Involvement of uncoupled antenna chlorophylls in photoinhibition in thylakoids

Evidence is presented, by means of both fluorescence and action spectroscop y, that a small, spectroscopically heterogeneous population of both Chl a a nd Chl b molecules is present in isolated spinach thylakoids and is active in photoinhibition, The broadness of the action spectrum suggests that degr aded or incomplete ly assembled pigment-protein complexes may be involved. (C) 2001 Federation of European Biochemical Societies. Published by Elsevie r Science B.V. All rights reserved.