Biochemistry 2002, 41, 4117-4126
4117
Electron Transfer from the Water Oxidizing Complex at Cryogenic Temperatures: The S1 to S2 Step† Jonathan H. A. Nugent,* Irine P. Muhiuddin, and Michael C. W. Evans Department of Biology, Darwin Building, UniVersity College London, Gower Street, London WC1E 6BT, U.K. ReceiVed June 25, 2001; ReVised Manuscript ReceiVed January 22, 2002
ABSTRACT: We report the detection of a “split” electron paramagnetic resonance (EPR) signal during illumination of dark-adapted (S1 state) oxygen-evolving photosystem II (PSII) membranes at
