Interaction with GroEL destabilises non-amphiphilic secondary structure in a peptide.
The Escherichia coli molecular chaperone GroEL can functionally interact with non-native forms of many proteins. An inherent property of non-native proteins is the exposure of hydrophobic residues and the presence of secondary structure elements. Whether GroEL unfolds or stabilises these structural elements in protein substrates as a result of binding has been the subject of extended debate in the literature. Based on our studies of model peptides of pre-formed helical structure, we conclude that the final state of a GroEL-bound substrate is dependent on the conformational flexibility of the substrate protein and the distribution of hydrophobic residues, with optimal association when these are able to present a cluster of hydrophobic residues in the binding interface.
Preuss
M
M
Imperial College Genetics Therapies Centre, Department of Chemistry, Imperial College of Science, Technology and Medicine, South Kensington, London, UK.
Miller
A D
AD
D018834:Chaperonin 60 / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D006860:Hydrogen Bonding; D009842:Oligopeptides / Q000737:chemistry*; D017510:Protein Folding; D017433:Protein Structure, Secondary
D018834:Chaperonin 60; D009842:Oligopeptides