Recent Studies Have Shown That the H-Bond Between the Distal

Multiple Choice

Recent studies have shown that the H-bond between the distal histidine and oxygen molecule in myoglobin has a strength of ~ 15 kJ/mol, but in hemoglobin, the strength of the bond is only ~8 kJ/mol. What does this suggest about the differences between myoglobin and hemoglobin?

A) myoglobin binds oxygen more strongly than hemoglobin
B) hemoglobin binds oxygen more strongly than myoglobin
C) the iron in myoglobin is more easily oxidized than in hemoglobin
D) the iron in hemoglobin is more easily oxidized than in myoglobin
E) none of the above