[Reactivation of oxygen accumulation function after complete removal of manganese from the photosystem II particles].

Reactivation of 0² evolution function has been studied in PS-2 particles after complete removal of Mn and water soluble 10, 17, 24, 33 kDa proteins, It has been shown that 0² evolution function in such particles can be reactivated by adding 5 μM Mn² and 20 mM Ca²(+). Preliminary illumination of the sample is necessary to exhibit the reactivation effect of 0² evolution. The maximum value of the reactivation of 0² evolution rate is about 60% of the control. Upon illumination of the reactivated particles with flashes of 1s duration and at a frequency of 0,1 Hz, 0² evolution occurs according to the mechanism analogous to that in the initial parties of PS 2. Thus the reactivation of water oxidation and 0² evolution after complete removal of Mn and water soluble 10, 17, 24, 33 kDa proteins resulting in the suppression of 0² evolution function has been shown for the first time and it can serve as a basic approach for profound investigation of the mechanism of photosynthetic water oxidation.