Non-photochemical quenching

Bailey, S., N. Mann, C. Robinson, and D. J. Scanlan (2005). The occurrence of rapidly reversible non-photochemical quenching of chlorophyll a fluorescence in cyanobacteria. FEBS Lett 579(1) 275-280. Boulay, C., L. Abasova, C. Six, I. Vass, and D. Kirilovsky (2008a). Occurrence and function of the orange carotenoid protein in photoprotective mechanisms in various cyanobacteria. Biochim Biophys Acta 1777(10) 1344-1354. 

Karapetyan, N. V. (2007). Non-photochemical quenching of fluorescence in cyanobacteria. Biochemistry (Moscow) 72(10) 1127-1135. 

Kirilovsky, D. (2007). Photoprotection in cyanobacteria The orange carotenoid protein (OCP)-related non-photochemical-quenching mechanism. Photosynth Res 93 7-16. 

Muller, P., X.-P. Li, and K. Niyogi (2001). Non-photochemical quenching. A response to excess light energy. Plant Physiol 125 1558-1566. 

Horton, P., Wentworth, M., and Ruban, A. 2005. Control of the light harvesting function of chloroplast membranes The LHCII-aggregation model for non-photochemical quenching II. FEBS Lett. 579 4201 1206. 

Avital, S., V. Brumfeld, and S. Malkin. 2006. A micellar model system for the role of zeaxanthin in the non-photochemical quenching process of photosynthesis—Chlorophyll fluorescence quenching by xan-thophylls. Biochim. Biophys. Acta 1757 798-810. 

Holub, O., Seufferheld, M. J., Gohlke, C., Govindjee, G. J., Heiss, G. J. and Clegg, R. M. (2007). Fluorescence lifetime imaging microscopy of Chlamydomonas reinhardtii Non-photochemical quenching mutants and the effect of photosynthetic inhibitors on the slow chlorophyll fluorescence transients. J. Microsc. 226, 90-120. 

Humbeck K, Romer S and Senger H (1989) Evidence for an essential role of carotenoids in the assembly of an active photosystem 11. Planta 179 242-250 Hurry VM (1995) Non-photochemical quenching in xanthophyU cycle mutants of Arabidopsis and tobacco deficient in cytochrome B JF and ATPase activity. In Mathis P (ed) Photosynthesis From Light to Biosphere, pp 417-420. Kluwer Academic Publishers, Dordrecht Hurry V, Anderson JM, Chow WS and Osmond CB (1997) Accumulation of Zeaxanthin in absdsic acid-deficient mutants of Arabidopsis does not affect chlorophyll fluorescence quenching or sensitivity to photoinhibition in vivo. Plant Physiol 113 639-648... 

Chlamydomonas mutants have been isolated that are deficient either in violaxanthin de-epoxidase or zeaxanthin epoxidase. Using these mutants, it could be demonstrated that only part of the non-photochemical quenching observed in Chlamydomonas is dependent on the formation of zeaxanthin (Niyogi etal., 1997a). It will be interesting to see whether the absence of xanthophyll epoxidase or de-epoxidase products has an effect on the assembly of light-harvesting complexes in these mutants. 

Gilmore AM, Mohanty N and Yamamoto HY (1994) Epoxidation of zeaxanthin and antheraxanthin reverses non-photochemical quenching of Photosystem II chlorophyll a fluorescence in the presence of a trans-thylakoid ApH. FEBS Letts 350 271-274... 

III. Unanswered Questions Concerning the Roles of the Xanthophyll Cycle in Non-photochemical Quenching... 

Ruban AV, and Horton P (1995) Regulation of non-photochemical quenching of chlorophyll fluorescence in plants. Aust J Plant Physiol 22 21-30... 

Walters RG and Horton P (1993) Theoretical assessment of alternative mechanisms for non-photochemical quenching in barley leaves. Photosynth Res 27 121-133 Walters RG, Ruban AV and Horton P (1994) Light-harvesting complexes bound by dicyclohexylcarbodiimide during inhibition of protective energy dissipation. Eur J Biochem 226 1063-1069... 

Fig. 8. (a) The irradiance dependency of qg (O) and the quantum efficiency of electron transport by open Photosystem II reaction centres (excl ) (b) the irradiance dependency of the quantum efficiencies for de-excitation by the basal, constitutive pathway and the inducible (NPQ or non-photochemical quenching) pathway at each irradiance the sum of these de-excitation pathways and the quantum yield for Photosystem II electron transport is one. 

Yamamoto, H., Kato, H., Shinzaki, Y., Horiguchi, S., Shikanai, T., Hase, T., Endo, T., Nishioka, M., Makino, A., Tomizawa, K., and Miyake, C. (2006). Ferredoxin hmits cyclic electron flow around PSI (CEF-PSI) in higher plants-stimulation of CEF-PSI enhances non-photochemical quenching of Chi fluorescence in transplastomic tobacco. Plant Cell Physiol. 47, 1355-1371. 

The slow decrease of the fluorescence intensity at later times is termed non-photochemical quenching". Nonphotochemical quenching seems to be essential in protecting the plant from photodamage, or may even be a result of moderate photodamage. The processes that lead to nonphotochemical quenching are often referred to as photoinhibition". 

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