Crystallographic Analysis of the Pseudomonas aeruginosa Strain K122-4 Monomeric Pilin Reveals a Conserved Receptor-Binding ArchitectureAudette, G.F., Irvin, R.T., Hazes, B.
(2004) Biochemistry 43: 11427-11435
- PubMed: 15350129
- DOI: 10.1021/bi048957s
- Primary Citation of Related Structures:
- PubMed Abstract:
- Purification, crystallization and preliminary diffraction studies of the Pseudomonas aeruginosa strain K122-4 monomeric pilin
Audette, G.F.,Irvin, R.T.,Hazes, B.
(2003) Acta Crystallogr.,Sect.D 59: 1665
Adherence of pathogens to host cells is critical for the initiation of infection and is thus an attractive target for anti-infective therapeutics and vaccines. In the opportunistic human pathogen Pseudomonas aeruginosa, host-cell adherence is achieve ...
Adherence of pathogens to host cells is critical for the initiation of infection and is thus an attractive target for anti-infective therapeutics and vaccines. In the opportunistic human pathogen Pseudomonas aeruginosa, host-cell adherence is achieved predominantly by type IV pili. Analysis of several clinical strains of P. aeruginosa reveals poor sequence conservation between pilin genes, including the residues in the receptor-binding site. Interestingly, the receptor-binding sites appear to retain a conserved surface epitope because all Pseudomonas type IV pili recognize the same receptor on the host cell and cross-reactive antibodies specific for the receptor-binding site exist. Here, we present the crystallographic analysis of two crystal forms of truncated pilin from P. aeruginosa strain K122-4 (DeltaK122-4) at 1.54 and 1.8 A resolution, respectively. The DeltaK122-4 structure is compared to other crystallographically determined type IV pilin structures and an NMR structure of DeltaK122-4 pilin. A comparison with the structure of the highly divergent P. aeruginosa strain K (DeltaPAK) pilin indicates that the receptor-binding loop in both pilins forms a shallow depression with a surface that is formed by main-chain atoms. Conservation of this putative binding site is independent of the sequence as long as the main-chain conformation is conserved and could therefore explain the shared receptor specificity and antibody cross reactivity of highly divergent Pseudomonas type IV pilins.
Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada, T6G 2H7.