Download MendeleyCrystal Structure of Guaiacol and Phenol Bound to a Heme Peroxidase.
Murphy, E.J., Metcalfe, C.L., Nnamchi, C., Moody, P.C.E., Raven, E.L.(2012) FEBS J 279: 1632
- PubMed: 22093282
- DOI: https://doi.org/10.1111/j.1742-4658.2011.08425.x
- Primary Citation of Related Structures:
4A6Z, 4A71, 4A78, 4A7M - PubMed Abstract:
Guaiacol is a universal substrate for all peroxidases, and its use in a simple colorimetric assay has wide applications. However, its exact binding location has never been defined. Here we report the crystal structures of guaiacol bound to cytochrome c peroxidase (CcP). A related structure with phenol bound is also presented. The CcP-guaiacol and CcP-phenol crystal structures show that both guaiacol and phenol bind at sites distinct from the cytochrome c binding site and from the δ-heme edge, which is known to be the binding site for other substrates. Although neither guaiacol nor phenol is seen bound at the δ-heme edge in the crystal structures, inhibition data and mutagenesis strongly suggest that the catalytic binding site for aromatic compounds is the δ-heme edge in CcP. The functional implications of these observations are discussed in terms of our existing understanding of substrate binding in peroxidases [Gumiero A et al. (2010) Arch Biochem Biophys 500, 13-20].
Organizational Affiliation:
Department of Chemistry, University of Leicester, Leicester, UK.
