Titration curves of interacting cytochrome b5 and hemoglobin by isoelectric focusing-electrophoresis

A strong interaction between cytochrome b5 and hemoglobin has been demonstrated by titration curves in isoelectric focusing - electrophoresis. The pH of maximum interaction is in the pH range 8.0-8.3, which suggests a predominant role of Lys of met hemoglobin in the binding to acidic amino acids of cytochrome b5. The stoichiometry of the complex appears to be 1:1 (cytochrome b5: hemoglobin subunit) with similar binding affinities for \u3b1 and \u3b2 chains