Evidence for the delayed photoactivation of electrogenic electron transport in chloroplast membranesстатья
Информация о цитировании статьи получена из
Scopus,
Web of Science
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
Аннотация:Time-courses of the electric potential at chloroplast thylakoid membranes and of a chlorophyll fluorescence were measured simultaneously on individual chloroplasts of Anthoceros under the action of intensive 1.5 s light pulses. There were two distinct peaks of the electrical potential in the induction curve and a transient minimum that occurred at about 200 ms from the onset of illumination. The decay of the potential after an initial peak occurred concomitantly with an increase of the fluorescence up to a maximum P. The location of the transient minimum of the potential varied, depending on the preceding dark period, but it coincided with the location of the fluorescence maximum P. A delayed rise of the potential in dark-adapted chloroplasts was accompanied with a transient decline of the fluorescence. Both the secondary rise of the potential and the fluorescence decline from P to S1 were suppressed by preillumination and abolished completely by DBMIB or dithionite. It is concluded that the second peak of the potential and a concomitant decline of the fluorescence are different manifestations of a delayed acceleration of PS-I-associated electron transport, which is coupled with electrogenic proton displacements across the thylakoid membrane.