Premium
In diatoms, a transthylakoid proton gradient alone is not sufficient to induce a non‐photochemical fluorescence quenching
Author(s) -
Lavaud J,
Rousseau B,
Etienne A.-L
Publication year - 2002
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(02)02979-4
Subject(s) - xanthophyll , quenching (fluorescence) , electrochemical gradient , chemistry , non photochemical quenching , photochemistry , protonation , biophysics , violaxanthin , fluorescence , photoprotection , photosynthesis , biochemistry , lutein , zeaxanthin , carotenoid , biology , organic chemistry , ion , physics , quantum mechanics , membrane
Non‐photochemical fluorescence quenching (NPQ) in diatoms is associated with a xanthophyll cycle involving diadinoxanthin (DD) and its de‐epoxidized form, diatoxanthin (DT). In higher plants, an obligatory role of de‐epoxidized xanthophylls in NPQ remains controversial and the presence of a transthylakoid proton gradient (ΔpH) alone may induce NPQ. We used inhibitors to alter the amplitude of ΔpH and/or DD de‐epoxidation, and coupled NPQ. No ΔpH‐dependent quenching was detected in the absence of DT. In diatoms, both ΔpH and DT are required for NPQ. The binding of DT to protonated antenna sites could be obligatory for energy dissipation.