Abstract
State transition is a short-term acclimation to balance excitation ratio between Photosystem I (PSI) and II (PSII) in oxygenic photosynthetic organisms. When PSII was preferentially excited (state 2), a part of light harvesting complex II (LHCII) migrates from PSII to PSI, forming PSI-LHCI/II supercomplex. We have already reported the isolation of this supercomplex containing CP26, CP29, and LhcbM5 from Chlamydomonas cells in state 2. Here we report the effect of ionic strength on association of LHCIIs with PSI-LHCI complex in order to analyze pigment composition of the PSI-LHCI/II supercomplex. We found that LHCIIs are detached from the supercomplex in a high ionic strength, which can be used to dissociate and purify LHCIIs under a mild condition. We will also report pigment contents of LHCIIs bound to PSI complex.
