Studies on the mechanisms of delayed and stimulated delayed fluorescence of chloroplasts

Dependence of Delayed Luminescence upon Adenosine Triphosphatase Activity in Chlorella

“…Miles and Jagendorf (31) first described a stimulation of delayed luminescence by a membrane potential induced by an ion gradient. This effect has been more quantitatively studied by Barber and Kraan (5), Kraan (26), and Kraan et al (27). As pointed out by Crofts et al (10), this effect can be interpreted if one assumes that a membrane potential, positive inside and negative outside the thylakoid, would facilitate the charge recombination by decreasing the activation energy of the reaction.…”

“…Miles and Jagendorf (31) first described a stimulation of delayed luminescence by a membrane potential induced by an ion gradient. This effect has been more quantitatively studied by Barber and Kraan (5), Kraan (26), and Kraan et al (27) detected by the 520 nm absorption change (23), when other parameters which control delayed luminescence are kept constant. Delayed luminescence can also be stimulated by acid-base transition (26,27,30) or by a light-induced proton gradient as shown by Wraight and Crofts (35).…”

“…This effect has been more quantitatively studied by Barber and Kraan (5), Kraan (26), and Kraan et al (27) detected by the 520 nm absorption change (23), when other parameters which control delayed luminescence are kept constant. Delayed luminescence can also be stimulated by acid-base transition (26,27,30) or by a light-induced proton gradient as shown by Wraight and Crofts (35).Living cells differ from chloroplasts isolated either from algae or from higher plants with respect to the rates of the back reaction and of the intensity of delayed luminescence. After a preillumination in the presence of DCMU, the reoxidation of reduced acceptor Q-can only occur by the back reaction, which is faster in living cells (ti/2 -0.75 s) than in isolated chloroplasts (t1/2 -2.5 s) (8).…”

“…We reported (20) that in Chlorella there is a strict correlation between the intensity of delayed luminescence and the membrane potential detected by the 520 nm absorption change (23), when other parameters which control delayed luminescence are kept constant. Delayed luminescence can also be stimulated by acid-base transition (26,27,30) or by a light-induced proton gradient as shown by Wraight and Crofts (35).…”

Requirement of an acidic proton in substances which act as accelerators of the deactivation reactions in the water‐splitting enzyme system of photosynthesis

“…[ADRYtot] = total amount of the ADRY-agent, Since the ADRY-agents act in the water-splitting enzyme system which is postulated to be localized near the inner phase of the thylakoid [8,9], it is assumed that the ADRY-agent concentration of the inner aqueous phase is relevant for the ADRY-effect. Therefore, only a two-phase system will be considered, with k = i or o (i = inner, o = outer aqueous phase of the thylakoid, respectively).…”