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:

Mechanism of O2 diffusion and reduction in FeFe hydrogenases

Abstract

FeFe hydrogenases are the most efficient H2-producing enzymes. However, inactivation by O2 remains an obstacle that prevents them being used in many biotechnological devices. Here, we combine electrochemistry, site-directed mutagenesis, molecular dynamics and quantum chemical calculations to uncover the molecular mechanism of O2 diffusion within the enzyme and its reactions at the active site. We propose that the partial reversibility of the reaction with O2 results from the four-electron reduction of O2 to water. The third electron/proton transfer step is the bottleneck for water production, competing with formation of a highly reactive OH radical and hydroxylated cysteine. The rapid delivery of electrons and protons to the active site is therefore crucial to prevent the accumulation of these aggressive species during prolonged O2 exposure. These findings should provide important clues for the design of hydrogenase mutants with increased resistance to oxidative damage.

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: FeFe hydrogenase and its inhibition by O2.
Figure 2: Change in catalytic H2-oxidation current versus time.
Figure 3: Potential dependence of the three rate constants defined in equation (1).
Figure 4: Markov state model for O2 diffusion into Cp hydrogenase.
Figure 5: Graphical representation of the relative free energies of the most important states (1–9) involved in oxygen reduction to water at the active site of the FeFe hydrogenase.
Figure 6: Proposed mechanism for aerobic inhibition of FeFe hydrogenase.

Similar content being viewed by others

References

  1. Lubitz, W., Ogata, H., Rüdiger, O. & Reijerse, E. Hydrogenases. Chem. Rev. 114, 4081–4148 (2014).

    Article  CAS  PubMed  Google Scholar 

  2. Flanagan, L. A. & Parkin, A. Electrochemical insights into the mechanism of NiFe membrane-bound hydrogenases. Biochem. Soc. Trans. 44, 315–328 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  3. Fritsch, J. et al. The crystal structure of an oxygen-tolerant hydrogenase uncovers a novel iron-sulphur centre. Nature 479, 249–252 (2011).

    CAS  PubMed  Google Scholar 

  4. Volbeda, A. et al. Crystal structure of the O2-tolerant membrane-bound hydrogenase 1 from Escherichia coli in complex with its cognate cytochrome b. Structure 21, 184–190 (2013).

    CAS  PubMed  Google Scholar 

  5. Hamdan, A. A. et al. Relation between anaerobic inactivation and oxygen tolerance in a large series of NiFe hydrogenase mutants. Proc. Natl Acad. Sci. USA 109, 19916–19921 (2012).

    PubMed  PubMed Central  Google Scholar 

  6. Plumeré, N. et al. A redox hydrogel protects hydrogenase from high-potential deactivation and oxygen damage. Nature Chem. 6, 822–827 (2014).

    Google Scholar 

  7. Fourmond, V. et al. Mechanism of protection of catalysts supported in redox hydrogel films. J. Am. Chem. Soc. 137, 5494–5505 (2015).

    CAS  PubMed  Google Scholar 

  8. Fourmond, V. et al. The mechanism of inhibition by H2 of H2-evolution by hydrogenases. Chem. Commun. 49, 6840–6842 (2013).

    CAS  Google Scholar 

  9. Pandey, A. S., Harris, T. V., Giles, L. J., Peters, J. W. & Szilagyi, R. K. Dithiomethylether as a ligand in the hydrogenase H-cluster. J. Am. Chem. Soc. 130, 4533–4540 (2008).

    CAS  PubMed  Google Scholar 

  10. Berggren, G. et al. Biomimetic assembly and activation of [FeFe]-hydrogenases. Nature 499, 66–69 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  11. Silakov, A. Wenk, B. Reijerse, E. & Lubitz, W. 14N HYSCORE investigation of the H-cluster of [FeFe] hydrogenase: evidence for a nitrogen in the dithiol bridge. Phys. Chem. Chem. Phys. 11, 6592–6599 (2009).

    CAS  PubMed  Google Scholar 

  12. Esselborn, J. et al. A structural view of synthetic cofactor integration into [FeFe]-hydrogenases. Chem. Sci. 7, 959–968 (2016).

    CAS  PubMed  Google Scholar 

  13. Mulder, D. W. et al. Stepwise [FeFe]-hydrogenase H-cluster assembly revealed in the structure of HydAΔEFG. Nature 465, 248–251 (2010).

    CAS  PubMed  Google Scholar 

  14. Ghirardi, M. L. Implementation of photobiological H2 production: the O2 sensitivity of hydrogenases. Photosynth. Res. 125, 383–393 (2015).

