Hydration of methemoglobin studied by <i>in silico</i> modeling and dielectric spectroscopy

The hemoglobin concentration of 35 g/dl human red blood cells is close to the solubility threshold. Using microwave dielectric spectroscopy, we have assessed amount water associated with hydration shells methemoglobin as a function its in presence or absence ions. We estimated water–hemoglobin interactions interpret obtained data. Within range 5–10 methemoglobin, ions play an important role defining free-to-bound ratio competing recruit molecules for shell. At higher concentrations, major contributor recruitment Furthermore, bound does not change increased from 15 30 g/dl, remaining at level ∼20% total intracellular pool. theoretical evaluation free and corresponds experimental results shows that molecule binds about 1400 molecules. These observations suggest within physiological one, are so each other their interact. In this case, orientation most likely stochastic, but rather supports partial neutralization positive negative charges protein surface. deformation cell shape rearrangement these structures.