Studies on animal hemoglobins II. The influence of inorganic phosphate on the physico-chemical and physiological properties of the hemoglobin of the adult chicken

The equilibrium of dilute and concentrated adult chicken red blood cell hemolysates with O₂ has been studied using potassium phosphate buffers and NaCl solutions of different molarities. The results indicate an increase in O₂ affinity with increase in ionic strength. The same phenomenon was observed for the isolated minor hemoglobin component; the isolated major hemoglobin component showed a rather high O₂ affinity at low ionic strength, which decreased with increase in molarity. The minor hemoglobin fraction exhibited an ability to form rather stable complexes with phosphate ions; such complexes possessed a high O₂ affinity at low ionic strength. The data also indicated that the two hemoglobin components in a hemolysate interacted with each other. This extra-molecular interaction interfered with the physiologic properties of the hemolysate. No physico-chemical interaction could be detected, as was demonstrated by the determination of the molecular weight and by viscosity measurements.