Light dependent quenching, inhibition

Shown in Table II are I q values for inhibition of electron transport in spinach thylakoids (water to ferricyanide) and the associated phosphorylation reaction by the test compounds. Also included are I5Q values for inhibition of the light-dependent quenching of atebrin fluorescence and the ratio obtained by dividing the Icq for the atebrin response by the I q for inhibition of photophosphorylation. The relative order of inhibitory potency for some of the compounds for inhibition of ferricyanide reduction has been reported previously (12). For the herbicides,... 

Lipophilic tertiary amines (t-amines) are effective inhibitors of photophosphorylation (1-3) Bound up with the inhibition, light-induced uptake of (l C)-methylamine and quenching of 9 afflinoacridine (9 AA) fluorescence disappear. This indicates that inhibition of ATP synthesis may be related to a decline of the transthylakoid proton gradient, ApH (4). IntriguingTy, a strong pH-dependent control of electron flow was maintained in the presence of t-amines (3 5) despite of the low ApH Therefore, t-amines were termed selective uncouplers (1). 

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