title: The effect of temperature on the reaction of carbon monoxide with oxygenated haemoglobin.
abstract: 1. The rate at which carbon monoxide displaces oxygen from its combination with haemoglobin in solution, has been measured spectrophotometrically, using a rapid-mixing stopped-flow technique. 2. In the presence of carbon dioxide, the reaction proceeds by a unimolecular dissociation, with a rate constant r. 3. The relationship of the reciprocal of r to the ratio PO2/PCO is non-linear, and a different curve is obtained at each carbon monoxide concentration. 4. From measurements of the rate constant at temperatures between 5 and 35 degrees C, it is concluded that the non-linearity is due to the formation at a finite rate of an intermediate complex, CO2Hb4O6, by the reaction of carbon dioxide with Hb4O6.
mesh_terms: D002248:Carbon Monoxide / Q000097:blood*; D006454:Hemoglobins / Q000378:metabolism*; D007700:Kinetics; D010108:Oxyhemoglobins / Q000378:metabolism*; D013053:Spectrophotometry; D013696:Temperature
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; D002248:Carbon Monoxide