NMR studies of the quaternary structure and heterogeneity of nitrosyl- and methemoglobin.

摘要: NMR was used to study the quaternary structure of nitrosyl- and methemoglobin, kinetics equilibrium behavior nitric oxide binding, oxidation hemoglobin. The -9.6 ppm (from H2O) resonance as a measure nitrosylhemoglobin molecules in T structure. We found that stripped is 70% state below pH 6.4, R above. Inositol hexaphosphate (IHP) raises this transition point 7.5. For aquomethemoglobin, marker at -10 absent. In IHP, 6.5 all are state. At both higher lower they shift intensity decreases half its maximum 5.5 7.4. relative affinity binding alpha beta subunits inferred from intensities resonances -12 -18 ppm. Under conditions which exists state, NO binds subunit 10 times more strongly than it does subunit. kinetic experiments reveal two same rate dissociates 5 x 10(-3) s-1 10(-4) high pH, ligated rate. Potassium ferricyanide oxidation, 6.0 absence about 3 favorable for Addition IHP preferential slightly. 8.44, were oxidized