Three-dimensional structure of the free radical protein of ribonucleotide reductase.
The enzyme ribonucleotide reductase furnishes precursors for the DNA synthesis of all living cells. One of its constituents, the free radical protein, has an unusual alpha-helical structure. There are two iron centres that are about 25 A apart in the dimeric molecule. Tyrosine 122, which harbours the stable free radical necessary for the activity of ribonucleotide reductase, is buried inside the protein and is located 5 A from the closest iron atom.
Department of Molecular Biology, Swedish University of Agricultural Sciences, Uppsala.
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D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D003460:Crystallization; D004926:Escherichia coli / Q000032:analysis*; D005609:Free Radicals; D006422:Hemerythrin; D007501:Iron; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011487:Protein Conformation; D011506:Proteins; D012264:Ribonucleotide Reductases; D012689:Sequence Homology, Nucleic Acid; D014443:Tyrosine
D005609:Free Radicals; D006422:Hemerythrin; D046911:Macromolecular Substances; D011506:Proteins; D014443:Tyrosine; D007501:Iron; D012264:Ribonucleotide Reductases