Structural and Mechanical Characterization of Viruses with AFM

  • Álvaro Ortega-Esteban
  • Natália Martín-González
  • Francisco Moreno-Madrid
  • Aida Llauró
  • Mercedes Hernando-Pérez
  • Cármen San MartÚn
  • Pedro J. de PabloEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1886)


Microscopes are used to characterize small objects with the help of probes that interact with the specimen, such as photons and electrons in optical and electron microscopies, respectively. In atomic force microscopy (AFM) the probe is a nanometric tip located at the end of a micro cantilever which palpates the specimen under study as a blind person manages a walking stick. In this way AFM allows obtaining nanometric resolution images of individual protein shells, such as viruses, in liquid milieu. Beyond imaging, AFM also enables not only the manipulation of single protein cages, but also the characterization of every physicochemical property able of inducing any measurable mechanical perturbation to the microcantilever that holds the tip. In this chapter we start revising some recipes for adsorbing protein shells on surfaces. Then we describe several AFM approaches to study individual protein cages, ranging from imaging to spectroscopic methodologies devoted for extracting physical information, such as mechanical and electrostatic properties. We also explain how a convenient combination of AFM and fluorescence methodologies entails monitoring genome release from individual viral shells during mechanical unpacking.

Key words

Atomic force microscopy Force curve Nanoindentation Beam deflection Tip Cantilever Stylus Topography Aqueous solution Disruption Breaking Fatigue Electrostatics 



We acknowledge our collaborators and projects FIS2017-89549-R, Fundación BBVA and “María de Maeztu” Program for Units of Excellence in R&D (MDM-2014-0377).


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Álvaro Ortega-Esteban
    • 1
  • Natália Martín-González
    • 2
  • Francisco Moreno-Madrid
    • 2
  • Aida Llauró
    • 3
  • Mercedes Hernando-Pérez
    • 1
  • Cármen San MartÚn
    • 1
  • Pedro J. de Pablo
    • 2
    • 4
    Email author
  1. 1.Department of Structure of MacromoleculesCentro Nacional de Biotecnología (CNB–CSIC)MadridSpain
  2. 2.Departamento de Física de la Materia CondensadaUniversidad Autónoma de MadridMadridSpain
  3. 3.School of MedicineUniversity of WashingtonSeattleUSA
  4. 4.Solid Condensed Matter Institute IFIMAC, Universidad Autónoma de MadridMadridSpain

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