AI Article Synopsis
- The study investigated the primary electron acceptor X 320 in Tris-washed chloroplasts using fast repetitive flash spectroscopy, achieving a time resolution of about 1 microsecond.
- X 320 is reduced rapidly (within 1 microsecond) after a flash, whereas its reoxidation in the dark takes place primarily with kinetics of 100-200 microseconds.
- The findings suggest that the reaction centers of System II in chloroplasts have a high photochemical turnover rate, facilitated by quick charge recombination or fast cyclic electron flow.
Article Abstract
In Tris-washed chloroplasts the kinetics of the primary electron acceptor X 320 of reaction center II has been investigated by fast repetitive flash spectroscopy with a time resolution of approximately 1 mus. It has been found that X 320 is reduced by a flash in less than or equal to 1 mus. The subsequent reoxidation in the dark occurs mainly by a reaction with a 100-200 mus kinetics. The light-induced difference spectrum confirms X 320 to be the reactive species. From these results it is concluded that in Tris-washed chloroplasts the reaction centers of System II are characterized by a high photochemical turnover rate mediated either via rapid direct charge recombination or via fast cyclic electron flow.
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| http://dx.doi.org/10.1016/0005-2728(76)90214-0 | DOI Listing |
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