    CAS  PubMed  Google Scholar 

  15. Cohen, J., Kim, K., King, P., Seibert, M. & Schulten, K. Finding gas diffusion pathways in proteins: application to O2 and H2 transport in CpI [FeFe]-hydrogenase and the role of packing defects. Structure 13, 1321–1329 (2015).

    Google Scholar 

  16. Orain, C. et al. Electrochemical measurements of the kinetics of inhibition of two FeFe hydrogenases by O2 demonstrate that the reaction is partly reversible. J. Am. Chem. Soc. 137, 12580–12587 (2015).

    CAS  PubMed  Google Scholar 

  17. Baffert, C. et al. Hydrogen-activating enzymes: activity does not correlate with oxygen sensitivity. Angew. Chem. Int. Ed. 47, 2052–2055 (2008).

    CAS  Google Scholar 

  18. Stripp, S. T. et al. How oxygen attacks [FeFe] hydrogenases from photosynthetic organisms. Proc. Natl Acad. Sci. USA 106, 17331–17336 (2009).

    CAS  PubMed  PubMed Central  Google Scholar 

  19. Stiebritz, M. T. & Reiher, M. Theoretical study of dioxygen induced inhibition of [FeFe]-hydrogenase. Inorg. Chem. 48, 7127–7140 (2009).

    CAS  PubMed  Google Scholar 

  20. Kubas, A., Sancho, D. D., Best, R. B. & Blumberger, J. Aerobic damage of [FeFe] hydrogenases activation barriers for O2 chemical attachment. Angew. Chem. Int. Ed. 53, 4081–4084 (2014).

    CAS  Google Scholar 

  21. Lambertz, C. et al. O2 reactions at the six-iron active site (H-cluster) in [FeFe]-hydrogenase. J. Biol. Chem. 286, 40614–40623 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  22. Bruska, M. K., Stiebritz, M. T. & Reiher, M. Regioselectivity of H cluster oxidation. J. Am. Chem. Soc. 133, 20588–20603 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  23. Finkelmann, A. R., Stiebritz, M. T. & Reiher, M. Activation barriers of oxygen transformation at the active site of [FeFe] hydrogenases. Inorg. Chem. 53, 11890–11902 (2014).

    CAS  PubMed  Google Scholar 

  24. Hong, G. & Pachter, R. Inhibition of biocatalysis in [Fe–Fe] hydrogenase by oxygen: molecular dynamics and density functional theory calculations. ACS Chem. Biol. 7, 1268–1275 (2012).

    CAS  PubMed  Google Scholar 

  25. Swanson, K. D. et al. [FeFe]-hydrogenase oxygen inactivation is initiated at the H cluster 2Fe subcluster. J. Am. Chem. Soc. 137, 1809–1816 (2015).

    CAS  PubMed  Google Scholar 

  26. Greco, C. et al. Combining experimental and theoretical methods to learn about the reactivity of gas-processing metalloenzymes. Energy Environ. Sci. 7, 3543–3573 (2014).

    CAS  Google Scholar 

  27. Liebgott, P.-P. et al. Relating diffusion along the substrate tunnel and oxygen sensitivity in hydrogenase. Nature Chem. Biol. 6, 63–70 (2010).

    CAS  Google Scholar 

  28. Wang, P.-H. & Blumberger, J. Mechanistic insight into the blocking of CO diffusion in [NiFe]-hydrogenase mutants through multiscale simulation. Proc. Natl Acad. Sci. USA 109, 6399–6404 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  29. Wang, P.-h., Best, R. B. & Blumberger, J. Multiscale simulation reveals multiple pathways for H2 and O2 transport in a [NiFe]-hydrogenase. J. Am. Chem. Soc. 133, 3548–3556 (2011).

    CAS  PubMed  Google Scholar 

  30. De Sancho, D., Kubas, A., Wang, P.-h., Blumberger, J. & Best, R. B. Identification of mutational hot spots for substrate diffusion: application to myoglobin. J. Chem. Theory Comput. 11, 1919–1927 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  31. Baffert, C. et al. CO disrupts the reduced H-cluster of FeFe hydrogenase. A combined DFT and protein film voltammetry study. J. Am. Chem. Soc. 133, 2096–2099 (2011).

    CAS  PubMed  Google Scholar 

  32. Fourmond, V. et al. The oxidative inactivation of FeFe hydrogenase reveals the flexibility of the H-cluster. Nature Chem. 6, 336–342 (2014).

