151
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Moses M, Hedegård P, Hatzakis N. Quantification of Functional Dynamics of Membrane Proteins Reconstituted in Nanodiscs Membranes by Single Turnover Functional Readout. Methods Enzymol 2016; 581:227-256. [DOI: 10.1016/bs.mie.2016.08.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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152
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Mechanics of Bacterial Cells and Initial Surface Colonisation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 915:245-60. [DOI: 10.1007/978-3-319-32189-9_15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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153
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Herman-Bausier P, Formosa-Dague C, Feuillie C, Valotteau C, Dufrêne YF. Forces guiding staphylococcal adhesion. J Struct Biol 2015; 197:65-69. [PMID: 26707623 DOI: 10.1016/j.jsb.2015.12.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 12/15/2015] [Accepted: 12/17/2015] [Indexed: 10/22/2022]
Abstract
Staphylococcus epidermidis and Staphylococcus aureus are two important nosocomial pathogens that form biofilms on indwelling medical devices. Biofilm infections are difficult to fight as cells within the biofilm show increased resistance to antibiotics. Our understanding of the molecular interactions driving bacterial adhesion, the first stage of biofilm formation, has long been hampered by the paucity of appropriate force-measuring techniques. In this minireview, we discuss how atomic force microscopy techniques have enabled to shed light on the molecular forces at play during staphylococcal adhesion. Specific highlights include the study of the binding mechanisms of adhesion molecules by means of single-molecule force spectroscopy, the measurement of the forces involved in whole cell interactions using single-cell force spectroscopy, and the probing of the nanobiophysical properties of living bacteria via multiparametric imaging. Collectively, these findings emphasize the notion that force and function are tightly connected in staphylococcal adhesion.
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Affiliation(s)
- Philippe Herman-Bausier
- Université catholique de Louvain, Institute of Life Sciences, Croix du Sud 4-5, bte L7.07.06, B-1348 Louvain-la-Neuve, Belgium
| | - Cécile Formosa-Dague
- Université catholique de Louvain, Institute of Life Sciences, Croix du Sud 4-5, bte L7.07.06, B-1348 Louvain-la-Neuve, Belgium
| | - Cécile Feuillie
- Université catholique de Louvain, Institute of Life Sciences, Croix du Sud 4-5, bte L7.07.06, B-1348 Louvain-la-Neuve, Belgium
| | - Claire Valotteau
- Université catholique de Louvain, Institute of Life Sciences, Croix du Sud 4-5, bte L7.07.06, B-1348 Louvain-la-Neuve, Belgium
| | - Yves F Dufrêne
- Université catholique de Louvain, Institute of Life Sciences, Croix du Sud 4-5, bte L7.07.06, B-1348 Louvain-la-Neuve, Belgium; Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Belgium.
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154
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Herman-Bausier P, Dufrêne YF. Atomic force microscopy reveals a dual collagen-binding activity for the staphylococcal surface protein SdrF. Mol Microbiol 2015; 99:611-21. [DOI: 10.1111/mmi.13254] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Philippe Herman-Bausier
- Institute of Life Sciences; Université catholique de Louvain; Croix du Sud, 1, bte L7.04.01. B-1348 Louvain-la-Neuve Belgium
| | - Yves F. Dufrêne
- Institute of Life Sciences; Université catholique de Louvain; Croix du Sud, 1, bte L7.04.01. B-1348 Louvain-la-Neuve Belgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO); Louvain-la-Neuve Belgium
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155
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Identifying and quantifying two ligand-binding sites while imaging native human membrane receptors by AFM. Nat Commun 2015; 6:8857. [PMID: 26561004 PMCID: PMC4660198 DOI: 10.1038/ncomms9857] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 10/11/2015] [Indexed: 01/29/2023] Open
Abstract
A current challenge in life sciences is to image cell membrane receptors while characterizing their specific interactions with various ligands. Addressing this issue has been hampered by the lack of suitable nanoscopic methods. Here we address this challenge and introduce multifunctional high-resolution atomic force microscopy (AFM) to image human protease-activated receptors (PAR1) in the functionally important lipid membrane and to simultaneously localize and quantify their binding to two different ligands. Therefore, we introduce the surface chemistry to bifunctionalize AFM tips with the native receptor-activating peptide and a tris-N-nitrilotriacetic acid (tris-NTA) group binding to a His10-tag engineered to PAR1. We further introduce ways to discern between the binding of both ligands to different receptor sites while imaging native PAR1s. Surface chemistry and nanoscopic method are applicable to a range of biological systems in vitro and in vivo and to concurrently detect and localize multiple ligand-binding sites at single receptor resolution.
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156
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Arnal L, Longo G, Stupar P, Castez MF, Cattelan N, Salvarezza RC, Yantorno OM, Kasas S, Vela ME. Localization of adhesins on the surface of a pathogenic bacterial envelope through atomic force microscopy. NANOSCALE 2015; 7:17563-17572. [PMID: 26446736 DOI: 10.1039/c5nr04644k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Bacterial adhesion is the first and a significant step in establishing infection. This adhesion normally occurs in the presence of flow of fluids. Therefore, bacterial adhesins must be able to provide high strength interactions with their target surface in order to maintain the adhered bacteria under hydromechanical stressing conditions. In the case of B. pertussis, a Gram-negative bacterium responsible for pertussis, a highly contagious human respiratory tract infection, an important protein participating in the adhesion process is a 220 kDa adhesin named filamentous haemagglutinin (FHA), an outer membrane and also secreted protein that contains recognition domains to adhere to ciliated respiratory epithelial cells and macrophages. In this work, we obtained information on the cell-surface localization and distribution of the B. pertussis adhesin FHA using an antibody-functionalized AFM tip. Through the analysis of specific molecular recognition events we built a map of the spatial distribution of the adhesin which revealed a non-homogeneous pattern. Moreover, our experiments showed a force induced reorganization of the adhesin on the surface of the cells, which could explain a reinforced adhesive response under external forces. This single-molecule information contributes to the understanding of basic molecular mechanisms used by bacterial pathogens to cause infectious disease and to gain insights into the structural features by which adhesins can act as force sensors under mechanical shear conditions.
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Affiliation(s)
- L Arnal
- Centro de Investigación y Desarrollo de Fermentaciones Industriales (CINDEFI-CONICET-CCT La Plata), Facultad de Ciencias Exactas, UNLP. 50 No 227, 1900 La Plata, Argentina
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157
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Cazaux S, Sadoun A, Biarnes-Pelicot M, Martinez M, Obeid S, Bongrand P, Limozin L, Puech PH. Synchronizing atomic force microscopy force mode and fluorescence microscopy in real time for immune cell stimulation and activation studies. Ultramicroscopy 2015; 160:168-181. [PMID: 26521163 DOI: 10.1016/j.ultramic.2015.10.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 09/17/2015] [Accepted: 10/12/2015] [Indexed: 11/24/2022]
Abstract
A method is presented for combining atomic force microscopy (AFM) force mode and fluorescence microscopy in order to (a) mechanically stimulate immune cells while recording the subsequent activation under the form of calcium pulses, and (b) observe the mechanical response of a cell upon photoactivation of a small G protein, namely Rac. Using commercial set-ups and a robust signal coupling the fluorescence excitation light and the cantilever bending, the applied force and activation signals were very easily synchronized. This approach allows to control the entire mechanical history of a single cell up to its activation and response down to a few hundreds of milliseconds, and can be extended with very minimal adaptations to other cellular systems where mechanotransduction is studied, using either purely mechanical stimuli or via a surface bound specific ligand.
