caa a22 4500 445889861 CHVBK 20180317145612.0 cr unu---uuuuu 170323e20110201xx s 000 0 eng 10.1007/s11120-010-9617-x doi (NATIONALLICENCE)springer-10.1007/s11120-010-9617-x Polyamines stimulate non-photochemical quenching of chlorophyll a fluorescence in Scenedesmus obliquus [Elektronische Daten] [Nikolaos Ioannidis, Liliana Sfichi-Duke, Kiriakos Kotzabasis] Polyamines (PAs) are small metabolites that are produced and oxidized in chloroplasts with an obscure mode of action. Recently, we showed that qE is stimulated by PAs in higher plants (Nicotiana tabacum) and in genetically modified plants with elevated thylakoid-associated PAs (Ioannidis and Kotzabasis Biochim Biophys Acta 1767:1371-1382, 2007; Ioannidis et al. Biochim Biophys Acta 1787:1215-1222, 2009). Here, we investigated further their quenching properties both in vivo in green algae and in vitro is isolated LHCII. In vivo spermine up-regulates NPQ in Scenedesums obliquus about 30%. In vitro putrescine—the obligatory metabolic precursor of PAs—has a marginal quenching effect, while spermidine and spermine exhibit strong quenching abilities in isolated LHCII up to 40%. Based on available 3D models of LHCII we report a special cavity of about 600Å3 and a near-by larger pocket in the trimeric LHCII that could be of importance for the stimulation of qE by amines. Springer Science+Business Media B.V., 2011 Energization quenching nationallicence Thylakoids nationallicence Photosystem nationallicence Amines nationallicence Protons nationallicence Chl : Chlorophyll nationallicence PA : Polyamine nationallicence Put : Putrescine nationallicence Spd : Spermidine nationallicence Spm : Spermine nationallicence NPQ : Non-photochemical quenching nationallicence qE : High energy quenching nationallicence LHC : Light-harvesting complex nationallicence PSII : Photosystem II nationallicence Ioannidis Nikolaos Department of Biology, University of Crete, P.O. Box 2208, 71409, Heraklion, Crete, Greece aut Sfichi-Duke Liliana Department of Biology, University of Crete, P.O. Box 2208, 71409, Heraklion, Crete, Greece aut Kotzabasis Kiriakos Department of Biology, University of Crete, P.O. Box 2208, 71409, Heraklion, Crete, Greece aut Photosynthesis Research Springer Netherlands 107/2(2011-02-01), 169-175 0166-8595 107:2<169 2011 107 11120 https://doi.org/10.1007/s11120-010-9617-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11120-010-9617-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ioannidis Nikolaos Department of Biology, University of Crete, P.O. Box 2208, 71409, Heraklion, Crete, Greece aut NATIONALLICENCE 700 1- Sfichi-Duke Liliana Department of Biology, University of Crete, P.O. Box 2208, 71409, Heraklion, Crete, Greece aut NATIONALLICENCE 700 1- Kotzabasis Kiriakos Department of Biology, University of Crete, P.O. Box 2208, 71409, Heraklion, Crete, Greece aut NATIONALLICENCE 773 0- Photosynthesis Research Springer Netherlands 107/2(2011-02-01), 169-175 0166-8595 107:2<169 2011 107 11120 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer