Figure 1.

Isolation of PSII supercomplexes and its absorption and fluorescence emission spectra at 77 K. A, thylakoids membranes were isolated from low-light (20 μE m⁻² s⁻¹) and high-light (500 μE m⁻² s⁻¹) grown C. reinhardtii. For each lane, 2.0 μg of Chl of thylakoids membranes were subjected to immunoblotting analyses with antibodies against LHCSR3 and D1. B, the thylakoid membranes (250 μg of Chl) were solubilized with dodecyl α-maltoside and loaded on SDG. Four bands were identified as LHCII monomers, LHCII trimers, PSI supercomplexes, and PSII supercomplexes, as indicated. C, absorption spectra of PSII supercomplexes at pH 7.5 were obtained from reflectance spectra of frozen samples in NMR glass tubes at 77 K and normalized at the maximum peak. D, fluorescence emission spectra of PSII supercomplexes at pH 7.5 were obtained by excitation at 440 nm and normalized at the maximum peak.