Abstract
Okinawa mozuku (Cladosiphon okamuranus Tokida) is an original strain of brown algae in Okinawa. The super large scale culture of the discoid germiling of this strain was established. The discoid germiling is a spherical microorganism having diameter of 40 - 200 micro meter, and it is very useful to isolate photosynthetic membrane in mild conditions. In brown algal photosynthesis, the major antenna pigment-protein complexes, fucoxanthin-chlorophyll a/c protein (FCP) absorb the photo energy and transfer it to both photosystems I and II. The biochemical and spectroscopic properties of brown algal FCP have been relatively less studied. We have been isolate and purified the FCP from the Okinawa mozuku. The FCP found to exist as a homo- or hetero-trimer with two subunits showing molecular weight of 17.5 and 18.2 kD. We directly determined, for the first time, both chlorophyll (Chl) c1 and c2 bound equally to the FCP. The pigment stoichiometry was also determined by using 1H-NMR as fucoxanthin : Chl a : Chl c1 : Chl c2 = 5.5 : 4.5 : 1.1 : 1.0. In this study, we applied the femtosecond time-resolved spectroscopy to clarify the dynamics of the excitation energy transfer in the FCP.
