Jump to main content
Jump to site search

Volume 148, 2011
Previous Article Next Article

The quest for a functional substrate access tunnel in FeFe hydrogenase

Author affiliations

Abstract

We investigated di-hydrogen transport between the solvent and the active site of FeFe hydrogenases. Substrate channels supposedly exist and serve various functions in certain redox enzymes which use or produce O2, H2, NO, CO, or N2, but the preferred paths have not always been unambiguously identified, and whether a continuous, permanent channel is an absolute requirement for transporting diatomic molecules is unknown. Here, we review the literature on gas channels in proteins and enzymes and we report on the use of site-directed mutagenesis and various kinetic methods, which proved useful for characterizing substrate access to the active site of NiFe hydrogenase to test the putative “static” H2channel of FeFe hydrogenases. We designed 8 mutations in attempts to interfere with intramolecular diffusion by remodeling this putative route in Clostridium acetobutylicum FeFe hydrogenase, and we observed that none of them has a strong effect on any of the enzyme's kinetic properties. We suggest that H2 may diffuse either via transient cavities, or along a conserved water-filled channel. Nitrogenase sets a precedent for the involvement of a hydrophilic channel to conduct hydrophobic molecules.

Back to tab navigation

Supplementary files

Publication details

The article was received on 09 Mar 2010, accepted on 06 Apr 2010 and first published on 26 Aug 2010


Article type: Paper
DOI: 10.1039/C004099C
Citation: Faraday Discuss., 2011,148, 385-407
  •   Request permissions

    The quest for a functional substrate access tunnel in FeFe hydrogenase

    T. Lautier, P. Ezanno, C. Baffert, V. Fourmond, L. Cournac, J. C. Fontecilla-Camps, P. Soucaille, P. Bertrand, I. Meynial-Salles and C. Léger, Faraday Discuss., 2011, 148, 385
    DOI: 10.1039/C004099C

Search articles by author

Spotlight

Advertisements