title: Chaperoning Anfinsen: the steric foldases.
abstract: Some proteins are so much resistant to proteolysis and unfolding that they violate folding rules shared by the vast majority of proteins. These unusual proteins manage to fold into an active native conformation that is thermodynamically at best marginally, but often even less stable than the unfolded state. A huge energetic barrier traps these proteins kinetically in the folded state. The drawback of this situation is the need for a specialized chaperone that adds steric information to the proteins to cross this barrier on the folding pathway. Until now, our knowledge of these intriguing chaperones was restricted to the prodomains of secreted proteases, which function intramolecularly. Recent research has added more examples, which now include the membrane-anchored lipase-specific foldase and the pilus subunit specific chaperone, both acting intermolecularly. The case of the pilin chaperone is somewhat deviant in that steric information is definitely provided, but the pilus subunit adopts a thermodynamically favourable stable conformation.
authors.affiliation: Department of Molecular and Cellular Interactions, VIB and Department of Ultrastructure, Free University Brussels, Brussels, Belgium.
authors.forename: Kris
authors.initials: K
authors.lastname: Pauwels
authors.forename: Inge
authors.initials: I
authors.lastname: Van Molle
authors.forename: Jan
authors.initials: J
authors.lastname: Tommassen
authors.forename: Patrick
authors.initials: P
authors.lastname: Van Gelder
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry* / Q000378:metabolism*; D011487:Protein Conformation; D017510:Protein Folding; D013816:Thermodynamics
chemical_list: D001426:Bacterial Proteins; D018832:Molecular Chaperones