Abstract
Over the past years, atomic force microscopy (AFM) has emerged as a powerful tool for imaging the surface of microbial cells with nanometer resolution, and under physiological conditions. Moreover, chemical force microscopy (CFM) and single-molecule force spectroscopy have enabled researchers to map chemical groups and receptors on cell surfaces, providing valuable insight into their structure–function relationships. Here, we present protocols for analyzing spores of the pathogen Aspergillus fumigatus using real-time AFM imaging and CFM. We emphasize the use of porous polymer membranes for immobilizing single live cells, and the modification of gold-coated tips with alkanethiols for CFM measurements. We also discuss recording conditions and data interpretation, and provide recommendations for reliable experiments. For well-trained AFM users, the entire protocol can be completed in 2–3 d.
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Acknowledgements
The author dedicates this article to the memory of Terry J. Beveridge, pioneering expert in electron and atomic force microscopies, and thanks his colleagues and collaborators for sharing exciting experiments and discussions. This work was supported by the National Foundation for Scientific Research (FNRS), the Université Catholique de Louvain (Fonds Spéciaux de Recherche), the Région wallonne, the Federal Office for Scientific, Technical and Cultural Affairs (Interuniversity Poles of Attraction Programme), and the Research Department of the Communauté française de Belgique (Concerted Research Action). Y.F.D. is a Research Associate of the FNRS.
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Dufrêne, Y. Atomic force microscopy and chemical force microscopy of microbial cells. Nat Protoc 3, 1132–1138 (2008). https://doi.org/10.1038/nprot.2008.101
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DOI: https://doi.org/10.1038/nprot.2008.101
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