A sequential two-step proteolytic process in the carboxyl-terminal truncation of precursor D1 protein in Synechocystis sp. PCC6803.
The D1 protein of photosystem II is synthesized in precursor with a carboxyl-terminal extension. Interestingly, there is quite a range in chain length of the extension, which roughly depends upon the class of organisms. In cyanobacteria, e.g. in Synechocystis sp. PCC6803, the extension consists of 16 amino acid residues, seven residues longer than its counterpart in higher plants. In this study, we examined the D1 processing in Synechocystis sp. PCC6803 by pulse-chase experiments and detected a proteolytic intermediate of this process. This finding suggests that the elongated extension in this organism is excised with a sequential two-step proteolysis, which differs markedly from the manner observed in higher plants.
Inagaki
N
N
Photosynthesis Laboratory, Plant Physiology Department, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan. ninagaki@nias.affrc.go.jp
Yamamoto
Y
Y
Satoh
K
K
D020418:Algal Proteins; D000595:Amino Acid Sequence; D002268:Carboxypeptidases; D000458:Cyanobacteria / Q000378:metabolism*; D010450:Endopeptidases / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D010449:Peptide Mapping; D045322:Photosynthetic Reaction Center Complex Proteins / Q000378:metabolism*; D045332:Photosystem II Protein Complex; D043484:Proprotein Convertases; D011498:Protein Precursors / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D013045:Species Specificity; D018724:Spinacia oleracea
D020418:Algal Proteins; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D011498:Protein Precursors; C422369:photosystem II, psbA subunit; D002268:Carboxypeptidases; D010450:Endopeptidases; D043484:Proprotein Convertases; C073491:photosystem II, D1 polypeptide carboxy-terminal processing protease