- Physical Review Journals
All JournalsPhysics Magazine
Access Provided by Xinjiang University

Physical Review E

Export citation

Export citation

Choose format for download:

Download Citation
  • Access by Xinjiang University

β-connectin studies by small-angle x-ray scattering and single-molecule force spectroscopy by atomic force microscopy

S. Marchetti1, F. Sbrana2, A. Toscano3, E. Fratini4, M. Carlà1, M. Vassalli2, B. Tiribilli5, A. Pacini3, and C. M. C. Gambi1

  • 1Department of Physics, University of Florence and CNISM Via G. Sansone 1, IT-50019, Sesto Fiorentino (Florence), Italy
  • 2Biophysics Institute of the National Research Council, Via De Marini 6, Genova, Italy
  • 3Department of Anatomy, Histology, and Forensic Medicine, University of Florence, Florence, Italy
  • 4Department of Chemistry and Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase (CSGI), University of Florence, Via della Lastruccia 3, IT-50019, Sesto Fiorentino (Florence), Italy
  • 5Complex System Institute of the National Research Council (ISC-CNR), Sesto Fiorentino (Florence), Italy

PDF

Phys. Rev. E 83, 051919 – Published 24 May, 2011

DOI: https://doi.org/10.1103/PhysRevE.83.051919

Abstract

The three-dimensional structure and the mechanical properties of a β-connectin fragment from human cardiac muscle, belonging to the I band, from I27 to I34, were investigated by small-angle x-ray scattering (SAXS) and single-molecule force spectroscopy (SMFS). This molecule presents an entropic elasticity behavior, associated to globular domain unfolding, that has been widely studied in the last 10 years. In addition, atomic force microscopy based SMFS experiments suggest that this molecule has an additional elastic regime, for low forces, probably associated to tertiary structure remodeling. From a structural point of view, this behavior is a mark of the fact that the eight domains in the I27-I34 fragment are not independent and they organize in solution, assuming a well-defined three-dimensional structure. This hypothesis has been confirmed by SAXS scattering, both on a diluted and a concentrated sample. Two different models were used to fit the SAXS curves: one assuming a globular shape and one corresponding to an elongated conformation, both coupled with a Coulomb repulsion potential to take into account the protein-protein interaction. Due to the predominance of the structure factor, the effective shape of the protein in solution could not be clearly disclosed. By performing SMFS by atomic force microscopy, mechanical unfolding properties were investigated. Typical sawtooth profiles were obtained and the rupture force of each unfolding domain was estimated. By fitting a wormlike chain model to each peak of the sawtooth profile, the entropic elasticity of octamer was described.

    View figure in article

      Article Text

      References (36)

