A kinetic model of rapidly reversible nonphotochemical quenching

Autor:	Krishna K. Niyogi, Julia Zaks, Kapil Amarnath, Graham R. Fleming, David Kramer
Rok vydání:	2012
Předmět:	Multidisciplinary Photosystem II Biology Photosynthesis Photochemistry Models Biological chemistry.chemical_compound Light intensity Models Chemical chemistry Commentaries Photoprotection Chlorophyll Thylakoid Chlorophyll fluorescence Violaxanthin
Zdroj:	Proceedings of the National Academy of Sciences. 109:15757-15762
ISSN:	1091-6490 0027-8424
Popis:	Oxygen-evolving photosynthetic organisms possess nonphotochemical quenching (NPQ) pathways that protect against photo-induced damage. The majority of NPQ in plants is regulated on a rapid timescale by changes in the pH of the thylakoid lumen. In order to quantify the rapidly reversible component of NPQ, called qE, we developed a mathematical model of pH-dependent quenching of chlorophyll excitations in Photosystem II. Our expression for qE depends on the protonation of PsbS and the deepoxidation of violaxanthin by violaxanthin deepoxidase. The model is able to simulate the kinetics of qE at low and high light intensities. The simulations suggest that the pH of the lumen, which activates qE, is not itself affected by qE. Our model provides a framework for testing hypothesized qE mechanisms and for assessing the role of qE in improving plant fitness in variable light intensity.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::897c30c53929553e28d8547929b75390 https://doi.org/10.1073/pnas.1211017109 Zobrazit plný text záznamu