CD spectroscopy provides evidence for excitonic interactions involving red‐shifted chlorophyll forms in photosystem I

FEBS Letters

Engelmann, E.¹  Jennings, R.C.¹  Garlaschi, F.M.¹  Tagliabue, T.¹  Zucchelli, G.¹  Karapetyan, N.V.² 

[1] Centro C.N.R. Biologia Cellulare e Molecolare delle Piante, Dipartimento di Biologia, Università di Milano, Via Celoria 26, 20133 Milan, Italy;A.N. Bakh Institute of Biochemistry, Russian Academy of Sciences, Leninsky Prospect, 33, 117071 Moscow, Russia

关键词: CD spectroscopy;    Excitonic interaction;    Photobleaching;    Red chlorophyll form;    PSII;    photosystem II;    PSI;    photosystem I;    Chl;    chlorophyll;   

DOI  :  10.1016/S0014-5793(01)02533-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Selective destruction of the strongly dichroic red-shifted chlorophyll form (C709 nm) in photosystem I (PSI) trimers from Spirulina, by either non-selective high intensity illumination (photobleaching) or incubation with low concentrations of Triton X-100 is accompanied by changes in the circular dichroism spectrum of the same amplitude and of opposite sign at 677 nm. The data are interpreted in terms of a dimeric chlorophyll structure with excitonic bands at these two wavelengths. Similar photobleaching experiments with PSI-200 from maize also suggest the presence of bulk antenna/red form excitonic interactions.

【 授权许可】

Unknown