Reference : The chlorophyll a fluorescence induction curve in the green microalga Haematococcus p...
Scientific journals : Article
Life sciences : Biochemistry, biophysics & molecular biology
Life sciences : Phytobiology (plant sciences, forestry, mycology...)
The chlorophyll a fluorescence induction curve in the green microalga Haematococcus pluvialis: Further insight into the nature of the P-S-M fluctuation and its relationship with the "low-wave" phenomenon at steady-state
Fratamico, Anthony mailto [Université de Liège > Département des sciences de la vie > Physiologie végétale >]
Tocquin, Pierre mailto [Université de Liège > Département des sciences de la vie > Physiologie végétale >]
Franck, Fabrice mailto [Université de Liège > > Labo de Bioénergétique >]
Photosynthesis Research
Yes (verified by ORBi)
The Netherlands
[en] photosynthetic induction ; low-wave ; non-photochemical quenching ; chlorophyll a fluorescence ; Haematococcus pluvialis ; alternative electron transport
[en] Chlorophyll fluorescence is an information-rich signal which provides an access to the management of light absorbed by PSII. A good example of this is the succession of fast fluorescence fluctuations during light-induced photosynthetic induction after dark-adaptation. During this period, the fluorescence trace exhibits several inflexion points: O-J-I-P-S-M-T. Thereas the OJIP part of this kinetics has been the subject of many studies, the processes that underly the PSMT transient are less understood. Here, we report an analysis of the PSMT phase in the green microalga Haematococcus pluvialis in terms of electron acceptors and light use by photochemistry, fluorescence and non-photochemical quenching (NPQ). We identify additional sub-phases between P and S delimited by an inflexion point, that we name Q, found in the second time-scale. The P-Q phase expresses a transient photochemical quenching specifically due to alternative electron transport to oxygen. During the transition from Q to S, the NPQ increases and then relaxes during the S-M phase in about 1 min. It is suggested that this transient NPQ observed during induction is a high energy state quenching (qE) dependent the alternative electron transport to molecular oxygen. We further show that this NPQ is of the same nature than the NPQ, known as the low-wave phenomenon, which is transiently observed after a saturating light pulse given at steady-state. In both cases, the NPQ is oxygen-dependent. This NPQ is observed at external pH 6.0, but not at pH 7.5, which seems correlated with faster saturation of the PQ pool at pH 6.0.
Fonds pour la formation à la Recherche dans l'Industrie et dans l'Agriculture (Communauté française de Belgique) - FRIA ; Fonds de la Recherche Scientifique (Communauté française de Belgique) - F.R.S.-FNRS
Researchers ; Professionals ; Students

File(s) associated to this reference

Fulltext file(s):

Restricted access
Fratamico_tmp.pdfAuthor preprint220.34 kBRequest copy

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.