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Affiliation(s)
- Séverine Cazaux
- Aix Marseille Université, LAI UM 61, Marseille F-13288, France; Inserm, UMR_S 1067, Marseille F-13288, France; CNRS, UMR 7333, Marseille F-13288, France
| | - Anaïs Sadoun
- Aix Marseille Université, LAI UM 61, Marseille F-13288, France; Inserm, UMR_S 1067, Marseille F-13288, France; CNRS, UMR 7333, Marseille F-13288, France
| | - Martine Biarnes-Pelicot
- Aix Marseille Université, LAI UM 61, Marseille F-13288, France; Inserm, UMR_S 1067, Marseille F-13288, France; CNRS, UMR 7333, Marseille F-13288, France
| | - Manuel Martinez
- Aix Marseille Université, LAI UM 61, Marseille F-13288, France; Inserm, UMR_S 1067, Marseille F-13288, France; CNRS, UMR 7333, Marseille F-13288, France
| | - Sameh Obeid
- Aix Marseille Université, LAI UM 61, Marseille F-13288, France; Inserm, UMR_S 1067, Marseille F-13288, France; CNRS, UMR 7333, Marseille F-13288, France
| | - Pierre Bongrand
- Aix Marseille Université, LAI UM 61, Marseille F-13288, France; Inserm, UMR_S 1067, Marseille F-13288, France; CNRS, UMR 7333, Marseille F-13288, France; APHM, Hôpital de la Conception, Laboratoire d'Immunologie, Marseille F-13385, France
| | - Laurent Limozin
- Aix Marseille Université, LAI UM 61, Marseille F-13288, France; Inserm, UMR_S 1067, Marseille F-13288, France; CNRS, UMR 7333, Marseille F-13288, France
| | - Pierre-Henri Puech
- Aix Marseille Université, LAI UM 61, Marseille F-13288, France; Inserm, UMR_S 1067, Marseille F-13288, France; CNRS, UMR 7333, Marseille F-13288, France.
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158
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Li M, Liu L, Xi N, Wang Y. Biological Applications of a Nanomanipulator Based on AFM: In situ visualization and quantification of cellular behaviors at the single-molecule level. IEEE NANOTECHNOLOGY MAGAZINE 2015. [DOI: 10.1109/mnano.2015.2441110] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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159
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Allenstein U, Mayr SG, Zink M. Contractile cell forces deform macroscopic cantilevers and quantify biomaterial performance. SOFT MATTER 2015; 11:5053-5059. [PMID: 26027952 DOI: 10.1039/c5sm01212k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Cells require adhesion to survive, proliferate and migrate, as well as for wound healing and many other functions. The strength of contractile cell forces on an underlying surface is a highly relevant quantity to measure the affinity of cells to a rigid surface with and without coating. Here we show with experimental and theoretical studies that these forces create surface stresses that are sufficient to induce measurable bending of macroscopic cantilevers. Since contractile forces are linked to the formation of focal contacts, results give information on adhesion promoting qualities and allow a comparison of very diverse materials. In exemplary studies, in vitro fibroblast adhesion on the magnetic shape memory alloy Fe-Pd and on the l-lysine derived plasma-functionalized polymer PPLL was determined. We show that cells on Fe-Pd are able to induce surface stresses three times as high as on pure titanium cantilevers. A further increase was observed for PPLL, where the contractile forces are four times higher than on the titanium reference. In addition, we performed finite element simulations on the beam bending to back up the calculation of contractile forces from cantilever bending under non-homogenous surface stress. Our findings consolidate the role of contractile forces as a meaningful measure of biomaterial performance.
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Affiliation(s)
- U Allenstein
- Leibniz Institute of Surface Modification (IOM) e.V., Permoserstr. 15, 04318 Leipzig, Germany.
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160
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Peralta-Yahya P. Biosensor keeps DOPA on track. Nat Chem Biol 2015; 11:450-1. [DOI: 10.1038/nchembio.1830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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161
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Nanoscale monitoring of drug actions on cell membrane using atomic force microscopy. Acta Pharmacol Sin 2015; 36:769-82. [PMID: 26027658 DOI: 10.1038/aps.2015.28] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Accepted: 03/13/2015] [Indexed: 02/06/2023] Open
Abstract
Knowledge of the nanoscale changes that take place in individual cells in response to a drug is useful for understanding the drug action. However, due to the lack of adequate techniques, such knowledge was scarce until the advent of atomic force microscopy (AFM), which is a multifunctional tool for investigating cellular behavior with nanometer resolution under near-physiological conditions. In the past decade, researchers have applied AFM to monitor the morphological and mechanical dynamics of individual cells following drug stimulation, yielding considerable novel insight into how the drug molecules affect an individual cell at the nanoscale. In this article we summarize the representative applications of AFM in characterization of drug actions on cell membrane, including topographic imaging, elasticity measurements, molecular interaction quantification, native membrane protein imaging and manipulation, etc. The challenges that are hampering the further development of AFM for studies of cellular activities are aslo discussed.
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162
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Dufrêne YF. Sticky microbes: forces in microbial cell adhesion. Trends Microbiol 2015; 23:376-82. [DOI: 10.1016/j.tim.2015.01.011] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 01/22/2015] [Accepted: 01/23/2015] [Indexed: 11/30/2022]
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163
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Guo C, Fan X, Qiu H, Xiao W, Wang L, Xu B. High-resolution probing heparan sulfate-antithrombin interaction on a single endothelial cell surface: single-molecule AFM studies. Phys Chem Chem Phys 2015; 17:13301-6. [PMID: 25921251 PMCID: PMC4431915 DOI: 10.1039/c5cp01305d] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Heparan sulfate (HS) plays diverse functions in multiple biological processes by interacting with a wide range of important protein ligands, such as the key anticoagulant factor, antithrombin (AT). The specific interaction of HS with a protein ligand is determined mainly by the sulfation patterns on the HS chain. Here, we reported the probing single-molecule interaction of AT and HS (both wild type and mutated) expressed on the endothelial cell surface under near-physiological conditions by atomic force microscopy (AFM). Functional AFM imaging revealed the uneven distribution of HS on the endothelial cell surface though they are highly expressed. Force spectroscopy measurements using an AT-functionalized AFM tip revealed that AT interacts with endothelial HS on the cell surface through multiple binding sites. The interaction essentially requires HS to be N-, 2-O- and/or 6-O-sulfated. This work provides a new tool to probe the HS-protein ligand interaction at a single-molecular level on the cell surface to elucidate the functional roles of HS.
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Affiliation(s)
- Cunlan Guo
- Single Molecule Study Laboratory, College of Engineering and Nanoscale Science and Engineering Center, University of Georgia, Athens, GA, USA.
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164
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165
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Wu Y, Sims RC, Zhou A. AFM resolves effects of ethambutol on nanomechanics and nanostructures of single dividing mycobacteria in real-time. Phys Chem Chem Phys 2015; 16:19156-64. [PMID: 24965038 DOI: 10.1039/c4cp01317d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Dynamic nanomechanics and nanostructures of dividing and anti-mycobacterial drug treated mycobacterium remain to be fully elucidated. Atomic force microscopy (AFM) is a promising nanotechnology tool for characterization of these dynamic alterations, especially at the single cell level. In this work, single dividing mycobacterium JLS (M.JLS) before and after anti-mycobacterial drug (ethambutol, EMB) treatment was in situ quantitatively analyzed, suggesting that nanomechanics would be referred as a sensitive indicator for evaluating efficacy of anti-mycobacterial drugs. Dynamic evidence on the contractile ring and septal furrow of dividing M.JLS implied that inhibition of contractile ring formation would be a crucial process for EMB to disturb M.JLS division. These results could facilitate further explaining the regulation mechanism of the contractile ring as well as nanomechanical roles of the cell wall in the course of mycobacterial division. This work describe a new way for further elucidating the mechanisms of mycobacterial division and anti-mycobacterial drug action, as well as the drug-resistance developing mechanism of pathogenic mycobacteria.
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Affiliation(s)
- Yangzhe Wu
- Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, Utah 84322-4105, USA.
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166
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Abstract
Atomic Force Microscopy relies on a nanoscale tip to image and probe samples, often down to the sub-nanometre level. The measurement process depends on the precise geometry and chemical nature of the tip apex, and is therefore difficult to control. In the current issue of Nanotechnology, Akrami and co-workers show that, for measurements in aqueous solutions and on flat samples, the presence of stable hydration sites at the tip apex is key to achieving high-resolution images. These sites can be created on commercial tips using a simple preparation strategy that prevents build-up of interfering contaminants. The findings by Akrami et al also suggest a possible way forward to control the influence of the tip on high-resolution measurements.
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167
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Long-tip high-speed atomic force microscopy for nanometer-scale imaging in live cells. Sci Rep 2015; 5:8724. [PMID: 25735540 PMCID: PMC4348644 DOI: 10.1038/srep08724] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/02/2015] [Indexed: 01/06/2023] Open
Abstract
Visualization of morphological dynamics of live cells with nanometer resolution under physiological conditions is highly desired, but challenging. It has been demonstrated that high-speed atomic force microscopy is a powerful technique for visualizing dynamics of biomolecules under physiological conditions. However, application of high-speed atomic force microscopy for imaging larger objects such as live mammalian cells has been complicated because of the collision between the cantilever and samples. Here, we demonstrate that attaching an extremely long (~3 μm) and thin (~5 nm) tip by amorphous carbon to the cantilever allows us to image the surface structure of live cells with the spatiotemporal resolution of nanometers and seconds. We demonstrate that long-tip high-speed atomic force microscopy is capable of imaging morphogenesis of filopodia, membrane ruffles, pit formation, and endocytosis in COS-7, HeLa cells and hippocampal neurons.
