Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Two-chamber AFM: probing membrane proteins separating two aqueous compartments

Abstract

Biological membranes compartmentalize and define physical borders of cells. They are crowded with membrane proteins that fulfill diverse crucial functions. About one-third of all genes in organisms code for, and the majority of drugs target, membrane proteins. To combine structure and function analysis of membrane proteins, we designed a two-chamber atomic force microscopy (AFM) setup that allows investigation of membranes spanned over nanowells, therefore separating two aqueous chambers. We imaged nonsupported surface layers (S layers) of Corynebacterium glutamicum at sufficient resolution to delineate a 15 Å–wide protein pore. We probed the elastic and yield moduli of nonsupported membranes, giving access to the lateral interaction energy between proteins. We combined AFM and fluorescence microscopy to demonstrate the functionality of proteins in the setup by documenting proton pumping by Halobacterium salinarium purple membranes.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Membrane adsorption on holey Si(001) surfaces.
Figure 2: High-resolution imaging of nonsupported membranes.
Figure 3: Membrane piercing.
Figure 4: Proton pumping of nonsupported purple membranes.

Similar content being viewed by others

References

  1. Neher, E. & Sakmann, B. Single-channel currents recorded from membrane of denervated frog muscle fibres. Nature 260, 799–802 (1976).

    Article  CAS  Google Scholar 

  2. Mueller, P., Rudin, D.O., Tien, H.T. & Wescott, W.C. Reconstitution of cell membrane structure in vitro and its transformation into an excitable system. Nature 194, 979–980 (1962).

    Article  CAS  Google Scholar 

  3. Huang, C. Studies on phosphatidylcholine vesicles. Formation and physical characteristics. Biochemistry 8, 344–352 (1969).

    Article  CAS  Google Scholar 

  4. Caffrey, M. Membrane protein crystallization. J. Struct. Biol. 142, 108–132 (2003).

    Article  CAS  Google Scholar 

  5. Fujiyoshi, Y. The structural study of membrane proteins by electron crystallography. Adv. Biophys. 35, 25–80 (1998).

    Article  CAS  Google Scholar 

  6. Frank, J. Single-particle imaging of macromolecules by cryo-electron microscopy. Annu. Rev. Biophys. Biomol. Struct. 31, 303–319 (2002).

    Article  CAS  Google Scholar 

  7. Binnig, G., Quate, C.F. & Gerber, C. Atomic force microscope. Phys. Rev. Lett. 56, 930–933 (1986).

    Article  CAS  Google Scholar 

  8. Müller, D.J., Fotiadis, D., Scheuring, S., Müller, S.A. & Engel, A. Electrostatically balanced subnanometer imaging of biological specimens by atomic force microscopy. Biophys. J. 76, 1101–1111 (1999).

    Article  Google Scholar 

  9. Schabert, F.A., Henn, C. & Engel, A. Native Escherichia coli OmpF porin surfaces probed by atomic force microscopy. Science 268, 92–94 (1995).

    Article  CAS  Google Scholar 

  10. Fotiadis, D. et al. Atomic-force microscopy: Rhodopsin dimers in native disc membranes. Nature 421, 127–128 (2003).

    Article  CAS  Google Scholar 

  11. Scheuring, S. & Sturgis, J.N. Chromatic adaptation of photosynthetic membranes. Science 309, 484–487 (2005).

    Article  CAS  Google Scholar 

  12. Oesterhelt, D. & Stoeckenius, W. Functions of a new photoreceptor membrane. Proc. Natl. Acad. Sci. USA 70, 2853–2857 (1973).

    Article  CAS  Google Scholar 

  13. Danelon, C., Perez, J.P., Santschi, C., Brugger, J. & Vogel, H. Cell membranes suspended across nanoaperture arrays. Langmuir 22, 22–25 (2006).

    Article  CAS  Google Scholar 

  14. Chami, M. et al. Organization of the outer layers of the cell envelope of Corynebacterium glutamicum: A combined freeze-etch electron microscopy and biochemical study. Biol. Cell 83, 219–229 (1995).

    Article  CAS  Google Scholar 

  15. Scheuring, S. et al. Charting and unzipping the surface-layer of Corynebacterium glutamicum with the atomic force microscope. Mol. Microbiol. 44, 675–684 (2002).

    Article  CAS  Google Scholar 

  16. Sleytr, U.B. Basic and applied S-layer research: an overview. FEMS Microbiol. Rev. 20, 5–12 (1997).

    Article  CAS  Google Scholar 

  17. Scheuring, S., Levy, D. & Rigaud, J-L. Watching the components of photosynthetic bacterial membranes and their “in situ” organization by atomic force microscopy. Biochim. Biophys. Acta 1712, 109–127 (2005).

