Abstract
We have reported that several small subunits are involved in the stabilization of the dimeric form of Photosystem II (PSII) complex. In this study we investigated the stability of the PSII dimer by blue-native PAGE. Thylakoid membranes prepared from Thermosynechococcus elongatus BP-1 were solubilized with various concentrations of n-dodecyl-β-D-maltopyranoside (DM). It was found that the recovery of the PSII monomer was high at low concentrations of DM, but was reduced at high concentrations. Concomitantly, higher recovery of the PSII dimer was obtained at high concentrations of DM. These results were confirmed by two-dimensional PAGE. Apparently, there was no significant difference in protein composition between the monomeric and dimeric PSII. These results suggest that dimerization of the PSII complex can be induced by action of DM. We will discuss the intrinsic form and interconversion of the PSII complexes in vivo.
