scholarly journals Temperature and Light Modulate the trans-Δ3-Hexadecenoic Acid Content of Phosphatidylglycerol: Light-harvesting Complex II Organization and Non-photochemical Quenching

2005 ◽  
Vol 46 (8) ◽  
pp. 1272-1282 ◽  
Author(s):  
Gordon R. Gray ◽  
Alexander G. Ivanov ◽  
Marianna Król ◽  
John P. Williams ◽  
Mobashoher U. Kahn ◽  
...  
Keyword(s):  
Acid Content ◽  
Light Harvesting ◽  
Photochemical Quenching ◽  
Hexadecenoic Acid ◽  
Light Harvesting Complex ◽  
Complex Ii ◽  
Light Harvesting Complex Ii ◽  
Non Photochemical Quenching

Macroorganisation and flexibility of thylakoid membranes

2019 ◽  
Vol 476 (20) ◽  
pp. 2981-3018 ◽  
Author(s):  
Petar H. Lambrev ◽  
Parveen Akhtar
Keyword(s):  
Light Harvesting ◽  
Current Knowledge ◽  
Three Dimensional ◽  
Photosynthetic Apparatus ◽  
Dynamic Responses ◽  
State Transitions ◽  
Photochemical Quenching ◽  
Light Harvesting Complex ◽  
Complex Ii ◽  
Light Harvesting Complex Ii

Abstract The light reactions of photosynthesis are hosted and regulated by the chloroplast thylakoid membrane (TM) — the central structural component of the photosynthetic apparatus of plants and algae. The two-dimensional and three-dimensional arrangement of the lipid–protein assemblies, aka macroorganisation, and its dynamic responses to the fluctuating physiological environment, aka flexibility, are the subject of this review. An emphasis is given on the information obtainable by spectroscopic approaches, especially circular dichroism (CD). We briefly summarise the current knowledge of the composition and three-dimensional architecture of the granal TMs in plants and the supramolecular organisation of Photosystem II and light-harvesting complex II therein. We next acquaint the non-specialist reader with the fundamentals of CD spectroscopy, recent advances such as anisotropic CD, and applications for studying the structure and macroorganisation of photosynthetic complexes and membranes. Special attention is given to the structural and functional flexibility of light-harvesting complex II in vitro as revealed by CD and fluorescence spectroscopy. We give an account of the dynamic changes in membrane macroorganisation associated with the light-adaptation of the photosynthetic apparatus and the regulation of the excitation energy flow by state transitions and non-photochemical quenching.

scholarly journals Photoprotective qH in Arabidopsis occurs in the light-harvesting complex II trimer

2021 ◽  
Author(s):  
Pierrick Bru ◽  
Collin J. Steen ◽  
Soomin Park ◽  
Cynthia L. Amstutz ◽  
Emily J. Sylak-Glassman ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Light Harvesting ◽  
Single Photon ◽  
Photochemical Quenching ◽  
Average Lifetime ◽  
Wild Type ◽  
Photosynthetic Membrane ◽  
Light Harvesting Complex ◽  
Complex Ii ◽  
Light Harvesting Complex Ii

Excess light can induce photodamage to the photosynthetic machinery, therefore plants have evolved photoprotective mechanisms such as non-photochemical quenching (NPQ). Different NPQ components have been identified and classified based on their relaxation kinetics and molecular players. The NPQ component qE is induced and relaxed rapidly (seconds to minutes), whereas the NPQ component qH is induced and relaxed slowly (hours or longer). Molecular players regulating qH have recently been uncovered, but the photophysical mechanism of qH and its location in the photosynthetic membrane have not been determined. Using time-correlated single-photon counting analysis of the Arabidopsis thaliana suppressor of quenching 1 mutant (soq1), which displays higher qH than the wild type, we observed shorter average lifetime of chlorophyll fluorescence in leaves and thylakoids relative to wild type. Comparison of isolated photosynthetic complexes from plants in which qH was turned ON or OFF revealed a chlorophyll fluorescence decrease specifically in the trimeric light-harvesting complex II (LHCII) fraction when qH was ON. LHCII trimers are composed of Lhcb1, 2 and 3 proteins, so CRISPR-Cas9 edited and T-DNA insertion lhcb1, lhcb2 and lhcb3 mutants were crossed with soq1. In soq1 lhcb1, soq1 lhcb2, and soq1 lhcb3, qH was not abolished, indicating that no single major Lhcb isoform is necessary for qH. Using transient absorption spectroscopy of isolated thylakoids, no spectral signatures for chlorophyll-carotenoid excitation energy quenching or charge transfer quenching were observed, suggesting that qH may occur through chlorophyll-chlorophyll excitonic interaction.

scholarly journals The Three Isoforms of the Light-harvesting Complex II

2004 ◽  
Vol 279 (35) ◽  
pp. 36884-36891 ◽  
Author(s):  
Joerg Standfuss ◽  
Werner Kühlbrandt
Keyword(s):  
Light Harvesting ◽  
Light Harvesting Complex ◽  
Complex Ii ◽  
Light Harvesting Complex Ii

scholarly journals AtFtsH6 is involved in the degradation of the light-harvesting complex II during high-light acclimation and senescence

2005 ◽  
Vol 102 (38) ◽  
pp. 13699-13704 ◽  
Author(s):  
A. Zelisko ◽  
M. Garcia-Lorenzo ◽  
G. Jackowski ◽  
S. Jansson ◽  
C. Funk
Keyword(s):  
Light Harvesting ◽  
High Light ◽  
Light Acclimation ◽  
Light Harvesting Complex ◽  
Complex Ii ◽  
Light Harvesting Complex Ii
Sign in / Sign up

Export Citation Format

Share Document