Article

Crystal structure of a truncated urease accessory protein UreF from Helicobacter pylori.

Division of Cancer Genomics and Proteomics, Ontario Cancer Institute, University Health Network, Toronto, Ontario M5G 2C4, Canada.
Proteins Structure Function and Bioinformatics (Impact Factor: 3.34). 10/2010; 78(13):2839-48. DOI: 10.1002/prot.22802
Source: PubMed

ABSTRACT Urease plays a central role in the pathogenesis of Helicobacter pylori in humans. Maturation of this nickel metalloenzyme in bacteria requires the participation of the accessory proteins UreD (termed UreH in H. pylori), UreF, and UreG, which form sequential complexes with the urease apoprotein as well as UreE, a metallochaperone. Here, we describe the crystal structure of C-terminal truncated UreF from H. pylori (residues 1-233), the first UreF structure to be determined, at 1.55 A resolution using SAD methods. UreF forms a dimer in vitro and adopts an all-helical fold congruent with secondary structure prediction. On the basis of evolutionary conservation analysis, the structure reveals a probable binding surface for interaction with other urease components as well as key conserved residues of potential functional relevance.

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