-1/mRNA ratio typical for polysomal mRNPs are incompact; there, YB-1 binds to mRNA as a monomer with its both RNA-binding domains. At a high YB-1/mRNA ratio typical for untranslatable mRNPs, mRNA-bound YB-1 forms multimeric protein complexes where YB-1 binds to mRNA predominantly with its N-terminal part. A multimeric YB-1 comprises about twenty monomeric subunits; its molecular mass is about 700 kDa, and it packs a 600-700 nt mRNA segment on its surface.
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Affiliation(s)
- Maxim A Skabkin
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
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Staritsyn SN, Mamashin VV, Zakharychev VV, Iaminskiĭ IV, Dubrovin EV, Lomonosov AM, Tverdislov VA, Iakovenko SA. [Mixed monolayers of amphiphile-modified nucleic bases and diynoic acids. I. Phase states at air-water interface and in Langmuir-Blodgett films]. Biofizika 2004; 49:635-45. [PMID: 15458246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Monolayers of amphiphile-modified nucleic bases with diynoic acid were obtained and characterized. The synthesized nucleic bases contained in the monolayer complementarily bind the nucleotide molecules contained in the aqueous subphase, and the structure of the resulting monolayers can be fixed by the photopolymerization of diynoic acid. The resulting monolayer exemplifies a novel type of model systems for investigating molecular recognition at the surface of biological membranes. Procedures for the transfer of the monolayers onto solid substrates and photopolymerization of the diynoic acid in mixtures with the derivatives of nucleic bases were developed. The films obtained were structurally characterized using atomic force microscopy. Compression isotherms of the mixed monolayers as well as individual components of monolayers at the air-water interface allowed one to determine the concentration range at which the diynoic acid form true mixtures or domain structures with the derivatives of nucleic base. A study of the films transferred to the solid substrate by atomic force microscopy indicated that this concentration dependence of miscibility behavior was conserved in the transferred films.
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