Light-generated nuclear quantum beats: a signature of photosynthesis

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 92; no. 17; pp. 7789 - 7793
• Main Authors: Weber, S. (University of Stuttgart, Stuttgart, Germany.), Ohmes, E, Thurnauer, M.C, Norris, J.R, Kothe, G
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 15-08-1995; National Acad Sciences; National Academy of Sciences
• Subjects: Acoustic spectra; Bacteria; Biochemistry; Biology; CYANOPHYTA; Electrons; ESPECTROSCOPIA ESR; FOTOSINTESIS; FOTOSISTEMAS; Lasers; Light; LUMIERE; LUZ; Magnetic fields; Magnetization; Microwaves; Nuclear spin; OXIRREDUCION; OXYDOREDUCTION; PHOTOSYNTHESE; Photosynthesis; PHOTOSYSTEME; Physics; SPECTROSCOPIE RSE; Synechococcus lividus; Tensors
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.92.17.7789

Light-induced radical pairs in deuterated and deuterated plus 15N-substituted Synechococcus lividus cyanobacteria have been studied by transient EPR following pulsed laser excitation. Nuclear quantum beats are observed in the transverse electron magnetization at lower temperatures. Model calculations for the time profiles, evaluated at the high-field emissive maximum of the spectrum, indicate assignment of these coherences to nitrogen nuclei in the primary donor. Thorough investigation of the nuclear modulation patterns can provide detailed information on the electronic structure of the primary donor, providing insight into the mechanism of the primary events of plant photosynthesis