Abstract
In photosynthetic-bacterial antenna complexes(LHC), the
photo energy is transferred from the peripheral LH2 to the
LH1 which surround the reaction-center (RC)and finaly to
the RC. A Carotenoid(Car)in the RC dissipate harmful
triplet bacteriochlorophyll(T1 BChl)via triplet-
energy transfer. Additionally, the LH1 in the RC-LH1(Core)
complex may restrict the energy transfer to the RC to
prevent T1 BChl generation. Now we focused on
the Core, which is a primitive photosynthetic-unit, to
investigate the excited-state dynamics of the pigments. The
Core was isolated from Rhodobacter sphaeroides G1C
and confirmed their purity by SDS-PAGE. Time-resolved
absorption spectra of the Core show that triplet-excited
state appears more obvious and the Qy state of BChl which
appears as a result of the energy transfer of
Car→BChl is less populated than those in the LH2.
These phenomena can be explained as a reduction of energy
transferred to the oxidized RC.
