title: Photo-CIDNP solid-state NMR on photosystems I and II:what makes P680 special?
abstract: The origin of the extraordinary high redox potential of P680, the primary electron donor of Photosystem II, is still unknown. Photochemically induced dynamic nuclear polarisation (photo-CIDNP) 13C magic-angle spinning (MAS) NMR is a powerful method to study primary electron donors. In order to reveal the electronic structure of P680, we compare new photo-CIDNP MAS NMR data of Photosystem II to those of Photosystem I. The comparison reveals that the electronic structure of the P680 radical cation is a Chl a cofactor with strong matrix interaction, while the radical cation of P700, the primary electron donor of Photosystem I, appears to be a Chl a cofactor which is essentially undisturbed. Possible forms of cofactor-matrix interactions are discussed.
authors.affiliation: Gorlaeus Laboratoria, Leiden Institute of Chemistry, Einsteinweg 55, P.O. Box 9502, 2300 RA, Leiden, The Netherlands.
authors.forename: Anna
authors.initials: A
authors.lastname: Diller
authors.lastname: Alia
authors.forename: Esha
authors.initials: E
authors.lastname: Roy
authors.forename: Peter
authors.initials: P
authors.lastname: Gast
authors.forename: Hans J
authors.initials: HJ
authors.lastname: van Gorkom
authors.forename: Jan
authors.initials: J
authors.lastname: Zaanen
authors.forename: Huub J M
authors.initials: HJ
authors.lastname: de Groot
authors.forename: Clemens
authors.initials: C
authors.lastname: Glaubitz
authors.forename: Jörg
authors.initials: J
authors.lastname: Matysik
mesh_terms: D004579:Electron Transport; D004735:Energy Transfer; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation / Q000379:methods*; D045331:Photosystem I Protein Complex / Q000737:chemistry* / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000737:chemistry* / Q000378:metabolism
chemical_list: D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex