title: Effects of trypsin and calcium chloride on signal IIs in oxygen-evolving PS II preparations.
abstract: Photosystem II oxygen-evolving preparations exhibited a reversible loss of signal IIs hyperfine structure when treated with 1.0 M CaCl2. A progressive irreversible loss of hyperfine structure was observed upon trypsin treatment of these preparations. These treatments appear to alter the environment of the radical responsible for signal IIs. Gel electrophoresis of trypsin-treated photosystem II preparations indicates that three polypeptides (45, 32-34, and 26 kDa) are altered with the same kinetics as observed for the trypsin-induced loss of signal IIs. Two of these polypeptides (45 and 32-34 kDa) are core components of photosystem II.
mesh_terms: D002122:Calcium Chloride / Q000494:pharmacology*; D002734:Chlorophyll / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D004591:Electrophoresis, Polyacrylamide Gel; D045342:Light-Harvesting Protein Complexes; D008970:Molecular Weight; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins / Q000378:metabolism*; D014357:Trypsin / Q000378:metabolism*
chemical_list: D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D002734:Chlorophyll; D014357:Trypsin; D002122:Calcium Chloride