title: A novel subfamily of monomeric inorganic pyrophosphatases in photosynthetic eukaryotes.
abstract: Two sPPases (soluble inorganic pyrophosphatases, EC 3.6.1.1) have been isolated from the microalga Chlamydomonas reinhardtii. Both are monomeric proteins of organellar localization, the chloroplastic sPPase I [Cr (Ch. reinhardtii)-sPPase I, 30 kDa] is a major isoform and slightly larger protein than the mitochondrial sPPase II (Cr-sPPase II, 24 kDa). They are members of sPPase family I and are encoded by two different cDNAs, as demonstrated by peptide mass fingerprint analysis. Molecular phylogenetic analyses indicated that Cr-sPPase I is closely related to other eukaryotic sPPases, whereas Cr-sPPase II resembles its prokaryotic counterparts. Chloroplastic sPPase I may have replaced a cyanobacterial ancestor very early during plastid evolution. Cr-sPPase II orthologues are found in members of the green photosynthetic lineage, but not in animals or fungi. These two sPPases from photosynthetic eukaryotes are novel monomeric family I sPPases with different molecular phylogenies and cellular localizations.
authors.affiliation: Instituto de Bioquímica Vegetal y Fotosíntesis, CSIC-Universidad de Sevilla, Centro de Investigaciones Científicas Isla de la Cartuja, 41092-Sevilla, Spain. mrgomez@stanford.edu
authors.forename: María R
authors.initials: MR
authors.lastname: Gómez-García
authors.forename: Manuel
authors.initials: M
authors.lastname: Losada
authors.forename: Aurelio
authors.initials: A
authors.lastname: Serrano
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000201:enzymology; D016825:Chlamydomonas reinhardtii / Q000201:enzymology* / Q000378:metabolism; D002736:Chloroplasts / Q000201:enzymology; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D043564:Inorganic Pyrophosphatase / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D010788:Photosynthesis; D010802:Phylogeny; D011401:Promoter Regions, Genetic / Q000235:genetics; D020033:Protein Isoforms; D021381:Protein Transport; D016415:Sequence Alignment
chemical_list: D018076:DNA, Complementary; D020033:Protein Isoforms; D043564:Inorganic Pyrophosphatase