title: Amide H/D exchange in the thermal transition of bovine pancreatic ribonuclease A.
abstract: The H/D exchange behavior of RNase A at pH 2.5 at a number of temperatures spanning the thermal transition region has been examined by NMR spectroscopy. The amide proton of V116 has a slow rate of H/D exchange even at temperatures above the midpoint of the thermal transition. The H/D exchange behavior of the peptide corresponding to residues 105-124 of RNase A and the peptide corresponding to residues 115-117 is compared with that of RNase A, showing that folding/unfolding cannot be described by a two-state model, and that both short- and long-range interactions are responsible for the slow rate of H/D exchange.
authors.affiliation: Baker Laboratory of Chemistry, Cornell University, Ithaca, NY 14853-1301.
authors.forename: S
authors.initials: S
authors.lastname: Talluri
authors.forename: H A
authors.initials: HA
authors.lastname: Scheraga
mesh_terms: D000577:Amides; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D003903:Deuterium; D006859:Hydrogen; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000138:chemical synthesis; D010179:Pancreas / Q000201:enzymology; D011522:Protons; D012259:Ribonuclease, Pancreatic / Q000378:metabolism*
chemical_list: D000577:Amides; D009842:Oligopeptides; D011522:Protons; D006859:Hydrogen; D003903:Deuterium; D012259:Ribonuclease, Pancreatic