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:

Automated identification of functional dynamic contact networks from X-ray crystallography

Abstract

Protein function often depends on the exchange between conformational substates. Allosteric ligand binding or distal mutations can stabilize specific active-site conformations and consequently alter protein function. Observing alternative conformations at low levels of electron density, in addition to comparison of independently determined X-ray crystal structures, can provide mechanistic insights into conformational dynamics. Here we report a new algorithm, CONTACT, that identifies contact networks of conformationally heterogeneous residues directly from high-resolution X-ray crystallography data. Contact networks determined for Escherichia coli dihydrofolate reductase (ecDHFR) predict the observed long-range pattern of NMR chemical shift perturbations of an allosteric mutation. A comparison of contact networks in wild-type and mutant ecDHFR suggests that mutations that alter optimized contact networks of coordinated motions can impair catalytic function. CONTACT-guided mutagenesis can exploit the structure-dynamics-function relationship in protein engineering and design.

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: Mechanisms for conformational exchange in cyclophilin A.
Figure 2: Characteristics of pathways and contact networks are sensitive to temperature.
Figure 3: All-atom contact networks in ecDHFR.
Figure 4: Contact-network analysis and an allosteric mutant (G121V) of ecDHFR.
Figure 5: Increased conformational heterogeneity at the active site of the crystal structure of the E:NADP+:FOL complex of the N23PP/S148A mutant.

Similar content being viewed by others

Accession codes

Primary accessions

Protein Data Bank

Referenced accessions

Protein Data Bank

References

  1. Fraser, J.S. & Jackson, C.J. Mining electron density for functionally relevant protein polysterism in crystal structures. Cell. Mol. Life Sci. 68, 1829–1841 (2011).

    Article  CAS  Google Scholar 

  2. Karplus, M. & Kuriyan, J. Molecular dynamics and protein function. Proc. Natl. Acad. Sci. USA 102, 6679–6685 (2005).

    Article  CAS  Google Scholar 

  3. Marlow, M.S., Dogan, J., Frederick, K.K., Valentine, K.G. & Wand, A.J. The role of conformational entropy in molecular recognition by calmodulin. Nat. Chem. Biol. 6, 352–358 (2010).

    Article  CAS  Google Scholar 

  4. Fraser, J.S. et al. Hidden alternative structures of proline isomerase essential for catalysis. Nature 462, 669–673 (2009).

    Article  CAS  Google Scholar 

  5. Yu, B. et al. Structural and energetic mechanisms of cooperative autoinhibition and activation of Vav1. Cell 140, 246–256 (2010).

    Article  CAS  Google Scholar 

  6. Fraser, J.S. et al. Accessing protein conformational ensembles using room-temperature X-ray crystallography. Proc. Natl. Acad. Sci. USA 108, 16247–16252 (2011).

    Article  CAS  Google Scholar 

  7. Whitten, S.T., García-Moreno, E.B. & Hilser, V.J. Local conformational fluctuations can modulate the coupling between proton binding and global structural transitions in proteins. Proc. Natl. Acad. Sci. USA 102, 4282–4287 (2005).

    Article  CAS  Google Scholar 

  8. Mittermaier, A.K. & Kay, L.E. Observing biological dynamics at atomic resolution using NMR. Trends Biochem. Sci. 34, 601–611 (2009).

    Article  CAS  Google Scholar 

  9. Goodey, N.M. & Benkovic, S.J. Allosteric regulation and catalysis emerge via a common route. Nat. Chem. Biol. 4, 474–482 (2008).

    Article  CAS  Google Scholar 

  10. Kern, D. & Zuiderweg, E.R. The role of dynamics in allosteric regulation. Curr. Opin. Struct. Biol. 13, 748–757 (2003).

    Article  CAS  Google Scholar 

  11. Burling, F. & Brünger, A. Thermal motion and conformational disorder in protein crystal structures: comparison of multi-conformer and time-averaging models. Isr. J. Chem. 34, 165–175 (1994).

    Article  CAS  Google Scholar 

  12. Levin, E.J., Kondrashov, D.A., Wesenberg, G.E. & Phillips, G.N. Jr. Ensemble refinement of protein crystal structures. Structure 15, 1040–1052 (2007).

    Article  CAS  Google Scholar 

  13. Knight, J.L. et al. Exploring structural variability in X-ray crystallographic models using protein local optimization by torsion-angle sampling. Acta Crystallogr. D Biol. Crystallogr. 64, 383–396 (2008).

    Article  CAS  Google Scholar 

  14. Kuriyan, J. et al. Exploration of disorder in protein structures by X-ray restrained molecular dynamics. Proteins 10, 340–358 (1991).

    Article  CAS  Google Scholar 

  15. Terwilliger, T.C. et al. Interpretation of ensembles created by multiple iterative rebuilding of macromolecular models. Acta Crystallogr. D Biol. Crystallogr. 63, 597–610 (2007).

