EXCITED-STATE STRUCTURE AND ENERGY-TRANSFER DYNAMICS OF 2 DIFFERENT PREPARATIONS OF THE REACTION CENTER OF PHOTOSYSTEM-II - A HOLE-BURNING STUDY

Two distinctly different preparations of the D1-D2-cytochrome 6-559 photosystem II reaction center (RC) complex are shown to exhibit very similar 4.2 K absorption and hole-burned spectra in glasses. Absorption profiles for P680 and the active pheophytin are fully characterized with the mean zero-point energy of P680*lying ≈25 cm-1 lower in energy than the Qy, state of the latter. Decay of the accessory chlorophyll and pheophytin Qy states due to energy transfer is shown to be about 3 orders of magnitude slower than in bacterial RC. © 1990 American Chemical Society.