Peptide binding by chaperone SecB: implications for recognition of nonnative structure.

L L Randall

doi:10.1126/science.1631545

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PubMed · 1631545

Peptide binding by chaperone SecB: implications for recognition of nonnative structure.

L L Randall

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Abstract

The molecular basis for recognition of nonnative proteins by the molecular chaperone SecB was investigated with an in vitro assay based on the protection of SecB from proteolysis when a ligand is bound. The SecB tetramer has multiple binding sites for positively charged peptides. When the peptide binding sites are occupied, the complex undergoes a conformational change to expose hydrophobic sites that bind the fluorescent probe 1-anilinonaphthalene-8-sulfonate. A model is proposed for interaction of nonnative polypeptides with both hydrophilic and hydrophobic sites on SecB.

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Amino Acid Sequence Bacterial Proteins Binding Sites Electrophoresis, Polyacrylamide Gel In Vitro Techniques Models, Chemical Molecular Sequence Data Osmolar Concentration Peptides Protein Conformation Journal Article Research Support, U.S. Gov't, P.H.S.

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L L Randall. 1992-07-10. Peptide binding by chaperone SecB: implications for recognition of nonnative structure.. https://doi.org/10.1126/science.1631545

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