De Groot, Alex and Evelo, Rob and Hoff, Arnold J. and De Beer, Ron
Electron spin echo envelope modulation (ESEEM) spectroscopy of the triplet state of the primary donor of 14N and 15N bacterial photosynthetic reaction centers and of 14N and 15N bacteriochlorophyll a.
In: Chemical Physics Letters, Vol. 118, No. 1: pp. 48-54
An electron spin echo envelope modulation frequency analysis is performed on the triplet state of the primary electron donor (P-860) in 14N reaction centers of the photosynthetic bacterium Rhodopseudomonas sphaeroides R26 and 15N-enriched reaction centers of Rhodopseudomonas sphaeroides 2.4.1, and of the triplet state of 14N or 15N bacteriochlorophyll a in vitro. The hyperfine previous termcouplingnext term constants for 15N 3P-860 are 1.42, 1.74 and 2.04 MHz. The triplet state of the primary donor in bacterial photosynthesis is, on a timescale of a few MHz, delocalized over the two bacteriochlorophyll a molecules making up P-860.