INFLUENCE OF THE MEMBRANE ENVIRONMENT ON VIBRATIONAL MOTIONS IN REACTION CENTERS OF RHODOBACTER-SPHAEROIDES

A comparison is made between the femtosecond oscillatory kinetics in m embranes and in detergent-solubilized reaction centres of the antenna- deficient RCO1 mutant of Rhodobacter sphaeroides. The main features ar e very similar, both at room temperature and at 10 K, but the dampenin g of the oscillations occurs somewhat more slowly in membranes. The re sults indicate that the observed coherent vibrations involve the prote in matrix surrounding the chromophores.