A break-through came from NSFC sponsored research work in photosynthesis of membrane protein: in particular, the research in the crystal structure of the light harvesting protein complex, LHC-Ⅱ.
Steady-state and time-resolved fluo- rescence spectroscopies have been used to study the excited state properties of Chl a in different ag- gregation forms of light-harvesting complex II (LHC II) from an intertidal gr...Steady-state and time-resolved fluo- rescence spectroscopies have been used to study the excited state properties of Chl a in different ag- gregation forms of light-harvesting complex II (LHC II) from an intertidal green alga, Bryopsis corticulans, i.e. LHC II monomer, trimer and oligomer. When either Chl a or Chl b was selectively excited, the observed decrease in Chl a fluorescence in the oligomer is proved to be caused mainly by the fast fluorescence quenching among Chl a molecules, rather than by the decrease in Chl b-to-Chl a singlet excitation transfer efficiency. Analyses of the picosecond time-resolved fluorescence kinetics identified two exponential de- cay components in all of the three forms of LHC II: a longer-lived component (4.1―4.7 ns) originating from fluorescence emission of Chl a, and a shorter-lived one (135―540 ps) from the rapid equilibration of singlet excitation among Chl a molecules. The time constant of excitation equilibration is 135 ps in oli- gomer, 520 ps in trimer and 540 ps in monomer. These results imply that LHC II in oligomer form is inherently able to quench Chl a excitation, a mecha- nism which may be related to the photoprotection of PS II via changing the degree of LHC II aggregation in Bryopsis corticulans.展开更多
THE photosystem Ⅱ light-harvesting chlorophyll a/b protein complex (LHC Ⅱ) is a kind of integral membrane protein complex in the thylakoid membranes of chloroplasts from higher plants and green algae, and its most i...THE photosystem Ⅱ light-harvesting chlorophyll a/b protein complex (LHC Ⅱ) is a kind of integral membrane protein complex in the thylakoid membranes of chloroplasts from higher plants and green algae, and its most important biological function is light harvesting and展开更多
文摘A break-through came from NSFC sponsored research work in photosynthesis of membrane protein: in particular, the research in the crystal structure of the light harvesting protein complex, LHC-Ⅱ.
基金This work was supported by the National Natural Science Foundation of China(Grant No.20273077)the Knowledge Innovation Program of Chinese Academy of Sciences(Grant No.KSCX2-SW-130).
文摘Steady-state and time-resolved fluo- rescence spectroscopies have been used to study the excited state properties of Chl a in different ag- gregation forms of light-harvesting complex II (LHC II) from an intertidal green alga, Bryopsis corticulans, i.e. LHC II monomer, trimer and oligomer. When either Chl a or Chl b was selectively excited, the observed decrease in Chl a fluorescence in the oligomer is proved to be caused mainly by the fast fluorescence quenching among Chl a molecules, rather than by the decrease in Chl b-to-Chl a singlet excitation transfer efficiency. Analyses of the picosecond time-resolved fluorescence kinetics identified two exponential de- cay components in all of the three forms of LHC II: a longer-lived component (4.1―4.7 ns) originating from fluorescence emission of Chl a, and a shorter-lived one (135―540 ps) from the rapid equilibration of singlet excitation among Chl a molecules. The time constant of excitation equilibration is 135 ps in oli- gomer, 520 ps in trimer and 540 ps in monomer. These results imply that LHC II in oligomer form is inherently able to quench Chl a excitation, a mecha- nism which may be related to the photoprotection of PS II via changing the degree of LHC II aggregation in Bryopsis corticulans.
文摘THE photosystem Ⅱ light-harvesting chlorophyll a/b protein complex (LHC Ⅱ) is a kind of integral membrane protein complex in the thylakoid membranes of chloroplasts from higher plants and green algae, and its most important biological function is light harvesting and
