title: Carboxyl-terminal processing protease for the D1 precursor protein: cloning and sequencing of the spinach cDNA.
abstract: A previous study has demonstrated that the carboxyl-terminal (C-terminal) processing protease in spinach for the D1 precursor protein (pDl) of the photosystem II reaction center is a monomeric protein of about 45 kDa. Based on the amino acid sequence data of the purified protease, a cDNA clone encoding the enzyme has been identified and sequenced, from a spinach green leaf cDNA library. In order to determine the 5' end of the transcript, the rapid amplification of cDNA end (5'-RACE) technique was applied. By these analyses, the full-length transcript was established to consist of 1906 nucleotides and a poly(A) tail, containing an open reading frame (ORF) corresponding to a protein with 539 amino acid residues. By comparing the amino acid sequence of the purified protease with that deduced from nucleotide sequence of the cDNA clones, the enzyme was shown to be furnished with an extra amino-terminal extension characteristic of both a transit peptide and a signal sequence. This suggests that the protease is synthesized in the cytosol and translocated into the lumenal space of thylakoids. The mature part of the enzyme consists of 389 amino acid residues and exhibits a significant sequence homology with two groups of proteins as demonstrated by a computer homology search, i.e. (1) the deduced sequence of a protein proposed to be the C-terminal processing protease for pD1 in Synechocystis sp. PCC 6803, based on genetic experiments and (2) proteases for C-terminal cleavage identified in Escherichia coli and Bartonella bacilliformis.
authors.affiliation: Division of Biological Regulation and Photobiology, National Institute for Basic Biology, Okazaki, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Inagaki
authors.forename: Y
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: H
authors.initials: H
authors.lastname: Mori
authors.forename: K
authors.initials: K
authors.lastname: Satoh
mesh_terms: D020418:Algal Proteins; D000595:Amino Acid Sequence; D001483:Base Sequence; D002268:Carboxypeptidases; D002451:Cell Compartmentation; D002736:Chloroplasts / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D010450:Endopeptidases / Q000235:genetics*; D015723:Gene Library; D008969:Molecular Sequence Data; D045322:Photosynthetic Reaction Center Complex Proteins / Q000378:metabolism*; D045332:Photosystem II Protein Complex; D043484:Proprotein Convertases; D011498:Protein Precursors / Q000235:genetics*; D011499:Protein Processing, Post-Translational; D021382:Protein Sorting Signals / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D018724:Spinacia oleracea / Q000201:enzymology / Q000235:genetics*
chemical_list: D020418:Algal Proteins; D018076:DNA, Complementary; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D011498:Protein Precursors; D021382:Protein Sorting Signals; D002268:Carboxypeptidases; D010450:Endopeptidases; D043484:Proprotein Convertases; C073491:photosystem II, D1 polypeptide carboxy-terminal processing protease