A possible redistribution of excitation energy in spinach chloroplasts due to nitrite ions

Abstract

The distribution of excitation energy between the two photosystems in the thylakoids of higher plants can be altered either by changing the concentration or valency of cations in the bathing medium (1) or by changing the degree of phosphorylation of the light harvesting chlorophyll proteins (LHCP) (2). The first procedure is believed to alter the balance between attractive and repulsive fences operating between the proteins which bind pigments and so causes them to move within the thylakoid membranes and because more closely associated with PSI or PS2. The second mechanism is probably the physiological method and involves a balance between the activities of a light-activated kinase and a Phosphorylase. This mechanism has the unique attribute of being sensitive to the distribution of excitation energy between the photosystems.