title: PsbY, a novel manganese-binding, low-molecular-mass protein associated with photosystem II.
abstract: We describe two related manganese-binding polypeptides with L-arginine metabolizing enzyme activity that can be detected as distinct components (designated PsbY-A1 and PsbY-A2, previously called L-AME) in membranes containing Photosystem II (PS II) from spinach. The polypeptides are bitopic and appear to exist in a heterodimeric form, but only in the chlorophyll a/b lineage of plants. Both proteins are encoded in the nucleus. In spinach and in Arabidopsis thaliana they are both derived from a single-copy gene (psbY) that is translated into a precursor polyprotein of approximately 20 kDa. The processing of the polyprotein is complex and includes at least four cleavage steps. Both polypeptides are exposed N-terminally to the lumenal and C-terminally to the stromal face of the thylakoid membrane.
authors.affiliation: Biologie VIII: Zellphysiologie, Universität Bielefeld, Germany.
authors.forename: A E
authors.initials: AE
authors.lastname: Gau
authors.forename: H H
authors.initials: HH
authors.lastname: Thole
authors.forename: A
authors.initials: A
authors.lastname: Sokolenko
authors.forename: L
authors.initials: L
authors.lastname: Altschmied
authors.forename: R G
authors.initials: RG
authors.lastname: Hermann
authors.forename: E K
authors.initials: EK
authors.lastname: Pistorius
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D029681:Arabidopsis Proteins; D001120:Arginine / Q000378:metabolism; D001483:Base Sequence; D001692:Biological Transport; D019607:Brassicaceae / Q000235:genetics*; D002451:Cell Compartmentation; D002467:Cell Nucleus / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D019281:Dimerization; D019143:Evolution, Molecular; D018628:Gene Dosage; D015723:Gene Library; D008345:Manganese / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins; D011498:Protein Precursors / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D018724:Spinacia oleracea / Q000235:genetics; D014512:Ureohydrolases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D008565:Membrane Proteins; D010940:Plant Proteins; D011498:Protein Precursors; D008345:Manganese; D001120:Arginine; C492035:PSBY protein, Arabidopsis; C115697:PsbY protein, Spinacia oleracea; D014512:Ureohydrolases