Treatment of photosystem Ⅱ particles with NaCl-washings,low-pH washings or detergent OG-solubilizings inhibited oxygen evolution and the inhibition was reversed by addition of exogenous Ca^(2+). Dynamic analysis with...Treatment of photosystem Ⅱ particles with NaCl-washings,low-pH washings or detergent OG-solubilizings inhibited oxygen evolution and the inhibition was reversed by addition of exogenous Ca^(2+). Dynamic analysis with Ca^(2+)reconstitution revealed two Ca^(2+)binding sites with different affinities in the NaCl-washed PS Ⅱ particles or in the low-pH-treated ones.Oxygen-evolving PS Ⅱ core complex also con- tained the high and low affinity Ca^(2+)binding sites.Ca^(2+)enhanced the intensity of fluorescence emission of PS Ⅱ core complex.These results suggest that calcium play two roles in PS Ⅱ,the low affinity Ca^(2+)is associ- ated with energy transfer while the high affinity Ca^(2+)is concerned with water splitting reaction.展开更多
基金the National Natural Science Foundation of China
文摘Treatment of photosystem Ⅱ particles with NaCl-washings,low-pH washings or detergent OG-solubilizings inhibited oxygen evolution and the inhibition was reversed by addition of exogenous Ca^(2+). Dynamic analysis with Ca^(2+)reconstitution revealed two Ca^(2+)binding sites with different affinities in the NaCl-washed PS Ⅱ particles or in the low-pH-treated ones.Oxygen-evolving PS Ⅱ core complex also con- tained the high and low affinity Ca^(2+)binding sites.Ca^(2+)enhanced the intensity of fluorescence emission of PS Ⅱ core complex.These results suggest that calcium play two roles in PS Ⅱ,the low affinity Ca^(2+)is associ- ated with energy transfer while the high affinity Ca^(2+)is concerned with water splitting reaction.
