title: A cDNA clone from Arabidopsis thaliana encoding plastidic ferredoxin:sulfite reductase.
abstract: A cDNA with an open reading frame of 1929 bp (termed sir) was isolated from a lambda ZapII library of Arabidopsis thaliana leaf tissue. The polypeptide sequence deduced from the cDNA is homologous to the ferredoxin-dependent sulfite reductase (EC 1.8.7.1) from Synechococcus PCC7942 and distantly related to the hemoprotein subunit of Escherichia coli NADPH-dependent sulfite reductase (EC 1.8.1.2). A molecular mass of 71.98 kDa can be predicted for a ferredoxin sulfite reductase from A. thaliana. The polypeptide consists of 642 amino acids including a transit peptide of 66 residues (6.72 kDa) that is assumed to direct the protein into the plastid. For expression and enzymatic characterization of a putative A. thaliana ferredoxin sulfite reductase, the DNA of the transit peptide was deleted by a PCR method. The truncated cDNA clone was expressed as his-tag fusion protein. The modified gene product was enzymatically inactive but specific cross-reaction with polyclonal antibodies against ferredoxin sulfite reductase from Synechococcus is seen as confirmation of its identity as higher plant ferredoxin sulfite reductase.
authors.affiliation: Faculty of Biology, Ruhr University Bochum, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Brühl
authors.forename: T
authors.initials: T
authors.lastname: Haverkamp
authors.forename: G
authors.initials: G
authors.lastname: Gisselmann
authors.forename: J D
authors.initials: JD
authors.lastname: Schwenn
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics*; D029681:Arabidopsis Proteins; D001483:Base Sequence; D000458:Cyanobacteria / Q000201:enzymology; D018076:DNA, Complementary / Q000302:isolation & purification*; D004926:Escherichia coli / Q000201:enzymology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000737:chemistry / Q000235:genetics*; D018087:Plastids / Q000201:enzymology* / Q000235:genetics*; D017385:Sequence Homology; D050889:Sulfite Reductase (Ferredoxin); D050864:Sulfite Reductase (NADPH)
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D050862:Oxidoreductases Acting on Sulfur Group Donors; D050864:Sulfite Reductase (NADPH); C494314:sulfite reductase (NADPH), E coli; C488954:SIR protein, Arabidopsis; D050889:Sulfite Reductase (Ferredoxin)