Structural stability and solvent denaturation of myoglobin.

As judged from the midpoints of the denaturation transition of 31 water-miscible alcohols, ureas, and amides, the effectiveness of these denaturing agents on sperm-whale myoglobin increases with increasing chain length and hydrocarbon content, as expected in view of the disorganization of the hydrophobic interior of this protein. Increase in the hydroxyl content, blocking of the functional amino groups of the ureas and amides by alkyl substitution, and branching of the hydrocarbon portion of the denaturants are of less importance in determining the effectiveness of the denaturants.