title: Purification and characterization of aminoimidazole ribonucleotide synthetase from Escherichia coli.
abstract: Aminoimidazole ribonucleotide (AIR) synthetase has been purified 15-fold to apparent homogeneity from Escherichia coli which contains a multicopy plasmid containing the purM, AIR synthetase, gene. The protein is a dimer composed of two identical subunits of Mr 38,500. The N-terminal sequence, amino acid composition, and steady-state kinetics of the protein have been determined. AIR synthetase has been shown to catalyze the transfer of the formyl oxygen of [18O]formylglycinamide ribonucleotide to Pi.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D019731:Carbon-Nitrogen Ligases; D004926:Escherichia coli / Q000201:enzymology*; D007700:Kinetics; D008025:Ligases / Q000302:isolation & purification* / Q000378:metabolism; D046911:Macromolecular Substances; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D010103:Oxygen Isotopes
chemical_list: D000596:Amino Acids; D046911:Macromolecular Substances; D010103:Oxygen Isotopes; D008025:Ligases; D019731:Carbon-Nitrogen Ligases; C022380:phosphoribosylaminoimidazole synthase