Characterization of the Fast and Slow Reversible Components of Non-Photochemical Quenching in Isolated Pea Thylakoids by Picosecond Time-Resolved Chlorophyll Fluorescence Analysis†

Biochemistry ◽  
1999 ◽  
Vol 38 (39) ◽  
pp. 12718-12726 ◽  
Author(s):  
Michael Richter ◽  
Reimund Goss ◽  
Birgit Wagner ◽  
Alfred R. Holzwarth
Keyword(s):  
Chlorophyll Fluorescence ◽  
Fluorescence Analysis ◽  
Photochemical Quenching ◽  
Time Resolved ◽  
Non Photochemical Quenching ◽  
Chlorophyll Fluorescence Analysis

Non-photochemical quenching of chlorophyll a fluorescence: early history and characterization of two xanthophyll-cycle mutants of Chlamydomonas reinhardtii

2002 ◽  
Vol 29 (10) ◽  
pp. 1141 ◽  
Author(s):  
Govindjee ◽  
Manfredo J. Seufferheld
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Oxygen Evolution ◽  
Xanthophyll Cycle ◽  
Photochemical Quenching ◽  
Chl A ◽  
Fluorescence Transient ◽  
Chl A Fluorescence ◽  
Non Photochemical Quenching

This paper deals first with the early, although incomplete, history of photoinhibition, of 'non-QA-related chlorophyll (Chl) a fluorescence changes', and the xanthophyll cycle that preceded the discovery of the correlation between non-photochemical quenching of Chl a fluorescence (NPQ) and conversion of violaxanthin to zeaxanthin. It includes the crucial observation that the fluorescence intensity quenching, when plants are exposed to excess light, is indeed due to a change in the quantum yield of fluorescence. The history ends with a novel turn in the direction of research — isolation and characterization of NPQ xanthophyll-cycle mutants of Chlamydomonas reinhardtii Dangeard and Arabidopsis thaliana (L.) Heynh., blocked in conversion of violaxanthin to zeaxanthin, and zeaxanthin to violaxanthin, respectively. In the second part of the paper, we extend the characterization of two of these mutants (npq1, which accumulates violaxanthin, and npq2, which accumulates zeaxanthin) through parallel measurements on growth, and several assays of PSII function: oxygen evolution, Chl a fluorescence transient (the Kautsky effect), the two-electron gate function of PSII, the back reactions around PSII, and measurements of NPQ by pulse-amplitude modulation (PAM 2000) fluorimeter. We show that, in the npq2 mutant, Chl a fluorescence is quenched both in the absence and presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). However, no differences are observed in functioning of the electron-acceptor side of PSII — both the two-electron gate and the back reactions are unchanged. In addition, the role of protons in fluorescence quenching during the 'P-to-S' fluorescence transient was confirmed by the effect of nigericin in decreasing this quenching effect. Also, the absence of zeaxanthin in the npq1 mutant leads to reduced oxygen evolution at high light intensity, suggesting another protective role of this carotenoid. The available data not only support the current model of NPQ that includes roles for both pH and the xanthophylls, but also are consistent with additional protective roles of zeaxanthin. However, this paper emphasizes that we still lack sufficient understanding of the different parts of NPQ, and that the precise mechanisms of photoprotection in the alga Chlamydomonas may not be the same as those in higher plants.

Chlorophyll fluorescence from spinach leaves: Resolution of non-photochemical quenching

1989 ◽  
Vol 974 (3) ◽  
pp. 289-293 ◽  
Author(s):  
M. Hodges ◽  
G. Comic ◽  
J.-M. Briantais
Keyword(s):  
Chlorophyll Fluorescence ◽  
Photochemical Quenching ◽  
Non Photochemical Quenching ◽  
Spinach Leaves

Methods of Selection for Chilling Tolerance in Nepalese Rice by Chlorophyll Fluorescence Analysis

Crop Science ◽  
1995 ◽  
Vol 35 (1) ◽  
pp. 90-94 ◽  
Author(s):  
B. R. Sthapit ◽  
J. R. Witcombe ◽  
J. M. Wilson
Keyword(s):  
Chlorophyll Fluorescence ◽  
Fluorescence Analysis ◽  
Chilling Tolerance ◽  
Selection For ◽  
Chlorophyll Fluorescence Analysis
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