(super 1)H NMR detection of immobilized water molecules within a strong distal hydrogen-bonding network of substrate-bound human heme oxygenase-1

The (super 1)H NMR identifies the water molecules localized within a protein through NOEs between the bulk water signal and individual protein resonances. Water molecules roles can range from simple impediments to rapid ligation, as in globins, to participation in important hydrogen-bonding networks in the catalytic cycles of enzymes such as the cytochromes P450.