      1. K. Maruyama, Int. Rev. Cytol. 104, 81 (1986).
      2. H. Higuchi, Y. Nakauchi, K. Maruyama, and S. Fujme, Biophys. J. 65, 1906 (1993).
      3. L. Tskhovrebova and J. Trinick, Nat. Rev. Mol. Cell Biol. 4, 679 (2003).
      4. S. Improta, A. S. Politou, and A. Pastore, Structure 4, 323 (1996).
      5. S. Labeit and B. Kolmerer, Science 270, 293 (1995).
      6. E. von Castelmur, M. Marino, D. I. Svergun, L. Kreplak, Z. Ucurum-Fotiadis, P. V. Konarev, A. Urzhumtsev, D. Labeit, S. Labeit, and O. Mayans, Proc. Natl. Acad. Sci. USA. 105, 1186 (2008).
      7. E. H. Lee, J. Hsin, E. von Castelmur, O. Mayans, and K. Schulten, Biophys. J. 98, 1085 (2010); J. Hsin and K. Schulten, ibid. 100, L22 (2011).
      8. M. Rief, M. Gautel, F. Oesterhelt, J. M. Fernandez, and H. E. Gaub, Science 276, 1109 (1997).
      9. A. Imparato, F. Sbrana, and M. Vassalli, Europhys. Lett. 82, 58006 (2008).
      10. S. Marchetti, F. Sbrana, R. Raccis, L. Lanzi, C. M. C. Gambi, M. Vassalli, B. Tiribilli, A. Pacini, and A. Toscano, Phys. Rev. E 77, 021910 (2008).
      11. S. C. Gill and P. H. von Hippel, Anal. Biochem. 182, 319 (1989).
      12. [http://www.scripps.edu/cdputnam/protcalc.html].
      13. E. Mylonas and D. I. Svergun, J. Appl. Crystallogr. 40, s245 (2007).
      14. T. N. Blanton, T. C. Huang, H. Toraya, C. R. Hubbard, S. B. Robie, D. Louer, H. E. Gobel, G. Will, R. Gilles, and T. Raftery, Powder Diffraction 10, 91 (1995).
      15. J. A. Lake, Acta Crystallogr. 23, 191 (1967).
      16. C. Bustamante, S. B. Smith, J. Liphardt, and D. Smith, Curr. Opin. Struct. Biol. 10, 279 (2000).
      17. S. H. Chen and E. Y. Sheu, in Micellar Solutions and Microemulsions: Structure, Dynamics, and Statistical Thermodynamics, edited by S. H. Chen (Springer, New York, 1990).
      18. S. H. Chen, E. Y. Sheu, J. Kalus, and H. Hoffmann, J. Appl. Crystallogr. 21, 751 (1988).
      19. P. Baglioni, E. Fratini, B. Lonetti, and S. H. Chen, J. Phys. Condens. Matter 16, S5003 (2004).
      20. B. Lonetti, E. Fratini, S. H. Chen, and P. Baglioni, Phys. Chem. Chem. Phys. 6, 1338 (2004).
      21. A. Guinier and G. Fournet, Small-Angle Scattering of X-Rays (Wiley, New York, 1955).
      22. O. Glatter and O. Kratky, Small Angle X-Ray Scattering (Academic, New York, 1982).
      23. M. Kotlarchyk and S. H. Chen, J. Chem. Phys. 79, 241 (1983).
      24. L. Scaffei, L. Lanzi, C. M. C. Gambi, R. Giordano, P. Baglioni, and J. Teixeira, J. Phys. Chem. B 106, 10771 (2002).
      25. C. M. C. Gambi, R. Giordano, M. Laurati, L. Lanzi, F. Pini, and P. Baglioni, Appl. Phys. A: Mater. Sci. Process. 74, s377 (2002).
      26. R. Nossal, C. J. Glinka, and S. H. Chen, Biopolymers 25, 1157 (1986).
      27. S. H. Chen, Annu. Rev. Phys. Chem. 37, 351 (1986).
      28. S. Khan, T. L. Morton, and D. Ronis, Phys. Rev. A 35, 4295 (1987).
      29. J. P. Hansen and J. B. Hayter, Mol. Phys. 46, 651 (1982).
      30. R. J. Hunter, Foundations of Colloid Science (Clarendon Press, Oxford, 1987), Vol. I.
      31. S. Improta, J. K. Krueger, M. Gautel, R. A. Atkinson, J. F. Lefevre, S. Moulton, J. Trewhella, and A. Pastore, J. Mol. Biol. 284, 761 (1998).
      32. M. Marino, D. I. Svergun, L. Kreplak, P. V. Konarev, B. Maco, D. Labeit, and O. Mayans, J. Muscle Res. Cell Motil. 26, 355 (2005).
      33. W. R. Chen, P. D. Butler, and L. J. Magid, Langmuir 22, 6539 (2006).
      34. S. R. Kline, J. Appl. Crystallogr. 39, 895 (2006).
      35. C. F. Wu and S. H. Chen, Biopolymers 27, 1065 (1988).
      36. D. I. Svergun, S. Richard, M. H. J. Koch, Z. Sayers, S. Kuprin, and G. Zaccai, Proc. Natl. Acad. Sci. USA. 95, 2267 (1998).

      Outline

      Information

      Phys. Rev. E 83, 051919– Published 24 May, 2011
      • Received 27 July 2010

      ©2011 American Physical Society

      Sign In to Your Journals Account

      Filter

      Filter

      Article Lookup

      Enter a citation