    Article  CAS  Google Scholar 

  16. Wilson, M.A. & Brunger, A.T. The 1.0 Å crystal structure of Ca2+-bound calmodulin: an analysis of disorder and implications for functionally relevant plasticity. J. Mol. Biol. 301, 1237–1256 (2000).

    Article  CAS  Google Scholar 

  17. Rader, S.D. & Agard, D.A. Conformational substates in enzyme mechanism: the 120K structure of α-lytic protease at 1.5 Å resolution. Protein Sci. 6, 1375–1386 (1997).

    Article  CAS  Google Scholar 

  18. Burnley, B.T., Afonine, P.V., Adams, P.D. & Gros, P. Modelling dynamics in protein crystal structures by ensemble refinement. eLife 1, e00311 (2012).

    Article  Google Scholar 

  19. van den Bedem, H., Dhanik, A., Latombe, J.-C. & Deacon, A.M. Modeling discrete heterogeneity in X-ray diffraction data by fitting multi-conformers. Acta Crystallogr. D Biol. Crystallogr. 65, 1107–1117 (2009).

    Article  CAS  Google Scholar 

  20. Lang, P.T. et al. Automated electron-density sampling reveals widespread conformational polymorphism in proteins. Protein Sci. 19, 1420–1431 (2010).

    Article  CAS  Google Scholar 

  21. Lindorff-Larsen, K., Best, R.B., Depristo, M.A., Dobson, C.M. & Vendruscolo, M. Simultaneous determination of protein structure and dynamics. Nature 433, 128–132 (2005).

    Article  CAS  Google Scholar 

  22. Serrano, P. et al. Comparison of NMR and crystal structures highlights conformational isomerism in protein active sites. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 66, 1393–1405 (2010).

    Article  CAS  Google Scholar 

  23. Young, M.A., Gonfloni, S., Superti-Furga, G., Roux, B. & Kuriyan, J. Dynamic coupling between the SH2 and SH3 domains of c-Src and Hck underlies their inactivation by C-terminal tyrosine phosphorylation. Cell 105, 115–126 (2001).

    Article  CAS  Google Scholar 

  24. Halabi, N., Rivoire, O., Leibler, S. & Ranganathan, R. Protein sectors: evolutionary units of three-dimensional structure. Cell 138, 774–786 (2009).

    Article  CAS  Google Scholar 

  25. McClendon, C.L., Friedland, G., Mobley, D.L., Amirkhani, H. & Jacobson, M.P. Quantifying correlations between allosteric sites in thermodynamic ensembles. J. Chem. Theory Comput. 5, 2486–2502 (2009).

    Article  CAS  Google Scholar 

  26. DuBay, K.H., Bothma, J.P. & Geissler, P.L. Long-range intra-protein communication can be transmitted by correlated side-chain fluctuations alone. PLoS Comput. Biol. 7, e1002168 (2011).

    Article  CAS  Google Scholar 

  27. Kidd, B.A., Baker, D. & Thomas, W.E. Computation of conformational coupling in allosteric proteins. PLoS Comput. Biol. 5, e1000484 (2009).

    Article  Google Scholar 

  28. Eisenmesser, E.Z. et al. Intrinsic dynamics of an enzyme underlies catalysis. Nature 438, 117–121 (2005).

    Article  CAS  Google Scholar 

  29. Schlegel, J., Armstrong, G.S., Redzic, J.S., Zhang, F. & Eisenmesser, E.Z. Characterizing and controlling the inherent dynamics of cyclophilin-A. Protein Sci. 18, 811–824 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  30. Boehr, D.D., McElheny, D., Dyson, H.J. & Wright, P.E. The dynamic energy landscape of dihydrofolate reductase catalysis. Science 313, 1638–1642 (2006).

    Article  CAS  Google Scholar 

  31. Sawaya, M.R. & Kraut, J. Loop and subdomain movements in the mechanism of Escherichia coli dihydrofolate reductase: crystallographic evidence. Biochemistry 36, 586–603 (1997).

    Article  CAS  Google Scholar 

  32. Boehr, D.D. et al. A distal mutation perturbs dynamic amino acid networks in dihydrofolate reductase. Biochemistry 52, 4605–4619 (2013).

    Article  CAS  Google Scholar 

  33. Cameron, C.E. & Benkovic, S.J. Evidence for a functional role of the dynamics of glycine-121 of Escherichia coli dihydrofolate reductase obtained from kinetic analysis of a site-directed mutant. Biochemistry 36, 15792–15800 (1997).

    Article  CAS  Google Scholar 

  34. Rod, T.H., Radkiewicz, J.L. & Brooks, C.L. Correlated motion and the effect of distal mutations in dihydrofolate reductase. Proc. Natl. Acad. Sci. USA 100, 6980–6985 (2003).

    Article  CAS  Google Scholar 

  35. Mauldin, R.V., Sapienza, P.J., Petit, C.M. & Lee, A.L. Structure and dynamics of the G121V dihydrofolate reductase mutant: lessons from a transition-state inhibitor complex. PLoS ONE 7, e33252 (2012).

