Thermoluminescence and Delayed Luminescence Characterization of Photosystem IIa and Photosystem IIp Reaction Centers

Éva Hideg and Sándor Demeter Institute of Plant Physiology, Biological Research Center, Szeged, P.O. Box 521. Hungary, H-6701 Z. Naturforsch. 43c , 596-600 (1988); received May 2, 1988 Photosynthesis, Photosystem I I , Thermoluminescence, Delayed Luminescence The thermoluminescence and delayed luminescence characteristics of PS I I „ and PS I I p centers were investigated in B B Y particles and stroma thylakoids, respectively. The B B Y particles exhibited a thermoluminescence band at 25 °C (B band) which was associated wi th the charge recombination of the S 2 Q b " redox couple and underwent period-2 oscillation in a sequence of flashes. In the flash-induced decay of delayed luminescence of B B Y particles a component with a half-t ime of 34 s corresponded to the B thermoluminescence band and was also assigned to S2OB charge recombination. No corresponding thermoluminescence or delayed luminescence components associated with the secondary acceptor OB could be observed in the glow curve or delayed luminescence decay of stroma thylakoids. These observations indicate that unlike PS I I a the PS Hp centers are not associated with the two-electron gate, 0 B .