Abstract
We succeeded in isolation of PSII particles retaining high oxygen-evolving activity from a marine diatom, Chaetoceros gracilis (B.B.A. in press). The PSII particles contained 229 Chl a/2 pheophytin. The PSII core complex consisted of CP47, CP43 and D1/D2 core which was prepared by Blue-Native PAGE also contained about 80 Chl a, 14 β-carotene and 3 diadinoxanthin per 2 pheophytin. Thus, the antenna size of the diatom PSII was significantly larger than those of the other organisms. In this study, we attempted to separate CP47, CP43 and D1/D2 core from the PSII particles and analyze pigment compositions in these polypeptides. The diatom PSII particles solubilized with HTG were subjected to DEAE TOYOPEARL and eluted by circulation with buffers containing HTG and various NaCl concentrations. Consequently, we partially purified CP47, CP43, D1/D2 core and will report about pigment analysis of their polypeptides.
