Protein Structure Influences Redox Stability, Oxygen Affinity, and Heat-Induced Denaturation Properties of Bovine Myoglobin, Hemoglobin, and Cytochrome c

While past research has predominantly focused on the role of myoglobin in meat color, investigations into the contributions of hemoglobin and cytochrome c are limited. Cytochrome c has the highest redox stability (P < 0.05), followed by myoglobin and hemoglobin. Electrochemistry analysis revealed that cytochrome c has a greater capacity (P < 0.05) to reduce than myoglobin and hemoglobin. Differential scanning calorimetry indicates that cytochrome c was most stable to heat (P < 0.05), while no differences were noted between myoglobin and hemoglobin. Structural analysis noted that greater heat and redox stability of cytochrome c might be attributed to fewer histidine residues (3) and more covalent bonds (4) than myoglobin (13), hemoglobin α (10), and hemoglobin β (6). This study suggests that the amino acid sequence and number of covalent bonds can impact the redox stability and heat-induced denaturation properties of myoglobin, hemoglobin, and cytochrome c.