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(2005). https://pubmed.ncbi.nlm.nih.gov/16373698/ DOI: 10.1158/1535-7163.mct-05-0273","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Ribonucleotide reductase small subunits","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"3d1c5dbf-dc12-5953-84c3-da0c307a43c3","evidence_kind":"source_excerpt","locator":"Lines 1174-1185","start_line":1174,"end_line":1185,"excerpt":"### iron-rrm2-iron-radical\nHuman RRM2 radical-center tyrosine mutations abolished the detectable stable radical and ribonucleotide-reductase activity in the tested assays.\nCondition category: normal\nnutrient_topic: Iron research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: DNA building-block synthesis needs a functioning iron/radical enzyme system.\norganism: Human RRM2 and RRM2B proteins\ntissue_or_cell_type: Ribonucleotide reductase small subunits\nexperimental_model: Mutagenesis, EPR and catalytic assays\nlimitations: Purified enzyme mechanisms; no recommendation to increase dietary iron for DNA synthesis.\nexposure: Conserved tyrosine mutations around the diiron center\nevidence_span: {\"source_cache\": \"artifacts/iron-research/16373698.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"0d3e9b3d6c8961f94af38195eab5b0b3180c321da1c7ca75ae956036a60b16cc\", \"start_char\": 0, \"end_char\": 1165, \"text_sha256\": \"0d3e9b3d6c8961f94af38195eab5b0b3180c321da1c7ca75ae956036a60b16cc\"}\n[iron-p16373698] A dityrosyl-diiron radical cofactor center is essential for human ribonucleotide reductases. 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