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168
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Aguayo S, Donos N, Spratt D, Bozec L. Single-bacterium nanomechanics in biomedicine: unravelling the dynamics of bacterial cells. NANOTECHNOLOGY 2015; 26:062001. [PMID: 25598514 DOI: 10.1088/0957-4484/26/6/062001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The use of the atomic force microscope (AFM) in microbiology has progressed significantly throughout the years since its first application as a high-resolution imaging instrument. Modern AFM setups are capable of characterizing the nanomechanical behaviour of bacterial cells at both the cellular and molecular levels, where elastic properties and adhesion forces of single bacterium cells can be examined under different experimental conditions. Considering that bacterial and biofilm-mediated infections continue to challenge the biomedical field, it is important to understand the biophysical events leading towards bacterial adhesion and colonization on both biological and non-biological substrates. The purpose of this review is to present the latest findings concerning the field of single-bacterium nanomechanics, and discuss future trends and applications of nanoindentation and single-cell force spectroscopy techniques in biomedicine.
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Affiliation(s)
- S Aguayo
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London, UK
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169
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El-Kirat-Chatel S, Beaussart A, Vincent SP, Flos MA, Hols P, Lipke PN, Dufrêne YF. Forces in yeast flocculation. NANOSCALE 2015; 7:1760-1767. [PMID: 25515338 PMCID: PMC4304900 DOI: 10.1039/c4nr06315e] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion ("flocculation") is conferred by a family of lectin-like proteins known as the flocculin (Flo) proteins. Knowledge of the adhesive and mechanical properties of flocculins is important for understanding the mechanisms of yeast adhesion, and may help controlling yeast behaviour in biotechnology. We use single-molecule and single-cell atomic force microscopy (AFM) to explore the nanoscale forces engaged in yeast flocculation, focusing on the role of Flo1 as a prototype of flocculins. Using AFM tips labelled with mannose, we detect single flocculins on Flo1-expressing cells, showing they are widely exposed on the cell surface. When subjected to force, individual Flo1 proteins display two distinct force responses, i.e. weak lectin binding forces and strong unfolding forces reflecting the force-induced extension of hydrophobic tandem repeats. We demonstrate that cell-cell adhesion bonds also involve multiple weak lectin interactions together with strong unfolding forces, both associated with Flo1 molecules. Single-molecule and single-cell data correlate with microscale cell adhesion behaviour, suggesting strongly that Flo1 mechanics is critical for yeast flocculation. These results favour a model in which not only weak lectin-sugar interactions are involved in yeast flocculation but also strong hydrophobic interactions resulting from protein unfolding.
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Affiliation(s)
- Sofiane El-Kirat-Chatel
- Université catholique de Louvain, Institute of Life Sciences, B-1348 Louvain-la-Neuve, Belgium
| | - Audrey Beaussart
- Université catholique de Louvain, Institute of Life Sciences, B-1348 Louvain-la-Neuve, Belgium
| | - Stéphane P. Vincent
- University of Namur, Department of Chemistry, Rue de Bruxelles 61, 5000 Namur, Belgium
| | - Marta Abellán Flos
- University of Namur, Department of Chemistry, Rue de Bruxelles 61, 5000 Namur, Belgium
| | - Pascal Hols
- Université catholique de Louvain, Institute of Life Sciences, B-1348 Louvain-la-Neuve, Belgium
| | - Peter N. Lipke
- Department of Biology, Brooklyn College of City University of New York, Brooklyn, New York 11210, USA
| | - Yves F. Dufrêne
- Université catholique de Louvain, Institute of Life Sciences, B-1348 Louvain-la-Neuve, Belgium
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170
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In PC3 prostate cancer cells ephrin receptors crosstalk to β1-integrins to strengthen adhesion to collagen type I. Sci Rep 2015; 5:8206. [PMID: 25644492 PMCID: PMC4314628 DOI: 10.1038/srep08206] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 01/13/2015] [Indexed: 02/08/2023] Open
Abstract
Eph receptor (Eph) and ephrin signaling can play central roles in prostate cancer and other cancer types. Exposed to ephrin-A1 PC3 prostate cancer cells alter adhesion to extracellular matrix (ECM) proteins. However, whether PC3 cells increase or reduce adhesion, and by which mechanisms they change adhesion to the ECM remains to be characterized. Here, we assay how ephrin-A1 stimulates PC3 cells to adhere to ECM proteins using single-cell force spectroscopy. We find that PC3 cells binding to immobilized ephrin-A1 but not to solubilized ephrin-A1 specifically strengthen adhesion to collagen I. This Eph-ephrin-A1 signaling, which we suppose is based on mechanotransduction, stimulates β1-subunit containing integrin adhesion via the protein kinase Akt and the guanine nucleotide-exchange factor cytohesin. Inhibiting the small GTPases, Rap1 or Rac1, generally lowered adhesion of PC3 prostate cancer cells. Our finding suggests a mechanism by which PC3 prostate cancer cells exposed to ephrins crosstalk to β1-integrins and preferably metastasize in bone, a collagen I rich tissue.
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171
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Yu M, Strohmeyer N, Wang J, Müller DJ, Helenius J. Increasing throughput of AFM-based single cell adhesion measurements through multisubstrate surfaces. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015; 6:157-66. [PMID: 25671160 PMCID: PMC4311671 DOI: 10.3762/bjnano.6.15] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/10/2014] [Indexed: 05/23/2023]
Abstract
Mammalian cells regulate adhesion by expressing and regulating a diverse array of cell adhesion molecules on their cell surfaces. Since different cell types express distinct sets of cell adhesion molecules, substrate-specific adhesion is cell type- and condition-dependent. Single-cell force spectroscopy is used to quantify the contribution of cell adhesion molecules to adhesion of cells to specific substrates at both the cell and single molecule level. However, the low throughput of single-cell adhesion experiments greatly limits the number of substrates that can be examined. In order to overcome this limitation, segmented polydimethylsiloxane (PDMS) masks were developed, allowing the measurement of cell adhesion to multiple substrates. To verify the utility of the masks, the adhesion of four different cell lines, HeLa (Kyoto), prostate cancer (PC), mouse kidney fibroblast and MDCK, to three extracellular matrix proteins, fibronectin, collagen I and laminin 332, was examined. The adhesion of each cell line to different matrix proteins was found to be distinct; no two cell lines adhered equally to each of the proteins. The PDMS masks improved the throughput limitation of single-cell force spectroscopy and allowed for experiments that previously were not feasible. Since the masks are economical and versatile, they can aid in the improvement of various assays.
