Component

Ribonucleotide reductase tyrosyl radical cofactor

Ribonucleotide reductase tyrosyl radical cofactor. Species, exposure and limitations are retained in each linked claim.

3 recorded relationships. Experimental role, claim status and evidence remain attached to each record.

Read recorded mechanisms Open recursive mind map

How nutrients influence it

Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.

How nutrients reach it in more than one step

Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.

Tracing routes…

What it does

Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.

Recorded relationships

What acts on it

  1. Intracellular iron chelation removed the ribonucleotide-reductase tyrosyl radical, with depletion and regeneration kinetics depending on the chelator.

    Cellular labile iron pool → Ribonucleotide reductase tyrosyl radical cofactor source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/iron-research/8702762.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ceb70db961d5ae6f975c9edf1df28c495811a38189831240b8e3e61530b3a7f0", "start_char": 0, "end_char": 1525, "text_sha256": "ceb70db961d5ae6f975c9edf1df28c495811a38189831240b8e3e61530b3a7f0"}
    experimental_model
    Intracellular chelation with simultaneous EPR measurements
    exposure
    Hydroxypyridinone versus desferrioxamine chelation and washout
    limitations
    Pharmacological cell experiment; radical loss is not a direct clinical measure of nutritional iron deficiency.
    nutrient_topic
    Iron research collection; topical membership is not evidence of a direct dietary effect. · Iron
    organism
    Human leukemia K562 cells
    plain_language
    Iron locked away by a chelator was not equally available to maintain the DNA-synthesis enzyme.
    primary_references
    [iron-p8702762] The relationship of intracellular iron chelation to the inhibition and regeneration of human ribonucleotide reductase. (1996). https://pubmed.ncbi.nlm.nih.gov/8702762/ DOI: 10.1074/jbc.271.34.20291
    tissue_or_cell_type
    Intracellular iron pool and ribonucleotide reductase

    Iron: absorption, trafficking, iron-dependent enzymes and nutrient interactions (2026-09-17) · lines 1200–1211

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Intracellular chelation with simultaneous EPR measurements · source_derived_draft · unverified_draft

    ### iron-chelation-rr Intracellular iron chelation removed the ribonucleotide-reductase tyrosyl radical, with depletion and regeneration kinetics depending on the chelator. Condition category: normal nutrient_topic: Iron research collection; topical membership is not evidence of a direct dietary effect. plain_language: Iron locked away by a chelator was not equally available to maintain the DNA-synthesis enzyme. organism: Human leukemia K562 cells tissue_or_cell_type: Intracellular iron pool and ribonucleotide reductase experimental_model: Intracellular chelation with simultaneous EPR measurements limitations: Pharmacological cell experiment; radical loss is not a direct clinical measure of nutritional iron deficiency. exposure: Hydroxypyridinone versus desferrioxamine chelation and washout evidence_span: {"source_cache": "artifacts/iron-research/8702762.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ceb70db961d5ae6f975c9edf1df28c495811a38189831240b8e3e61530b3a7f0", "start_char": 0, "end_char": 1525, "text_sha256": "ceb70db961d5ae6f975c9edf1df28c495811a38189831240b8e3e61530b3a7f0"} [iron-p8702762] The relationship of intracellular iron chelation to the inhibition and regeneration of human ribonucleotide reductase. (1996). https://pubmed.ncbi.nlm.nih.gov/8702762/ DOI: 10.1074/jbc.271.34.20291
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Human RRM2 radical-center tyrosine mutations abolished the detectable stable radical and ribonucleotide-reductase activity in the tested assays.

