Backbone thioester exchange: a new approach to evaluating higher order structural stability in polypeptides.
An amide bond has been replaced by a thioester in bovine pancreatic polypeptide (bPP) to allow rapid and reversible (dynamic) exchange of the alpha-helical segment with other thiols in solution. We have begun to study the higher order structural stability of bPP by measuring the equilibrium constant of the "backbone thioester exchange" (BTE) reaction. The extent to which the equilibrium (KBTE) favors one set of peptides over the other, which can be easily measured, can be directly correlated to the energy gained from favorable noncovalent interactions that occur between peptide segments on either side of the thioester bond (Kfold).
Woll
Matthew G
MG
Department of Chemistry, University of Wisconsin--Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA.
Gellman
Samuel H
SH
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D010191:Pancreatic Polypeptide / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D013329:Structure-Activity Relationship; D013816:Thermodynamics; D014443:Tyrosine / Q000737:chemistry
D014443:Tyrosine; D010191:Pancreatic Polypeptide