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Affiliation(s)
- Miao Yu
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
- Center for Precision Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Nico Strohmeyer
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Jinghe Wang
- Center for Precision Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Daniel J Müller
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Jonne Helenius
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
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172
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Formosa C, Lachaize V, Galés C, Rols MP, Martin-Yken H, François JM, Duval RE, Dague E. Mapping HA-tagged protein at the surface of living cells by atomic force microscopy. J Mol Recognit 2014; 28:1-9. [DOI: 10.1002/jmr.2407] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 06/20/2014] [Accepted: 06/25/2014] [Indexed: 11/08/2022]
Affiliation(s)
- C. Formosa
- CNRS; LAAS; 7 avenue du Colonel Roche 31400 Toulouse France
- Université de Toulouse; LAAS, ITAV, IPBS; 31400 Toulouse France
- CNRS; UMR 7565, SRSMC; Vandœuvre-lès-Nancy France
- Université de Lorraine; UMR 7565, Faculté de Pharmacie; Nancy France
| | - V. Lachaize
- CNRS; LAAS; 7 avenue du Colonel Roche 31400 Toulouse France
- Université de Toulouse; LAAS, ITAV, IPBS; 31400 Toulouse France
- Institut des Maladies Métaboliques et Cardiovasculaires, Institut National de la Santé et de la Recherche Médicale U1048; Université Toulouse III Paul Sabatier; 31432 Toulouse France
- CNRS; ITAV; 1 Place Pierre Potier 31000 Toulouse France
| | - C. Galés
- Université de Toulouse; LAAS, ITAV, IPBS; 31400 Toulouse France
- Institut des Maladies Métaboliques et Cardiovasculaires, Institut National de la Santé et de la Recherche Médicale U1048; Université Toulouse III Paul Sabatier; 31432 Toulouse France
- CNRS; ITAV; 1 Place Pierre Potier 31000 Toulouse France
| | - M. P. Rols
- Université de Toulouse; LAAS, ITAV, IPBS; 31400 Toulouse France
- CNRS; IPBS, UMR 5089; 205 route de Narbonne 31077 Toulouse France
| | - H. Martin-Yken
- Université de Toulouse; LAAS, ITAV, IPBS; 31400 Toulouse France
- INRA; UMR 972 LISBP; Toulouse France
| | - J. M. François
- Université de Toulouse; LAAS, ITAV, IPBS; 31400 Toulouse France
- INRA; UMR 972 LISBP; Toulouse France
| | - R. E. Duval
- CNRS; UMR 7565, SRSMC; Vandœuvre-lès-Nancy France
- Université de Lorraine; UMR 7565, Faculté de Pharmacie; Nancy France
- ABC Platform®; Nancy France
| | - E. Dague
- CNRS; LAAS; 7 avenue du Colonel Roche 31400 Toulouse France
- Université de Toulouse; LAAS, ITAV, IPBS; 31400 Toulouse France
- CNRS; ITAV; 1 Place Pierre Potier 31000 Toulouse France
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173
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Bavishi K, Hatzakis NS. Shedding light on protein folding, structural and functional dynamics by single molecule studies. Molecules 2014; 19:19407-34. [PMID: 25429564 PMCID: PMC6272019 DOI: 10.3390/molecules191219407] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 11/07/2014] [Accepted: 11/12/2014] [Indexed: 11/16/2022] Open
Abstract
The advent of advanced single molecule measurements unveiled a great wealth of dynamic information revolutionizing our understanding of protein dynamics and behavior in ways unattainable by conventional bulk assays. Equipped with the ability to record distribution of behaviors rather than the mean property of a population, single molecule measurements offer observation and quantification of the abundance, lifetime and function of multiple protein states. They also permit the direct observation of the transient and rarely populated intermediates in the energy landscape that are typically averaged out in non-synchronized ensemble measurements. Single molecule studies have thus provided novel insights about how the dynamic sampling of the free energy landscape dictates all aspects of protein behavior; from its folding to function. Here we will survey some of the state of the art contributions in deciphering mechanisms that underlie protein folding, structural and functional dynamics by single molecule fluorescence microscopy techniques. We will discuss a few selected examples highlighting the power of the emerging techniques and finally discuss the future improvements and directions.
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Affiliation(s)
- Krutika Bavishi
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, Center for Synthetic Biology "bioSYNergy", Villum Research Center "Plant Plasticity", University of Copenhagen, Thorvaldsenvej 40, DK-1871 Frederiksberg C, Denmark.
| | - Nikos S Hatzakis
- Bio-Nanotechnology Laboratory, Department of Chemistry, Nano-Science Center, Lundbeck Foundation Center Biomembranes in Nanomedicine, University of Copenhagen, 2100 Copenhagen, Denmark.
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174
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Wang C, Yadavalli VK. Spatial recognition and mapping of proteins using DNA aptamers. NANOTECHNOLOGY 2014; 25:455101. [PMID: 25338629 DOI: 10.1088/0957-4484/25/45/455101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Atomic force microscopy-based adhesion force measurements have emerged as a powerful tool for the biophysical analyses of biological systems. Such measurements can now be extended to detection and mapping of biomolecules on surfaces via integrated imaging and force spectroscopy techniques. Critical to these experiments is the choice of the biomolecular recognition probe. In this study, we demonstrate how oligonucleotide aptamers can be used as versatile probes to simultaneously image and spatially locate targets on surfaces. We focus on two structurally distinct proteins relevant to the clotting cascade - human α-thrombin and vascular endothelial growth factor. Via AFM-recognition mapping using specific DNA aptamers on a commercially available instrument, we show a clear consistency between height and force measurements obtained simultaneously. Importantly, we are able to observe changes in binding due to changes in the external microenvironment, which demonstrate the ability to study fluctuating biological systems in real time. The aptamer specificity and the ability to distinguish their targets are shown through positive and negative controls. It is therefore possible to generate high resolution maps to spatially and temporally identify proteins at the molecular level on complex surfaces.
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175
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Andolfi L, Bourkoula E, Migliorini E, Palma A, Pucer A, Skrap M, Scoles G, Beltrami AP, Cesselli D, Lazzarino M. Investigation of adhesion and mechanical properties of human glioma cells by single cell force spectroscopy and atomic force microscopy. PLoS One 2014; 9:e112582. [PMID: 25390644 PMCID: PMC4229222 DOI: 10.1371/journal.pone.0112582] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 10/08/2014] [Indexed: 11/18/2022] Open
Abstract
Active cell migration and invasion is a peculiar feature of glioma that makes this tumor able to rapidly infiltrate into the surrounding brain tissue. In our recent work, we identified a novel class of glioma-associated-stem cells (defined as GASC for high-grade glioma -HG- and Gasc for low-grade glioma -LG-) that, although not tumorigenic, act supporting the biological aggressiveness of glioma-initiating stem cells (defined as GSC for HG and Gsc for LG) favoring also their motility. Migrating cancer cells undergo considerable molecular and cellular changes by remodeling their cytoskeleton and cell interactions with surrounding environment. To get a better understanding about the role of the glioma-associated-stem cells in tumor progression, cell deformability and interactions between glioma-initiating stem cells and glioma-associated-stem cells were investigated. Adhesion of HG/LG-cancer cells on HG/LG-glioma-associated stem cells was studied by time-lapse microscopy, while cell deformability and cell-cell adhesion strengths were quantified by indentation measurements by atomic force microscopy and single cell force spectroscopy. Our results demonstrate that for both HG and LG glioma, cancer-initiating-stem cells are softer than glioma-associated-stem cells, in agreement with their neoplastic features. The adhesion strength of GSC on GASC appears to be significantly lower than that observed for Gsc on Gasc. Whereas, GSC spread and firmly adhere on Gasc with an adhesion strength increased as compared to that obtained on GASC. These findings highlight that the grade of glioma-associated-stem cells plays an important role in modulating cancer cell adhesion, which could affect glioma cell migration, invasion and thus cancer aggressiveness. Moreover this work provides evidence about the importance of investigating cell adhesion and elasticity for new developments in disease diagnostics and therapeutics.
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Affiliation(s)
- Laura Andolfi
- Istituto Officina dei Materiali-National Research Council, Trieste, Italy
- * E-mail:
| | - Eugenia Bourkoula
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - Elisa Migliorini
- Département de Chimie Moléculaire, Ingénierie et Interactions Bio Moléculaires, Université Joseph Fourier, Grenoble, France
| | - Anita Palma
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - Anja Pucer
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - Miran Skrap
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - Giacinto Scoles
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | | | - Daniela Cesselli
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - Marco Lazzarino
- Istituto Officina dei Materiali-National Research Council, Trieste, Italy
- Cluster in Biomedicine, Trieste, Italy
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176
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Méndez-Méndez J, Alonso-Rasgado M, Correia Faria E, Flores-Johnson E, Snook R. Numerical study of the hydrodynamic drag force in atomic force microscopy measurements undertaken in fluids. Micron 2014; 66:37-46. [DOI: 10.1016/j.micron.2014.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 05/13/2014] [Accepted: 05/21/2014] [Indexed: 11/28/2022]
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177
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Otten M, Ott W, Jobst MA, Milles LF, Verdorfer T, Pippig DA, Nash MA, Gaub HE. From genes to protein mechanics on a chip. Nat Methods 2014; 11:1127-1130. [PMID: 25194847 PMCID: PMC4216144 DOI: 10.1038/nmeth.3099] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 07/29/2014] [Indexed: 01/28/2023]
Abstract
Single-molecule force spectroscopy enables mechanical testing of individual proteins, but low experimental throughput limits the ability to screen constructs in parallel. We describe a microfluidic platform for on-chip expression, covalent surface attachment and measurement of single-molecule protein mechanical properties. A dockerin tag on each protein molecule allowed us to perform thousands of pulling cycles using a single cohesin-modified cantilever. The ability to synthesize and mechanically probe protein libraries enables high-throughput mechanical phenotyping.