    Article  CAS  Google Scholar 

  36. Bhabha, G. et al. A dynamic knockout reveals that conformational fluctuations influence the chemical step of enzyme catalysis. Science 332, 234–238 (2011).

    Article  CAS  Google Scholar 

  37. Boutet, S. et al. High-resolution protein structure determination by serial femtosecond crystallography. Science 337, 362–364 (2012).

    Article  CAS  Google Scholar 

  38. Halle, B. Biomolecular cryocrystallography: structural changes during flash-cooling. Proc. Natl. Acad. Sci. USA 101, 4793–4798 (2004).

    Article  CAS  Google Scholar 

  39. Zhuravlev, P.I. & Papoian, G.A. Protein functional landscapes, dynamics, allostery: a tortuous path towards a universal theoretical framework. Q. Rev. Biophys. 43, 295–332 (2010).

    Article  CAS  Google Scholar 

  40. Khersonsky, O. et al. Optimization of the in-silico-designed kemp eliminase KE70 by computational design and directed evolution. J. Mol. Biol. 407, 391–412 (2011).

    Article  CAS  Google Scholar 

  41. Brünger, A.T. Free R value: a novel statistical quantity for assessing the accuracy of crystal structures. Nature 355, 472–475 (1992).

    Article  Google Scholar 

  42. Dror, R.O., Dirks, R.M., Grossman, J.P., Xu, H. & Shaw, D.E. Biomolecular simulation: a computational microscope for molecular biology. Annu. Rev. Biophys. 41, 429–452 (2012).

    Article  CAS  Google Scholar 

  43. Adams, P.D. et al. PHENIX: a comprehensive Python-based system for macromolecular structure solution. Acta Crystallogr. D Biol. Crystallogr. 66, 213–221 (2010).

    Article  CAS  Google Scholar 

  44. Osborne, M.J., Schnell, J., Benkovic, S.J., Dyson, H.J. & Wright, P.E. Backbone dynamics in dihydrofolate reductase complexes: role of loop flexibility in the catalytic mechanism. Biochemistry 40, 9846–9859 (2001).

    Article  CAS  Google Scholar 

  45. Falzone, C.J. et al. 1H, 15N and 13C resonance assignments, secondary structure, and the conformation of substrate in the binary folate complex of Escherichia coli dihydrofolate reductase. J. Biomol. NMR 4, 349–366 (1994).

    Article  CAS  Google Scholar 

  46. Winter, G., Lobley, C.M.C. & Prince, S.M. Decision making in xia2. Acta Crystallogr. D Biol. Crystallogr. 69, 1260–1273 (2013).

    Article  CAS  Google Scholar 

  47. Kabsch, W. XDS. Acta Crystallogr. D Biol. Crystallogr. 66, 125–132 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

  48. McCoy, A.J. et al. Phaser crystallographic software. J. Appl. Crystallogr. 40, 658–674 (2007).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

H.v.d.B. is supported by the US National Institute of General Medical Sciences Protein Structure Initiative (U54GM094586) at the Joint Center for Structural Genomics and SLAC National Accelerator Laboratory LDRD (Laboratory Directed Research and Development) grant SLAC-LDRD-0014-13-2; G.B. is supported as a Merck Fellow of the Damon Runyon Cancer Research Foundation (DRG-2136-12); K.Y. is supported by the General Wang Yaowu Stanford graduate fellowship; P.E.W. is supported by the US National Institutes of Health (GM75995); J.S.F. is supported by the US National Institutes of Health Early Independence Award (DP5OD009180). We acknowledge T. Alber, T. Kortemme, D. Keedy, D. Kern, D. Tawfik and R. Woldeyes for helpful discussions; N. Echols for advice on different treatments of hydrogen atoms in Phenix; J. Holton, J. Tanamachi and G. Meigs at Advanced Light Source Beamline 8.3.1 for support with X-ray data collection; B. Duggan and D. Boehr for chemical shift data on G121V ecDHFR complexes; and H. Axelrod and C. Trame for data collection and refinement of RT RBM39.

Author information

Authors and Affiliations

Authors

Contributions

H.v.d.B., G.B., P.E.W. and J.S.F. designed and performed experiments, analyzed data and prepared the manuscript; G.B. and J.S.F. collected data; and H.v.d.B., K.Y. and J.S.F. developed analytical tools.

Corresponding authors

Correspondence to Henry van den Bedem or James S Fraser.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Text and Figures

Supplementary Figures 1–7, Supplementary Tables 1–4 and Supplementary Note (PDF 6570 kb)

Supplementary Software

CONTACT (ZIP 481 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

van den Bedem, H., Bhabha, G., Yang, K. et al. Automated identification of functional dynamic contact networks from X-ray crystallography. Nat Methods 10, 896–902 (2013). https://doi.org/10.1038/nmeth.2592

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nmeth.2592

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