1puo
Crystal structure of Fel d 1- the major cat allergen
OverviewOverview
The domestic cat (Felis domesticus) is one of the most important causes of allergic asthma worldwide. The dominating cat allergen, Fel d 1, is composed of two heterodimers. Recently, it has been shown that recombinant Fel d 1, consisting of chain 2 and chain 1 fused together without additional linker, has immunological properties indistinguishable from the natural heterodimeric protein. Herein, we report the crystal structure of recombinant monomeric Fel d 1 at 1.85-A resolution, determined by multi-wavelength anomalous diffraction using selenomethionine substituted protein. Fel d 1 is an all-helical protein and consists of eight helices. The two halves of the recombinant Fel d 1 molecule, corresponding to the wild-type Fel d 1 chains, are very similar in three-dimensional structure, despite the lack of significant sequence identity. The structure of the Fel d 1 presents a striking similarity to that of uteroglobin, a steroid-inducible cytokine-like molecule with anti-inflammatory and immunomodulatory properties. An internal, asymmetric cavity is formed in the Fel d 1 that could bind an endogenous ligand. The distribution of residues lining this cavity suggests that such a ligand must be amphipathic. The structure of Fel d 1 displays the localization of three previously defined Fel d 1 IgE epitopes on the surface of the protein. The three-dimensional structure provides a framework for rational design of hypoallergenic mutants aimed for treatment of cat allergy.
About this StructureAbout this Structure
1PUO is a Single protein structure of sequence from Felis catus. Full crystallographic information is available from OCA.
ReferenceReference
The crystal structure of the major cat allergen Fel d 1, a member of the secretoglobin family., Kaiser L, Gronlund H, Sandalova T, Ljunggren HG, van Hage-Hamsten M, Achour A, Schneider G, J Biol Chem. 2003 Sep 26;278(39):37730-5. Epub 2003 Jul 8. PMID:12851385 Page seeded by OCA on Sat May 3 05:30:18 2008