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Affiliation(s)
- Marcus Otten
- Lehrstuhl für Angewandte Physik, Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität, 80799 Munich, Germany
| | - Wolfgang Ott
- Lehrstuhl für Angewandte Physik, Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität, 80799 Munich, Germany
| | - Markus A Jobst
- Lehrstuhl für Angewandte Physik, Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität, 80799 Munich, Germany
| | - Lukas F Milles
- Lehrstuhl für Angewandte Physik, Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität, 80799 Munich, Germany
| | - Tobias Verdorfer
- Lehrstuhl für Angewandte Physik, Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität, 80799 Munich, Germany
| | - Diana A Pippig
- Lehrstuhl für Angewandte Physik, Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität, 80799 Munich, Germany
| | - Michael A Nash
- Lehrstuhl für Angewandte Physik, Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität, 80799 Munich, Germany
| | - Hermann E Gaub
- Lehrstuhl für Angewandte Physik, Ludwig-Maximilians-Universität, 80799 Munich, Germany
- Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität, 80799 Munich, Germany
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178
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Maciaszek JL, Partola K, Zhang J, Andemariam B, Lykotrafitis G. Single-cell force spectroscopy as a technique to quantify human red blood cell adhesion to subendothelial laminin. J Biomech 2014; 47:3855-61. [PMID: 25458578 DOI: 10.1016/j.jbiomech.2014.10.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 09/18/2014] [Accepted: 10/11/2014] [Indexed: 01/16/2023]
Abstract
Single-cell force spectroscopy (SCFS), an atomic force microscopy (AFM)-based assay, enables quantitative study of cell adhesion while maintaining the native state of surface receptors in physiological conditions. Human healthy and pathological red blood cells (RBCs) express a large number of surface proteins which mediate cell-cell interactions, or cell adhesion to the extracellular matrix. In particular, RBCs adhere with high affinity to subendothelial matrix laminin via the basal cell adhesion molecule and Lutheran protein (BCAM/Lu). Here, we established SCFS as an in vitro technique to study human RBC adhesion at baseline and following biochemical treatment. Using blood obtained from healthy human subjects, we recorded adhesion forces from single RBCs attached to AFM cantilevers as the cell was pulled-off of substrates coated with laminin protein. We found that an increase in the overall cell adhesion measured via SCFS is correlated with an increase in the resultant total force measured on 1 µm(2) areas of the RBC membrane. Further, we showed that SCFS can detect significant changes in the adhesive response of RBCs to modulation of the cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) pathway. Lastly, we identified variability in the RBC adhesion force to laminin amongst the human subjects, suggesting that RBCs maintain diverse levels of active BCAM/Lu adhesion receptors. By using single-cell measurements, we established a powerful new method for the quantitative measurement of single RBC adhesion with specific receptor-mediated binding.
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Affiliation(s)
- Jamie L Maciaszek
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA; Department of Hematology, Division of Experimental Hematology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Kostyantyn Partola
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA
| | - Jing Zhang
- Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA
| | - Biree Andemariam
- Adult Sickle Cell Disease Center, University of Connecticut Health Center, Farmington, CT, USA
| | - George Lykotrafitis
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA; Department of Mechanical Engineering, University of Connecticut, Storrs, CT, USA.
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179
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Cordova JC, Das DK, Manning HW, Lang MJ. Combining single-molecule manipulation and single-molecule detection. Curr Opin Struct Biol 2014; 28:142-8. [DOI: 10.1016/j.sbi.2014.08.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 07/24/2014] [Accepted: 08/12/2014] [Indexed: 11/24/2022]
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180
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Cell substratum adhesion during early development of Dictyostelium discoideum. PLoS One 2014; 9:e106574. [PMID: 25247557 PMCID: PMC4172474 DOI: 10.1371/journal.pone.0106574] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 07/31/2014] [Indexed: 11/30/2022] Open
Abstract
Vegetative and developed amoebae of Dictyostelium discoideum gain traction and move rapidly on a wide range of substrata without forming focal adhesions. We used two independent assays to quantify cell-substrate adhesion in mutants and in wild-type cells as a function of development. Using a microfluidic device that generates a range of hydrodynamic shear stress, we found that substratum adhesion decreases at least 10 fold during the first 6 hr of development of wild type cells. This result was confirmed using a single-cell assay in which cells were attached to the cantilever of an atomic force probe and allowed to adhere to untreated glass surfaces before being retracted. Both of these assays showed that the decrease in substratum adhesion was dependent on the cAMP receptor CAR1 which triggers development. Vegetative cells missing talin as the result of a mutation in talA exhibited slightly reduced adhesive properties compared to vegetative wild-type cells. In sharp contrast to wild-type cells, however, these talA mutant cells did not show further reduction of adhesion during development such that after 5 hr of development they were significantly more adhesive than developed wild type cells. In addition, both assays showed that substrate adhesion was reduced in 0 hr cells when the actin cytoskeleton was disrupted by latrunculin. Consistent with previous observations, substrate adhesion was also reduced in 0 hr cells lacking the membrane proteins SadA or SibA as the result of mutations in sadA or sibA. However, there was no difference in the adhesion properties between wild type AX3 cells and these mutant cells after 6 hr of development, suggesting that neither SibA nor SadA play an essential role in substratum adhesion during aggregation. Our results provide a quantitative framework for further studies of cell substratum adhesion in Dictyostelium.
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181
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Alford ST, Alpert MH. A synaptic mechanism for network synchrony. Front Cell Neurosci 2014; 8:290. [PMID: 25278839 PMCID: PMC4166887 DOI: 10.3389/fncel.2014.00290] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 08/31/2014] [Indexed: 01/06/2023] Open
Abstract
Within neural networks, synchronization of activity is dependent upon the synaptic connectivity of embedded microcircuits and the intrinsic membrane properties of their constituent neurons. Synaptic integration, dendritic Ca2+ signaling, and non-linear interactions are crucial cellular attributes that dictate single neuron computation, but their roles promoting synchrony and the generation of network oscillations are not well understood, especially within the context of a defined behavior. In this regard, the lamprey spinal central pattern generator (CPG) stands out as a well-characterized, conserved vertebrate model of a neural network (Smith et al., 2013a), which produces synchronized oscillations in which neural elements from the systems to cellular level that control rhythmic locomotion have been determined. We review the current evidence for the synaptic basis of oscillation generation with a particular emphasis on the linkage between synaptic communication and its cellular coupling to membrane processes that control oscillatory behavior of neurons within the locomotor network. We seek to relate dendritic function found in many vertebrate systems to the accessible lamprey central nervous system in which the relationship between neural network activity and behavior is well understood. This enables us to address how Ca2+ signaling in spinal neuron dendrites orchestrate oscillations that drive network behavior.
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Affiliation(s)
- Simon T Alford
- Department of Biological Sciences, University of Illinois at Chicago Chicago, IL, USA
| | - Michael H Alpert
- Department of Biological Sciences, University of Illinois at Chicago Chicago, IL, USA
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182
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Mashaghi A, Mashaghi S, Reviakine I, Heeren RMA, Sandoghdar V, Bonn M. Label-free characterization of biomembranes: from structure to dynamics. Chem Soc Rev 2014; 43:887-900. [PMID: 24253187 DOI: 10.1039/c3cs60243e] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We review recent progress in the study of the structure and dynamics of phospholipid membranes and associated proteins, using novel label-free analytical tools. We describe these techniques and illustrate them with examples highlighting current capabilities and limitations. Recent advances in applying such techniques to biological and model membranes for biophysical studies and biosensing applications are presented, and future prospects are discussed.
