A, time course of rH-1 aggregation during Fe2+ oxidation. B, time course of rH-1 or EP-deleted rH-1 aggregation upon the addition of Fe2+ or Fe3+. The curve represents an average of six experimental measurements. C, relative scattered light intensity distribution curves for aporH-1 and aporH-1 plus Fe2+ ion. Conditions were as follows: [aporH-1] = 0.5 μm in 100 mm Mops (pH 7.0), 24–250 μm FeSO4, 25 °C.