    Human ribonucleotide reductase small subunit RRM2 → Deoxyribonucleotide synthesis source_derived_draftungraded
    Experimental context and source evidence
    evidence_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"}
    experimental_model
    Mutagenesis, EPR and catalytic assays
    exposure
    Conserved tyrosine mutations around the diiron center
    limitations
    Purified enzyme mechanisms; no recommendation to increase dietary iron for DNA synthesis.
    nutrient_topic
    Iron research collection; topical membership is not evidence of a direct dietary effect. · Iron
    organism
    Human RRM2 and RRM2B proteins
    plain_language
    DNA building-block synthesis needs a functioning iron/radical enzyme system.
    primary_references
    [iron-p16373698] A dityrosyl-diiron radical cofactor center is essential for human ribonucleotide reductases. (2005). https://pubmed.ncbi.nlm.nih.gov/16373698/ DOI: 10.1158/1535-7163.mct-05-0273
    tissue_or_cell_type
    Ribonucleotide reductase small subunits

    Iron: absorption, trafficking, iron-dependent enzymes and nutrient interactions (2026-09-17) · lines 1174–1185

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Mutagenesis, EPR and catalytic assays · source_derived_draft · unverified_draft

    ### iron-rrm2-iron-radical Human RRM2 radical-center tyrosine mutations abolished the detectable stable radical and ribonucleotide-reductase activity in the tested assays. Condition category: normal nutrient_topic: Iron research collection; topical membership is not evidence of a direct dietary effect. plain_language: DNA building-block synthesis needs a functioning iron/radical enzyme system. organism: Human RRM2 and RRM2B proteins tissue_or_cell_type: Ribonucleotide reductase small subunits experimental_model: Mutagenesis, EPR and catalytic assays limitations: Purified enzyme mechanisms; no recommendation to increase dietary iron for DNA synthesis. exposure: Conserved tyrosine mutations around the diiron center evidence_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"} [iron-p16373698] A dityrosyl-diiron radical cofactor center is essential for human ribonucleotide reductases. (2005). https://pubmed.ncbi.nlm.nih.gov/16373698/ DOI: 10.1158/1535-7163.mct-05-0273
    Complete structured claim and evidence

  2. The corresponding conserved-tyrosine perturbation also disabled the radical and catalytic activity of the human p53R2/RRM2B system.

    Human p53-inducible ribonucleotide reductase small subunit / RRM2B → Deoxyribonucleotide synthesis source_derived_draftungraded
    Experimental context and source evidence
    evidence_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"}
    experimental_model
    Mutagenesis, EPR and catalytic assays
    exposure
    Conserved tyrosine mutations around the diiron center
    limitations
    Purified enzyme mechanisms; no recommendation to increase dietary iron for DNA synthesis.
    nutrient_topic
    Iron research collection; topical membership is not evidence of a direct dietary effect. · Iron
    organism
    Human RRM2 and RRM2B proteins
    plain_language
    The related small subunit is recorded separately so its role is not lost inside a generic enzyme label.
    primary_references
    [iron-p16373698] A dityrosyl-diiron radical cofactor center is essential for human ribonucleotide reductases. (2005). https://pubmed.ncbi.nlm.nih.gov/16373698/ DOI: 10.1158/1535-7163.mct-05-0273
    tissue_or_cell_type
    Ribonucleotide reductase small subunits

    Iron: absorption, trafficking, iron-dependent enzymes and nutrient interactions (2026-09-17) · lines 1187–1198

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Mutagenesis, EPR and catalytic assays · source_derived_draft · unverified_draft

    ### iron-rrm2b-iron-radical The corresponding conserved-tyrosine perturbation also disabled the radical and catalytic activity of the human p53R2/RRM2B system. Condition category: normal nutrient_topic: Iron research collection; topical membership is not evidence of a direct dietary effect. plain_language: The related small subunit is recorded separately so its role is not lost inside a generic enzyme label. organism: Human RRM2 and RRM2B proteins tissue_or_cell_type: Ribonucleotide reductase small subunits experimental_model: Mutagenesis, EPR and catalytic assays limitations: Purified enzyme mechanisms; no recommendation to increase dietary iron for DNA synthesis. exposure: Conserved tyrosine mutations around the diiron center evidence_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"} [iron-p16373698] A dityrosyl-diiron radical cofactor center is essential for human ribonucleotide reductases. (2005). https://pubmed.ncbi.nlm.nih.gov/16373698/ DOI: 10.1158/1535-7163.mct-05-0273
    Complete structured claim and evidence

In the sources

Preserved passages that mention this component, quoted exactly. Open one to read it in context.

    This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.

    Evidence, AI assistance and curation standards