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Affiliation(s)
- Alireza Mashaghi
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
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183
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Liu N, Chen Y, Peng B, Lin Y, Wang Q, Su Z, Zhang W, Li H, Shen J. Single-molecule force spectroscopy study on the mechanism of RNA disassembly in tobacco mosaic virus. Biophys J 2014; 105:2790-800. [PMID: 24359751 DOI: 10.1016/j.bpj.2013.10.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 09/22/2013] [Accepted: 10/09/2013] [Indexed: 12/17/2022] Open
Abstract
To explore the disassembly mechanism of tobacco mosaic virus (TMV), a model system for virus study, during infection, we have used single-molecule force spectroscopy to mimic and follow the process of RNA disassembly from the protein coat of TMV by the replisome (molecular motor) in vivo, under different pH and Ca(2+) concentrations. Dynamic force spectroscopy revealed the unbinding free-energy landscapes as that at pH 4.7 the disassembly process is dominated by one free-energy barrier, whereas at pH 7.0 the process is dominated by one barrier and that there exists a second barrier. The additional free-energy barrier at longer distance has been attributed to the hindrance of disordered loops within the inner channel of TMV, and the biological function of those protein loops was discussed. The combination of pH increase and Ca(2+) concentration drop could weaken RNA-protein interactions so much that the molecular motor replisome would be able to pull and disassemble the rest of the genetic RNA from the protein coat in vivo. All these facts provide supporting evidence at the single-molecule level, to our knowledge for the first time, for the cotranslational disassembly mechanism during TMV infection under physiological conditions.
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Affiliation(s)
- Ningning Liu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China; School of Chemistry and Material Science, Liaoning Shihua University, Fushun, P. R. China
| | - Ying Chen
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China
| | - Bo Peng
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, P. R. China
| | - Yuan Lin
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, P. R. China
| | - Qian Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, P. R. China; Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina.
| | - Zhaohui Su
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, P. R. China
| | - Wenke Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China.
| | - Hongbin Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China; Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jiacong Shen
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China
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184
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Zhang S, Aslan H, Besenbacher F, Dong M. Quantitative biomolecular imaging by dynamic nanomechanical mapping. Chem Soc Rev 2014; 43:7412-29. [DOI: 10.1039/c4cs00176a] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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185
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Atomic force microscopy in microbiology: new structural and functional insights into the microbial cell surface. mBio 2014; 5:e01363-14. [PMID: 25053785 PMCID: PMC4120197 DOI: 10.1128/mbio.01363-14] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microbial cells sense and respond to their environment using their surface constituents. Therefore, understanding the assembly and biophysical properties of cell surface molecules is an important research topic. With its ability to observe living microbial cells at nanometer resolution and to manipulate single-cell surface molecules, atomic force microscopy (AFM) has emerged as a powerful tool in microbiology. Here, we survey major breakthroughs made in cell surface microbiology using AFM techniques, emphasizing the most recent structural and functional insights.
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186
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Li M, Xiao X, Zhang W, Liu L, Xi N, Wang Y. AFM analysis of the multiple types of molecular interactions involved in rituximab lymphoma therapy on patient tumor cells and NK cells. Cell Immunol 2014; 290:233-44. [PMID: 25117605 DOI: 10.1016/j.cellimm.2014.07.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 07/12/2014] [Accepted: 07/12/2014] [Indexed: 10/25/2022]
Abstract
Rituximab is a monoclonal antibody drug approved for the treatment of patients with lymphomas. Rituximab's main killing mechanism is antibody-dependent cellular cytotoxicity (ADCC). During ADCC, rituximab's fragment antigen binding (Fab) region binds to the CD20 antigen on the tumor cell and its fragment crystallizable (Fc) region binds to the Fc receptor (FcR) on the natural killer (NK) cells. In this study, two types of molecular interactions (CD20-rituximab, FcR-rituximab) involved in ADCC were measured simultaneously on cells prepared from biopsy specimens of lymphoma patients by utilizing atomic force microscopy (AFM) with functionalized tips carrying rituximab. NK cells were detected by specific NKp46 fluorescent labeling and tumor cells were detected by specific ROR1 fluorescent labeling. Based on the fluorescence recognition, the binding affinity and distribution of FcRs on NK cells, and CD20 on tumor cells, were quantitatively measured and mapped. The binding affinity and distribution of FcRs (on NK cells) and CD20 (on tumor cells) were associated with rituximab clinical efficacy. The experimental results provide a new approach to simultaneously quantify the multiple types of molecular interactions involved in rituximab ADCC mechanism on patient biopsy cells, which is of potential clinical significance to predict rituximab efficacy for personalized medicine.
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Affiliation(s)
- Mi Li
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiubin Xiao
- Department of Lymphoma, Affiliated Hospital of Military Medical Academy of Sciences, Beijing 100071, China
| | - Weijing Zhang
- Department of Lymphoma, Affiliated Hospital of Military Medical Academy of Sciences, Beijing 100071, China
| | - Lianqing Liu
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China.
| | - Ning Xi
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China; Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
| | - Yuechao Wang
- State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China
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187
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Costa L, Rodrigues MS, Benseny-Cases N, Mayeux V, Chevrier J, Comin F. Spectroscopic investigation of local mechanical impedance of living cells. PLoS One 2014; 9:e101687. [PMID: 24999625 PMCID: PMC4084948 DOI: 10.1371/journal.pone.0101687] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 06/10/2014] [Indexed: 11/29/2022] Open
Abstract
We studied nanoscale mechanical properties of PC12 living cells with a Force Feedback Microscope using two experimental approaches. The first one consists in measuring the local mechanical impedance of the cell membrane while simultaneously mapping the cell morphology at constant force. As the interaction force is increased, we observe the appearance of the sub-membrane cytoskeleton. We compare our findings with the outcome of other techniques. The second experimental approach consists in a spectroscopic investigation of the cell while varying the tip indentation into the membrane and consequently the applied force. At variance with conventional dynamic Atomic Force Microscopy techniques, here it is not mandatory to work at the first oscillation eigenmode of the cantilever: the excitation frequency of the tip can be chosen arbitrary leading then to new spectroscopic AFM techniques. We found in this way that the mechanical response of the PC12 cell membrane is found to be frequency dependent in the 1 kHz - 10 kHz range. In particular, we observe that the damping coefficient consistently decreases when the excitation frequency is increased.
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Affiliation(s)
- Luca Costa
- European Synchrotron Radiation Facility, Grenoble, France
- Université Joseph Fourier, Grenoble, France
- * E-mail:
| | - Mario S. Rodrigues
- Centro de Física da Matéria Condensada/Dep. Fisica, Faculdade de Ciência, Universidade de Lisboa, Lisboa, Portugal
| | - Núria Benseny-Cases
- Astbury Centre for Structural Molecular Biology, Leeds University, Leeds, United Kingdom
| | - Véronique Mayeux
- Astbury Centre for Structural Molecular Biology, Leeds University, Leeds, United Kingdom
| | - Joël Chevrier
- Centre National de la Recherche Scientifique, Institut NÉEL, Grenoble, France
- Université Grenoble Alpes, Institut NÉEL, Grenoble, France
| | - Fabio Comin
- European Synchrotron Radiation Facility, Grenoble, France
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188
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Herman P, El-Kirat-Chatel S, Beaussart A, Geoghegan JA, Foster TJ, Dufrêne YF. The binding force of the staphylococcal adhesin SdrG is remarkably strong. Mol Microbiol 2014; 93:356-68. [PMID: 24898289 DOI: 10.1111/mmi.12663] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2014] [Indexed: 11/27/2022]
Abstract
SdrG is a cell surface adhesin from Staphylococcus epidermidis which binds to the blood plasma protein fibrinogen (Fg). Ligand binding follows a 'dock, lock and latch' model involving dynamic conformational changes of the adhesin that result in a greatly stabilized adhesin-ligand complex. To date, the force and dynamics of this multistep interaction are poorly understood. Here we use atomic force microscopy (AFM) to unravel the binding strength and cell surface localization of SdrG at molecular resolution. Single-cell force spectroscopy shows that SdrG mediates time-dependent attachment to Fg-coated surfaces. Single-molecule force spectroscopy with Fg-coated AFM tips demonstrates that the adhesin forms nanoscale domains on the cell surface, which we believe contribute to strengthen cell adhesion. Notably, we find that the rupture force of single SdrG-Fg bonds is very large, ∼ 2 nN, equivalent to the strength of a covalent bond, and shows a low dissociation rate, suggesting that the bond is very stable. The strong binding force, slow dissociation and clustering of SdrG provide a molecular foundation for the ability of S. epidermidis to colonize implanted biomaterials and to withstand physiological shear forces.
