Roy Esha, Gast Peter, van Gorkom Hans J, de Groot Huub J M, Jeschke Gunnar, Matysik Jörg
Contribution from the Leiden Institute of Chemistry, Gorlaeus Laboratoria, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
J Am Chem Soc. 2004 Oct 13;126(40):12819-26. doi: 10.1021/ja048051+.
Photochemically induced dynamic nuclear polarization (photo-CIDNP) has been observed in photosystem I of spinach by (13)C magic angle spinning solid-state NMR under continuous illumination with white light. An almost complete set of chemical shifts of the aromatic ring carbons of a single Chl a molecule has been obtained which is assigned to the P2-cofactor of the primary electron donor P700. Since all light-induced (13)C NMR signals appear to be emissive, a predominance of the three-spin mixing mechanism over the differential decay mechanism is proposed. The origin of the strong contribution of the three-spin mixing mechanism and the differences with photosystem II are discussed.
在白光持续照射下，通过¹³C魔角旋转固态核磁共振技术，在菠菜光系统I中观察到了光化学诱导动态核极化（光CIDNP）现象。已获得单个叶绿素a分子芳香环碳的几乎完整的化学位移集，这些化学位移被指定给初级电子供体P700的P2辅因子。由于所有光诱导的¹³C NMR信号似乎都是发射性的，因此提出三自旋混合机制比微分衰减机制占主导地位。讨论了三自旋混合机制的强大贡献的起源以及与光系统II的差异。
