title: Characterization of a spinach photosystem II core preparation isolated by a simplified method.
abstract: A photosystem II core complex from spinach exhibiting high rates of electron transport was obtained rapidly and in high yield by treatment of a Tris-extracted, O2-evolving photosystem II preparation with the detergent dodecyl-beta-D-maltoside. The core complex was essentially free of light-harvesting chlorophyll-protein and photosystem I polypeptides, and was highly enriched in the polypeptides associated with the photosystem II reaction center (45 and 49 kDa), cytochrome b559, and three polypeptides in the region 32-34 kDa. The photosystem II core complex contained two chlorophyll-proteins which had a slightly higher apparent molecular mass than CPa-1 and CPa-2. Additionally, a high-molecular-mass chlorophyll-protein complex termed CPa* was observed, which exhibited a low fluorescence yield when illuminated with ultraviolet light. This observation suggests that CPa* contains a functionally efficient quencher of chlorophyll fluorescence, possibly P680.
mesh_terms: D002734:Chlorophyll / Q000032:analysis / Q000302:isolation & purification*; D045342:Light-Harvesting Protein Complexes; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D010940:Plant Proteins / Q000302:isolation & purification*; D010944:Plants / Q000032:analysis*; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry
chemical_list: D045342:Light-Harvesting Protein Complexes; D010446:Peptide Fragments; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D002734:Chlorophyll