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Affiliation(s)
- Philippe Herman
- Université catholique de Louvain, Institute of Life Sciences, Croix du Sud, 1, bte L7.04.01., B-1348, Louvain-la-Neuve, Belgium
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189
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Schubert R, Strohmeyer N, Bharadwaj M, Ramanathan SP, Krieg M, Friedrichs J, Franz CM, Muller DJ. Assay for characterizing the recovery of vertebrate cells for adhesion measurements by single-cell force spectroscopy. FEBS Lett 2014; 588:3639-48. [PMID: 24928443 DOI: 10.1016/j.febslet.2014.06.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 05/30/2014] [Accepted: 06/02/2014] [Indexed: 11/30/2022]
Abstract
Single-cell force spectroscopy (SCFS) is becoming a widely used method to quantify the adhesion of a living cell to a substrate, another cell or tissue. The high sensitivity of SCFS permits determining the contributions of individual cell adhesion molecules (CAMs) to the adhesion force of an entire cell. However, to prepare adherent cells for SCFS, they must first be detached from tissue-culture flasks or plates. EDTA and trypsin are often applied for this purpose. Because cellular properties can be affected by this treatment, cells need to recover before being further characterized by SCFS. Here we introduce atomic force microscopy (AFM)-based SCFS to measure the mechanical and adhesive properties of HeLa cells and mouse embryonic kidney fibroblasts while they are recovering after detachment from tissue-culture. We find that mechanical and adhesive properties of both cell lines recover quickly (<10 min) after detachment using EDTA, while trypsin-detached fibroblasts require >60 min to fully recover. Our assay introduced to characterize the recovery of mammalian cells after detachment can in future be used to estimate the recovery behavior of other adherent cell types.
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Affiliation(s)
- Rajib Schubert
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Nico Strohmeyer
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Mitasha Bharadwaj
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Subramanian P Ramanathan
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Michael Krieg
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA
| | - Jens Friedrichs
- Leibniz Institute of Polymer Research Dresden, Institute for Biofunctional Polymer Materials, Hohe Str. 6, 01069 Dresden, Germany
| | - Clemens M Franz
- Karlsruhe Institute of Technology (KIT), DFG-Center for Functional Nanostructures, Wolfgang-Gaede-Str. 1a, 76131 Karlsruhe, Germany
| | - Daniel J Muller
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland.
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190
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Bull MS, Sullan RMA, Li H, Perkins TT. Improved single molecule force spectroscopy using micromachined cantilevers. ACS NANO 2014; 8:4984-95. [PMID: 24670198 DOI: 10.1021/nn5010588] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Enhancing the short-term force precision of atomic force microscopy (AFM) while maintaining excellent long-term force stability would result in improved performance across multiple AFM modalities, including single molecule force spectroscopy (SMFS). SMFS is a powerful method to probe the nanometer-scale dynamics and energetics of biomolecules (DNA, RNA, and proteins). The folding and unfolding rates of such macromolecules are sensitive to sub-pN changes in force. Recently, we demonstrated sub-pN stability over a broad bandwidth (Δf = 0.01-16 Hz) by removing the gold coating from a 100 μm long cantilever. However, this stability came at the cost of increased short-term force noise, decreased temporal response, and poor sensitivity. Here, we avoided these compromises while retaining excellent force stability by modifying a short (L = 40 μm) cantilever with a focused ion beam. Our process led to a ∼10-fold reduction in both a cantilever's stiffness and its hydrodynamic drag near a surface. We also preserved the benefits of a highly reflective cantilever while mitigating gold-coating induced long-term drift. As a result, we extended AFM's sub-pN bandwidth by a factor of ∼50 to span five decades of bandwidth (Δf ≈ 0.01-1000 Hz). Measurements of mechanically stretching individual proteins showed improved force precision coupled with state-of-the-art force stability and no significant loss in temporal resolution compared to the stiffer, unmodified cantilever. Finally, these cantilevers were robust and were reused for SFMS over multiple days. Hence, we expect these responsive, yet stable, cantilevers to broadly benefit diverse AFM-based studies.
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Affiliation(s)
- Matthew S Bull
- JILA, National Institute of Standards and Technology and University of Colorado , Boulder, Colorado 80309, United States
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191
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Guillaume-Gentil O, Potthoff E, Ossola D, Franz CM, Zambelli T, Vorholt JA. Force-controlled manipulation of single cells: from AFM to FluidFM. Trends Biotechnol 2014; 32:381-8. [PMID: 24856959 DOI: 10.1016/j.tibtech.2014.04.008] [Citation(s) in RCA: 120] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 04/16/2014] [Accepted: 04/21/2014] [Indexed: 01/25/2023]
Abstract
The ability to perturb individual cells and to obtain information at the single-cell level is of central importance for addressing numerous biological questions. Atomic force microscopy (AFM) offers great potential for this prospering field. Traditionally used as an imaging tool, more recent developments have extended the variety of cell-manipulation protocols. Fluidic force microscopy (FluidFM) combines AFM with microfluidics via microchanneled cantilevers with nano-sized apertures. The crucial element of the technology is the connection of the hollow cantilevers to a pressure controller, allowing their operation in liquid as force-controlled nanopipettes under optical control. Proof-of-concept studies demonstrated a broad spectrum of single-cell applications including isolation, deposition, adhesion and injection in a range of biological systems.
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Affiliation(s)
| | - Eva Potthoff
- Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Dario Ossola
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, Gloriastrasse 35, 8092 Zurich, Switzerland
| | - Clemens M Franz
- DFG-Center for Functional Nanostructures, Karlsruhe Institute for Technology, Wolfgang-Gaede-Strasse 1a, 76131 Karlsruhe, Germany
| | - Tomaso Zambelli
- Laboratory of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, Gloriastrasse 35, 8092 Zurich, Switzerland.
| | - Julia A Vorholt
- Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland.
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192
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Lamprecht C, Hinterdorfer P, Ebner A. Applications of biosensing atomic force microscopy in monitoring drug and nanoparticle delivery. Expert Opin Drug Deliv 2014; 11:1237-53. [PMID: 24809228 DOI: 10.1517/17425247.2014.917078] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION The therapeutic effects of medicinal drugs not only depend on their properties, but also on effective transport to the target receptor. Here we highlight recent developments in this discipline and show applications of atomic force microscopy (AFM) that enable us to track the effects of drugs and the effectiveness of nanoparticle delivery at the single molecule level. AREAS COVERED Physiological AFM imaging enables visualization of topographical changes to cells as a result of drug exposure and allows observation of cellular responses that yield morphological changes. When we upgrade the regular measuring tip to a molecular biosensor, it enables investigation of functional changes at the molecular level via single molecule force spectroscopy. EXPERT OPINION Biosensing AFM techniques have generated powerful tools to monitor drug delivery in (living) cells. While technical developments in actual AFM methods have simplified measurements at relevant physiological conditions, understanding both the biological and technical background is still a crucial factor. However, due to its potential impact, we expect the number of application-based biosensing AFM techniques to further increase in the near future.
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Affiliation(s)
- Constanze Lamprecht
- University of Kiel, Institute of Materials Science Biocompatible Nanomaterials , Kaiserstr.2, 24143 Kiel , Germany
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193
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Ultrastable atomic force microscopy: improved force and positional stability. FEBS Lett 2014; 588:3621-30. [PMID: 24801176 DOI: 10.1016/j.febslet.2014.04.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 04/18/2014] [Accepted: 04/23/2014] [Indexed: 11/20/2022]
Abstract
Atomic force microscopy (AFM) is an exciting technique for biophysical studies of single molecules, but its usefulness is limited by instrumental drift. We dramatically reduced positional drift by adding two lasers to track and thereby actively stabilize the tip and the surface. These lasers also enabled label-free optical images that were spatially aligned to the tip position. Finally, sub-pN force stability over 100 s was achieved by removing the gold coating from soft cantilevers. These enhancements to AFM instrumentation can immediately benefit research in biophysics and nanoscience.
