PHOTOCHEMISTRY OF THE REACTION CENTERS OF SYSTEM II UNDER REPETITIVE FLASH GROUP EXCITATION IN ISOLATED CHLOROPLASTS

作者：Hann-Jörg Eckert, Г. Ренгер · 发表于：Photochemistry and Photobiology · 年份：1980 · DOI：10.1111/j.1751-1097.1980.tb03736.x · 被引用次数：64 · 研究领域：Photosynthetic Processes and Mechanisms、Photoreceptor and optogenetics research、Light effects on plants

Abstract— Absorption changes induced in isolated chloroplasts by excitation with repetitive flash groups have been measured at 690 nm, indicating the photochemical turnover of chlorophyll‐aII (Chl‐αn), and at 480 nm and 513 nm respectively, reflecting via electrochromic effect the formation of a transmembrane electric field. The data are compared with measurements of oxygen evolution. In chloroplasts with practically fully intact oxygen evolving capacity it was found: 1. The initial amplitude of the 690 nm absorption change induced by the second flash as a function of the time tv between the first and second flash of a group increases with a half life of about 35 µs. On the other hand, the average oxygen yield due to the second flash as a function of the time tv rises with a half life of about 600 µs (and a kinetics in the ms‐range of minor extent), confirming the data of Vater et al. (1968). 2. Under far red background illumination, where contributions due to PS I in the µs‐range can be excluded, the difference spectrum in the red of the absorption changes induced by the first flash corresponds with that of the absorption changes induced by the second flash fired 200 µ after the first flash. 3. The pattern of the absorption changes at 690 nm induced by repetitive double flash groups at tv= 200 µs does not markedly change in normal chloroplasts by the presence of DBMIB†. Similar 690 nm absorption changes occur in trypsin treated chloroplasts, independent of the presence of DC...