    CAS  Google Scholar 

  33. Léger, C., Dementin, S., Bertrand, P., Rousset, M. & Guigliarelli, B. Inhibition and aerobic inactivation kinetics of Desulfovibrio fructosovorans NiFe hydrogenase studied by protein film voltammetry. J. Am. Chem. Soc. 126, 12162–12172 (2004).

    PubMed  Google Scholar 

  34. Cornish, A. J., Gärtner, K., Yang, H., Peters, J. W. & Hegg, E. L. Mechanism of proton transfer in [FeFe]-hydrogenase from Clostridium pasteurianum. J. Biol. Chem. 286, 38341–38347 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  35. Knörzer, P. et al. Importance of the protein framework for catalytic activity of [FeFe]-hydrogenases. J. Biol. Chem. 287, 1489–1499 (2012).

    PubMed  Google Scholar 

  36. Hong, G., Cornish, A. J., Hegg, E. L. & Pachter, R. On understanding proton transfer to the biocatalytic [Fe–Fe] H sub-cluster in [Fe–Fe] H2ases: QM/MM MD simulations. Biochim. Biophys. Acta 1807, 510–517 (2011).

    CAS  PubMed  Google Scholar 

  37. Long, H., King, P. W. & Chang, C. H. Proton transport in Clostridium pasteurianum [FeFe] hydrogenase I: a computational study. J. Phys. Chem. B 118, 890–900 (2014).

    CAS  PubMed  Google Scholar 

  38. Morra, S. et al. Site saturation mutagenesis demonstrates a central role for cysteine 298 as proton donor to the catalytic site in CaHydA [FeFe]-hydrogenase. PLoS ONE 7, e48400 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  39. Morra, S. et al. The effect of a C298D mutation in CaHydA [FeFe]-hydrogenase: insights into the protein–metal cluster interaction by EPR and FTIR spectroscopic investigation. Biochim. Biophys. Acta 1857, 98–106 (2016).

    CAS  PubMed  Google Scholar 

  40. Goldet, G. et al. Electrochemical kinetic investigations of the reactions of [FeFe]-hydrogenases with carbon monoxide and oxygen: comparing the importance of gas tunnels and active-site electronic/redox effects. J. Am. Chem. Soc. 131, 14979–14989 (2009).

    CAS  PubMed  Google Scholar 

  41. Dey, S. et al. Electrocatalytic O2 reduction by [Fe–Fe]-hydrogenase active site models. J. Am. Chem. Soc. 136, 8847–8850 (2014).

    CAS  PubMed  Google Scholar 

  42. Wulff, P., Day, C., Sargent, F. & Armstrong, F. A. How oxygen reacts with oxygen-tolerant respiratory [NiFe]-hydrogenases. Proc. Natl Acad. Sci. USA 111, 6606–6611 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  43. Mulder, D. W. et al. Investigations on the role of proton-coupled electron transfer in hydrogen activation by [FeFe]-hydrogenase. J. Am. Chem. Soc. 136, 15394–15402 (2014).

    CAS  PubMed  Google Scholar 

  44. Ginovska-Pangovska, B. et al. Molecular dynamics study of the proposed proton transport pathways in [FeFe]-hydrogenase. Biochim. Biophys. Acta 1837, 131–138 (2014).

    CAS  PubMed  Google Scholar 

  45. Noth, J. et al. Lyophilization protects [FeFe]-hydrogenases against O2-induced H-cluster degradation. Sci. Rep. 5, 1–10 (2015).

    Google Scholar 

  46. Fournier, M., Dermoun, Z., Durand, M.-C. & Dolla, A. A new function of the Desulfovibrio vulgaris Hildenborough [Fe] hydrogenase in the protection against oxidative stress. J. Biol. Chem. 279, 1787–1793 (2004).

    CAS  PubMed  Google Scholar 

  47. Pandelia, M.-E. E. et al. Electronic structure of the unique [4Fe–3S] cluster in O2-tolerant hydrogenases characterized by 57Fe Mössbauer and EPR spectroscopy. Proc. Natl Acad. Sci. USA 110, 483–488 (2013).

    CAS  PubMed  Google Scholar 

  48. Stiebritz, M. T. & Reiher, M. Hydrogenases and oxygen. Chem. Sci. 3, 1739–1751 (2012).

    CAS  Google Scholar 

  49. Yano, J. et al. X-ray damage to the Mn4Ca complex in single crystals of photosystem II: a case study for metalloprotein crystallography. Proc. Natl Acad. Sci. USA 102, 12047–12052 (2005).