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194
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Pfreundschuh M, Martinez-Martin D, Mulvihill E, Wegmann S, Muller DJ. Multiparametric high-resolution imaging of native proteins by force-distance curve–based AFM. Nat Protoc 2014; 9:1113-30. [DOI: 10.1038/nprot.2014.070] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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195
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Beaussart A, El-Kirat-Chatel S, Sullan RMA, Alsteens D, Herman P, Derclaye S, Dufrêne YF. Quantifying the forces guiding microbial cell adhesion using single-cell force spectroscopy. Nat Protoc 2014; 9:1049-55. [DOI: 10.1038/nprot.2014.066] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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196
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Ando T, Uchihashi T, Scheuring S. Filming biomolecular processes by high-speed atomic force microscopy. Chem Rev 2014; 114:3120-88. [PMID: 24476364 PMCID: PMC4076042 DOI: 10.1021/cr4003837] [Citation(s) in RCA: 234] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Indexed: 12/21/2022]
Affiliation(s)
- Toshio Ando
- Department of Physics, and Bio-AFM Frontier
Research Center, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
- CREST,
Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Takayuki Uchihashi
- Department of Physics, and Bio-AFM Frontier
Research Center, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
- CREST,
Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Simon Scheuring
- U1006
INSERM/Aix-Marseille Université, Parc Scientifique et Technologique
de Luminy Bâtiment Inserm TPR2 bloc 5, 163 avenue de Luminy, 13288 Marseille Cedex 9, France
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197
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Tudor C, te Riet J, Eich C, Harkes R, Smisdom N, Bouhuijzen Wenger J, Ameloot M, Holt M, Kanger JS, Figdor CG, Cambi A, Subramaniam V. Syntenin-1 and ezrin proteins link activated leukocyte cell adhesion molecule to the actin cytoskeleton. J Biol Chem 2014; 289:13445-60. [PMID: 24662291 DOI: 10.1074/jbc.m113.546754] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Activated leukocyte cell adhesion molecule (ALCAM) is a type I transmembrane protein member of the immunoglobulin superfamily of cell adhesion molecules. Involved in important pathophysiological processes such as the immune response, cancer metastasis, and neuronal development, ALCAM undergoes both homotypic interactions with other ALCAM molecules and heterotypic interactions with the surface receptor CD6 expressed at the T cell surface. Despite biochemical and biophysical evidence of a dynamic association between ALCAM and the actin cytoskeleton, no detailed information is available about how this association occurs at the molecular level. Here, we exploit a combination of complementary microscopy techniques, including FRET detected by fluorescence lifetime imaging microscopy and single-cell force spectroscopy, and we demonstrate the existence of a preformed ligand-independent supramolecular complex where ALCAM stably interacts with actin by binding to syntenin-1 and ezrin. Interaction with the ligand CD6 further enhances these multiple interactions. Altogether, our results propose a novel biophysical framework to understand the stabilizing role of the ALCAM supramolecular complex engaged to CD6 during dendritic cell-T cell interactions and provide novel information on the molecular players involved in the formation and signaling of the immunological synapse at the dendritic cell side.
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Affiliation(s)
- Cicerone Tudor
- From the Nanobiophysics, MIRA Institute for Biomedical Technology and Technical Medicine and MESA+ Institute for Nanotechnology, University of Twente, 7500AE Enschede, The Netherlands
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198
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Xie H, Yin M, Rong W, Sun L. In situ quantification of living cell adhesion forces: single cell force spectroscopy with a nanotweezer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:2952-2959. [PMID: 24571680 DOI: 10.1021/la500045q] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A novel method is presented for in situ quantification of living cell adhesion forces using a homemade nanorobotic system provided with two independently actuated probes that form a dual-probe nanotweezer capable of pick-and-place manipulation of a single living cell in an aqueous environment. Compared with single-cell force spectroscopy (SCFS) based on traditional atomic force microscopy (AFM), cell immobilization via chemical trapping is unnecessary and the test cell can be efficiently released using the nanotweezer to significantly enhance production of the SCFS. Benefiting from the accurate force sensing capability of AFM, the nanotweezer allows reliable force measurement ranging from picoNewtons to microNewtons and is sufficiently sensitive to characterize short- and long-term adhesion of cell-cell and cell-substrate adhesions. Capabilities of the nanotweezer have been validated through experimental qualification of cell-substrate and cell-cell adhesion events of C2C12 cells (mouse myoblast adherent) with different contact times.
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Affiliation(s)
- Hui Xie
- The State Key Laboratory of Robotics and Systems, Harbin Institute of Technology , 2 Yikuang, C1 HIT Science Park, 150080 Harbin, China
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199
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Xing Y, Li A, Felker DL, Burggraf LW. Nanoscale structural and mechanical analysis of Bacillus anthracis spores inactivated with rapid dry heating. Appl Environ Microbiol 2014; 80:1739-49. [PMID: 24375142 PMCID: PMC3957622 DOI: 10.1128/aem.03483-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 12/21/2013] [Indexed: 11/20/2022] Open
Abstract
Effective killing of Bacillus anthracis spores is of paramount importance to antibioterrorism, food safety, environmental protection, and the medical device industry. Thus, a deeper understanding of the mechanisms of spore resistance and inactivation is highly desired for developing new strategies or improving the known methods for spore destruction. Previous studies have shown that spore inactivation mechanisms differ considerably depending upon the killing agents, such as heat (wet heat, dry heat), UV, ionizing radiation, and chemicals. It is believed that wet heat kills spores by inactivating critical enzymes, while dry heat kills spores by damaging their DNA. Many studies have focused on the biochemical aspects of spore inactivation by dry heat; few have investigated structural damages and changes in spore mechanical properties. In this study, we have inactivated Bacillus anthracis spores with rapid dry heating and performed nanoscale topographical and mechanical analysis of inactivated spores using atomic force microscopy (AFM). Our results revealed significant changes in spore morphology and nanomechanical properties after heat inactivation. In addition, we also found that these changes were different under different heating conditions that produced similar inactivation probabilities (high temperature for short exposure time versus low temperature for long exposure time). We attributed the differences to the differential thermal and mechanical stresses in the spore. The buildup of internal thermal and mechanical stresses may become prominent only in ultrafast, high-temperature heat inactivation when the experimental timescale is too short for heat-generated vapor to efficiently escape from the spore. Our results thus provide direct, visual evidences of the importance of thermal stresses and heat and mass transfer to spore inactivation by very rapid dry heating.
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Affiliation(s)
- Yun Xing
- Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base (WPAFB), Dayton, Ohio, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, Tennessee, USA
| | - Alex Li
- Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base (WPAFB), Dayton, Ohio, USA
| | - Daniel L. Felker
- Department of Systems Engineering & Management, Air Force Institute of Technology, WPAFB, Dayton, Ohio, USA
| | - Larry W. Burggraf
- Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base (WPAFB), Dayton, Ohio, USA
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200
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El-Kirat-Chatel S, Beaussart A, Boyd CD, O’Toole GA, Dufrêne YF. Single-cell and single-molecule analysis deciphers the localization, adhesion, and mechanics of the biofilm adhesin LapA. ACS Chem Biol 2014; 9:485-94. [PMID: 24556201 DOI: 10.1021/cb400794e] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The large adhesin protein LapA mediates adhesion and biofilm formation by Pseudomonas fluorescens. Although adhesion is thought to involve the long multiple repeats of LapA, very little is known about the molecular mechanism by which this protein mediates attachment. Here we use atomic force microscopy to unravel the biophysical properties driving LapA-mediated adhesion. Single-cell force spectroscopy shows that expression of LapA on the cell surface via biofilm-inducing conditions (i.e., phosphate-rich medium) or deletion of the gene encoding the LapG protease (LapA+ mutant) increases the adhesion strength of P. fluorescens toward hydrophobic and hydrophilic substrates, consistent with the adherent phenotypes observed in these conditions. Substrate chemistry plays an unexpected role in modulating the mechanical response of LapA, with sequential unfolding of the multiple repeats occurring only on hydrophilic substrates. Biofilm induction also leads to shortening of the protein extensions, reflecting stiffening of their conformational properties. Using single-molecule force spectroscopy, we next demonstrate that the adhesin is randomly distributed on the surface of wild-type cells and can be released into the solution. For LapA+ mutant cells, we found that the adhesin massively accumulates on the cell surface without being released and that individual LapA repeats unfold when subjected to force. The remarkable adhesive and mechanical properties of LapA provide a molecular basis for the "multi-purpose" adhesion function of LapA, thereby making P. fluorescens capable of colonizing diverse environments.
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Affiliation(s)
- Sofiane El-Kirat-Chatel
- Institute
of Life Sciences, Université catholique de Louvain, Croix du
Sud, 1, bte L7.04.01, B-1348 Louvain-la-Neuve, Belgium
| | - Audrey Beaussart
- Institute
of Life Sciences, Université catholique de Louvain, Croix du
Sud, 1, bte L7.04.01, B-1348 Louvain-la-Neuve, Belgium
| | - Chelsea D. Boyd
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
| | - George A. O’Toole
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
| | - Yves F. Dufrêne
- Institute
of Life Sciences, Université catholique de Louvain, Croix du
Sud, 1, bte L7.04.01, B-1348 Louvain-la-Neuve, Belgium
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