Hydrogen-exchange kinetics in the cold denatured state of ribonuclease A.
Ribonuclease A (RNase A) exhibits a well-defined cold denaturation transition when examined at high pressure (3 kbar) and low temperatures (below -10 degrees C). Our main interest in this study was to investigate the pressure-assisted cold denatured state of RNase A by hydrogen exchange techniques. The protection factors obtained from the kinetic data are similar to those obtained previously for RNase A denatured by exposure to high pressure near its temperature of maximum stability, but differ markedly from those in thermally denatured RNase A. A qualitative analysis of the hydrogen-exchange rates suggests that cold denatured RNase A behaves markedly differently from a random coil, probably due to patches of residual secondary structure.
Nash
D
D
Department of Chemistry, School of Chemical Sciences, University of Illinois at Urbana-Champaign 61801, USA.
Lee
B S
BS
Jonas
J
J
D000577:Amides / Q000737:chemistry; D003080:Cold Temperature; D006639:Histidine / Q000737:chemistry; D007700:Kinetics; D011312:Pressure; D011489:Protein Denaturation; D011522:Protons; D012259:Ribonuclease, Pancreatic / Q000737:chemistry*
D000577:Amides; D011522:Protons; D006639:Histidine; D012259:Ribonuclease, Pancreatic