| Abstract: | Schenkman, Kenneth A., David R. Marble, David H. Burns, andEric O. Feigl. Myoglobin oxygen dissociation by multiwavelength spectroscopy. J. Appl. Physiol. 82(1):86-92, 1997. Multiwavelength optical spectroscopy was used todetermine the oxygen-binding characteristics for equine myoglobin.Oxygen-binding relationships as a function of oxygen tension weredetermined for temperatures of 10, 25, 35, 37, and 40°C, at pH 7.0. In addition, dissociation curves were determined at 37°C for pH6.5, 7.0, and 7.5. Equilibration was achieved with a myoglobinsolution, at the desired temperature and pH, and 16 oxygen-nitrogen gasmixtures of known oxygen fraction. Correction for the inevitablepresence of metmyoglobin was made by using a three-component leastsquares analysis and by correcting the end point oxymyoglobin spectrafor the presence of metmyoglobin. ThePO2 at which myoglobin ishalf-saturated with O2 (P50) was determined to be 2.39 Torr at pH 7.0 and 37°C. The myoglobin dissociationcurve was well fit by the Hill equation saturation = PO2/(PO2 + P50)]. |
