Energy transfer kinetics of phycoerythrocyanin trimer from cyanobacterium Anabaena variabilis (II)

The excitation energy transfer processes in trimeric PEC have been studied by using steady-state and time-resolved fluorescence spectra techniques in detail. The results indicate that the energy transfer processes should take place between α84-PVB and β84-or β155-PCB chromophores with the time constants 34.7 ps and 175–200 ps individually; in contrast with monomeric PEC, from time-resolved fluorescence anisotropic spectrum technique, the decay constant of 45 ps which was assigned to the energy transfer time among three β84-PCB chromophores was observed and the energy levels of β84-and/or β155-PCB chromophores were confirmed to turn over in trimeric PEC. Project supported by the National Natural Science Foundation of China (Grant No. 39670065).