The Influence of Pressure on The Low-Temperature Kinetics of Myoglobin

• Main Author: Sorensen, Larry Brice
• Format: Text
• Language: unknown
• Published: 1980
• Subjects: Physics; Molecular; Sperm whale
• Online Access: http://hdl.handle.net/2142/77188

155 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1980. The recombination of carbon monoxide and dioxygen to horse and sperm whale myoglobin at low temperatures (60 - 160K) was studied using high pressure flash photolysis techniques. By comparing the pressure dependence when the system is first frozen and then pressurized with the pressure dependence when the system is first pressurized and then frozen, the total volume change for the reaction can be resolved into an activation volume component and a conformational volume component. Strong evidence requiring both conformational volume and activation volume components was found. Over the pressure range studied (0.1 - 200 MPa) the observed volume changes were independent of the applied pressure. At low temperatures, the recombination reaction must be described by a distribution of activation enthalpies. A simple configuration coordinate model was developed which predicts distributions in excellent agreement with the observed distributions.