Structural basis of chaperone function and pilus biogenesis.

F G Sauer; K Fütterer; J S Pinkner; K W Dodson; S J Hultgren; G Waksman

doi:10.1126/science.285.5430.1058

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PubMed · 10446050

Structural basis of chaperone function and pilus biogenesis.

F G Sauer·K Fütterer·J S Pinkner·K W Dodson·S J Hultgren·G Waksman

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Abstract

Many Gram-negative pathogens assemble architecturally and functionally diverse adhesive pili on their surfaces by the chaperone-usher pathway. Immunoglobulin-like periplasmic chaperones escort pilus subunits to the usher, a large protein complex that facilitates the translocation and assembly of subunits across the outer membrane. The crystal structure of the PapD-PapK chaperone-subunit complex, determined at 2.4 angstrom resolution, reveals that the chaperone functions by donating its G(1) beta strand to complete the immunoglobulin-like fold of the subunit via a mechanism termed donor strand complementation. The structure of the PapD-PapK complex also suggests that during pilus biogenesis, every subunit completes the immunoglobulin-like fold of its neighboring subunit via a mechanism termed donor strand exchange.

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Amino Acid Sequence Bacterial Proteins Crystallography, X-Ray Escherichia coli Escherichia coli Proteins Fimbriae Proteins Fimbriae, Bacterial Models, Molecular Molecular Chaperones Molecular Sequence Data Periplasmic Proteins Protein Conformation Protein Folding Protein Structure, Secondary Sequence Alignment Journal Article Research Support, U.S. Gov't, P.H.S.

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F G Sauer, K Fütterer, J S Pinkner, K W Dodson, S J Hultgren, G Waksman. 1999-08-13. Structural basis of chaperone function and pilus biogenesis.. https://doi.org/10.1126/science.285.5430.1058

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