An electron paramagnetic resonance investigation of the electron transfer reactions in the chlorophyll d containing photosystem I of Acaryochloris marina.
Electron paramagnetic resonance (EPR) spectroscopy reveals functional and structural similarities between the reaction centres of the chlorophyll d-binding photosystem I (PS I) and chlorophyll a-binding PS I. Continuous wave EPR spectrometry at 12K identifies iron-sulphur centres as terminal electron acceptors of chlorophyll d-binding PS I. A transient light-induced electron spin echo (ESE) signal indicates the presence of a quinone as the secondary electron acceptor (Q) between P(740)(+) and the iron-sulphur centres. The distance between P(740)(+) and Q(-) was estimated within point-dipole approximation as 25.23+/-0.05A, by the analysis of the electron spin echo envelope modulation.
Santabarbara
Stefano
S
Department of Biology, University College London, Gower Street, London WC1E 6BT, UK. s.santabarbara@qmul.ac.uk <s.santabarbara@qmul.ac.uk>
Chen
Min
M
Larkum
Anthony W D
AW
Evans
Michael C W
MC
D002734:Chlorophyll / Q000737:chemistry* / Q000528:radiation effects; D003080:Cold Temperature; D000458:Cyanobacteria / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D004579:Electron Transport; D007700:Kinetics; D008027:Light; D045331:Photosystem I Protein Complex / Q000737:chemistry* / Q000528:radiation effects
D045331:Photosystem I Protein Complex; D002734:Chlorophyll; C107509:chlorophyll d