    CAS  PubMed  PubMed Central  Google Scholar 

  50. Glasoe, P. K. & Long, F. A. Use of glass electrodes to measure acidities in deuterium oxide. J. Phys. Chem. 64, 188–190 (1960).

    CAS  Google Scholar 

  51. Fourmond, V. QSoas: a versatile software for data analysis. Anal. Chem. 88, 5050–5052 (2016).

    CAS  PubMed  Google Scholar 

  52. Pronk, S. et al. GROMACS 4.5: a high-throughput and highly parallel open source molecular simulation toolkit. Bioinformatics 29, 845–854 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  53. Best, R. B. & Mittal, J. Protein simulations with an optimized water model: cooperative helix formation and temperature-induced unfolded state collapse. J. Phys. Chem. B. 114, 14916–14923 (2010).

    CAS  PubMed  Google Scholar 

  54. Abascal, J. L. F. & Vega, C. A general purpose model for the condensed phases of water: TIP4P/2005. J. Chem. Phys. 123, 234505–234512 (2005).

    CAS  PubMed  Google Scholar 

  55. Chang, C. H. & Kim, K. Density functional theory calculation of bonding and charge parameters for molecular dynamics studies on [FeFe] hydrogenases. J. Chem. Theory Comput. 5, 1137–1145 (2009).

    CAS  PubMed  Google Scholar 

  56. Dudko, O. K., Hummer, G. & Szabo, A. Intrinsic rates and activation free energies from single-molecule pulling experiments. Phys. Rev. Lett. 96, 108101–108104 (2006).

    PubMed  Google Scholar 

  57. Berezhkovskii, A., Hummer, G. & Szabo, A. Reactive flux and folding pathways in network models of coarse-grained protein dynamics. J. Chem. Phys. 130, 205102–205105 (2009).

    PubMed  PubMed Central  Google Scholar 

  58. Liu, C., Liu, T. & Hall, M. B. Influence of the density functional and basis set on the relative stabilities of oxygenated isomers of diiron models for the active site of [FeFe]-hydrogenase. J. Chem. Theory Comput. 11, 205–214 (2015).

    CAS  PubMed  Google Scholar 

Download references

Acknowledgements

The French teams were supported by CNRS, INSA, CEA, Agence Nationale de la Recherche (ANR-12-BS08-0014, ANR-14-CE05-0010) and the A*MIDEX project (n° ANR-11- IDEX-0001-02) funded by the «Investissements d’Avenir» French Government program, managed by the French National Research Agency (ANR). The authors thank R. van Lis for constructing the V296F and F290W mutants. D.D.S. acknowledges support from EPSRC grant no. EP/J016764/1 and an Ikerbasque Research Fellowship. A.K. was supported by EPSRC grant no. EP/J015571/1. R.B.B. was supported by the Intramural Research Program of the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health. J.B. thanks the Royal Society for a University Research Fellowship. This work was carried out on the HECToR and Archer computing facilities (Edinburgh), access to which was granted through the Materials Chemistry Consortium (EPSRC grants nos EP/F067496 and EP/L000202). The authors acknowledge the use of the UCL Legion High Performance Computing Facility (Legion@UCL) and associated support services in the completion of this work as well as the computational resources of the NIH HPC Biowulf cluster (http://hpc.nih.gov). D.D.S. acknowledges PRACE for awarding access to the FERMI resource based in Italy at CINECA. D.D.S. thanks A. Szabo and E. Rosta for discussions.

Author information

Authors and Affiliations

Authors

Contributions

A.K., C.O. and D.D.S. contributed equally to this work. All authors discussed the results and commented on the manuscript. A.K., D.D.S., R.B.B. and J.B. performed the calculations and analysed the data. C.O., M.S., C.B., V.F. and C.L. performed the electrochemical measurements and analysed the data. L.S., C.G., I.M.-S., P.S. and H.B. prepared the enzyme samples. A.K., D.D.S., R.B.B., C.B., V.F., J.B. and C.L. co-wrote the manuscript.

Corresponding authors

Correspondence to Jochen Blumberger or Christophe Léger.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary information

Supplementary information (PDF 7468 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kubas, A., Orain, C., De Sancho, D. et al. Mechanism of O2 diffusion and reduction in FeFe hydrogenases. Nature Chem 9, 88–95 (2017). https://doi.org/10.1038/nchem.2592

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

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