    Article  CAS  Google Scholar 

  18. Chang, G., Spencer, R.H., Lee, A.T., Barclay, M.T. & Rees, D.C. Structure of the MscL homolog from Mycobacterium tuberculosis: a gated mechanosensitive ion channel. Science 282, 2220–2226 (1998).

    Article  CAS  Google Scholar 

  19. Landau, L.D. & Lifschitz, E.M. Theory of elasticity (Pergamon Press, New York, 1986).

    Google Scholar 

  20. Yao, X., Jericho, M.H., Pink, D. & Beveridge, T.J. Thickness and elasticity of gram-negative murein sacculi measured by atomic force microscopy. J. Bacteriol. 181, 6865–6875 (1999).

    CAS  Google Scholar 

  21. Evans, E. & Rawics, W. Entropy-driven tension and bending elasticity in condensed-fluid membranes. Phys. Rev. Lett. 64, 2094–2097 (1990).

    Article  CAS  Google Scholar 

  22. Kano, K. & Fendler, J.H. Pyranine as a sensitive pH probe for liposome interiors and surfaces. pH gradients across phospholipid vesicles. Biochim. Biophys. Acta 509, 289–299 (1978).

    Article  CAS  Google Scholar 

  23. Seigneuret, M. & Rigaud, J.L. Use of fluorescent pH probe pyranine to detect heterogeneous directions of proton movement in bacteriorhodopsin reconsituted large liposomes. FEBS Lett. 188, 101–106 (1985).

    Article  CAS  Google Scholar 

  24. Stock, D., Leslie, A.G. & Walker, J.E. Molecular architecture of the rotary motor in ATP synthase. Science 286, 1700–1705 (1999).

    Article  CAS  Google Scholar 

  25. Oesterhelt, F. et al. Unfolding pathways of individual bacteriorhodopsins. Science 288, 143–146 (2000).

    Article  CAS  Google Scholar 

  26. Müller, D.J. et al. Observing membrane protein diffusion at subnanometer resolution. J. Mol. Biol. 327, 925–930 (2003).

    Article  Google Scholar 

  27. Stahlberg, H. et al. Two-dimensional crystals: a powerful approach to assess structure, function and dynamics of membrane proteins. FEBS Lett. 504, 166–172 (2001).

    Article  CAS  Google Scholar 

  28. Viani, M.B. et al. Probing protein-protein interactions in real time. Nat. Struct. Biol. 7, 644–647 (2000).

    Article  CAS  Google Scholar 

  29. Seifert, U. Dynamics of a bound membrane. Phys. Rev. E Stat. Phys. Plasmas Fluids Relat. Interdiscip. Topics 49, 3124–3127 (1994).

    CAS  Google Scholar 

  30. Sorzano, C.O. et al. XMIPP: a new generation of an open-source image processing package for electron microscopy. J. Struct. Biol. 148, 194–204 (2004).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank F. Oesterhelt for assistance in force curve analysis, A. Martinez-Gil for technical assistance, C. Gueudry for help with fluorescence microscopy and S. Lesko for spring-constant determination. This study was supported by the INSERM and INSERM Avenir, a 'Ministère de l'Education Nationale' scholarship (to R.P.G.) and an Action Concertée Incitative Nanosciences 2004 grant (NR206).

Author information

Authors and Affiliations

Authors

Contributions

R.P.G. performed AFM imaging, S-layer preparation with C.H., fluorescence imaging and fluorescence data analysis. G.A. and B.B. prepared the nanopatterned Si(001) surfaces. P.S. and S.S. performed force-curve analysis and physical interpretation. S.S performed image and data analysis, conceived the project and prepared the manuscript.

Corresponding author

Correspondence to Simon Scheuring.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Fig. 1

Schematic representation of the 2-chamber AFM setup. (PDF 663 kb)

Supplementary Fig. 2

AFM characterization of the holey Si(001) support wafers. (PDF 1512 kb)

Supplementary Video 1

Proton pumping of non-supported purple membranes. Sequence of green fluorescence images over a time-range of 500 seconds documenting fluorescence intensity variations in chambers. (MOV 467 kb)

Supplementary Note

Digital image treatment (PDF 48 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Gonçalves, R., Agnus, G., Sens, P. et al. Two-chamber AFM: probing membrane proteins separating two aqueous compartments. Nat Methods 3, 1007–1012 (2006). https://doi.org/10.1038/nmeth965

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nmeth965

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing