Role of electron-transfer quenching of chlorophyll fluorescence by carotenoids in non-photochemical quenching of green plants.
NPQ (non-photochemical quenching) is a fundamental photosynthetic mechanism by which plants protect themselves against excess excitation energy and the resulting photodamage. A discussed molecular mechanism of the so-called feedback de-excitation component (qE) of NPQ involves the formation of a quenching complex. Recently, we have studied the influence of formation of a zeaxanthin-chlorophyll complex on the excited states of the pigments using high-level quantum chemical methodology. In the case of complex formation, electron-transfer quenching of chlorophyll-excited states by carotenoids is a relevant quenching mechanism. Furthermore, additionally occurring charge-transfer excited states can be exploited experimentally to prove the existence of the quenching complex during NPQ.
Dreuw
A
A
Institute for Physical and Theoretical Chemistry, Johann Wolfgang Goethe-University Frankfurt, Marie Curie-Str. 11, 60439 Frankfurt am Main, Germany. andreas.dreuw@theochem.uni-frankfurt.de
Fleming
G R
GR
Head-Gordon
M
M
D002338:Carotenoids / Q000494:pharmacology*; D002734:Chlorophyll / Q000378:metabolism*; D004579:Electron Transport; D010944:Plants / Q000187:drug effects / Q000378:metabolism*; D024341:Xanthophylls / Q000494:pharmacology; D065146:Zeaxanthins; D019207:beta Carotene / Q000031:analogs & derivatives / Q000378:metabolism
D024341:Xanthophylls; D065146:Zeaxanthins; D019207:beta Carotene; D002734:Chlorophyll; D002338:Carotenoids