Necessity of the divalent cation in the reaction between EAC1-8hu and C9gp.
The reaction of EAC1-8hu and C9gp could not generate E* in 0.09 M EDTA solution. In 0.001 M EDTA solution, EAC1-8hu could not fix C9gp. But E* formation was observed in the buffer containing low concentration of divalent cations. Of the tested cations, Ca++ was most effective and its optimal concentration was 2 X 10(-7) M.