title: Flavodoxin is required for the activation of the anaerobic ribonucleotide reductase.
abstract: The inactive anaerobic ribonucleotide reductase from Escherichia coli is transformed by a multienzyme system and S-adenosylmethionine + NADPH into a radical protein that is enzymatically active. One of the activating enzyme components was earlier shown to be ferredoxin (flavodoxin):NADP+ reductase. Here we present evidence that flavodoxin, but not ferredoxin, also is a component of the system. Light reduced deazaflavin can substitute for the flavodoxin system. An additional unidentified low-molecular weight component further stimulates the reaction.
authors.affiliation: Department of Biochemistry 1, Karolinska Institute, Stockholm, Sweden.
authors.forename: V
authors.initials: V
authors.lastname: Bianchi
authors.forename: R
authors.initials: R
authors.lastname: Eliasson
authors.forename: M
authors.initials: M
authors.lastname: Fontecave
authors.forename: E
authors.initials: E
authors.lastname: Mulliez
authors.forename: D M
authors.initials: DM
authors.lastname: Hoover
authors.forename: R G
authors.initials: RG
authors.lastname: Matthews
authors.forename: P
authors.initials: P
authors.lastname: Reichard
mesh_terms: D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase / Q000378:metabolism; D000693:Anaerobiosis; D001483:Base Sequence; D002850:Chromatography, Gel; D003001:Cloning, Molecular; D017931:DNA Primers; D004789:Enzyme Activation; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D005418:Flavodoxin / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D005798:Genes, Bacterial; D007700:Kinetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism; D015183:Restriction Mapping; D012264:Ribonucleotide Reductases / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D005418:Flavodoxin; D011994:Recombinant Proteins; D012264:Ribonucleotide Reductases; D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase