... equilibrium between myoglobin and a ligand can be represented by Mb + X G, k’ k MbX K = k’/k (3) where X is the ligand; Mb and MbX the unliganded and liganded forms of myoglobin; k’ and k, respectively,... and kinetics of the reactions of myoglobin and hemoglobin with the physiological ligand, oxygen, and with other substances and their relation to the structure of the proteins l Structure of Myoglobin. .. Functional Propertiesof Myoglobin The ferrous iron in myoglobin and hemoglobin reversibly binds a number of gaseousand nongaseousligands: 02, CO, NO, cyanide, alkalisocyanides, and aromatic nitroso