Component
Human homogentisate 1,2-dioxygenase / HGD
Context-specific entity; species, compartment and exposure are stated on each claim.
2 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
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.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
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.
What it acts on
Human HGD catalyzes aromatic-ring cleavage during phenylalanine/tyrosine degradation; its structure contains a coordinated active-site iron ion.
Experimental context and source evidence
- evidence_access
- Primary abstract
- experimental_model
- Human apo and iron-bound HGD crystallography.
- limitations
- The study is structural/enzymatic evidence, not a trial of iron supplementation.
- nutrient_topic
- L-Tyrosine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Tyrosine
- plain_language
- Iron-dependent chemistry opens the aromatic ring for further breakdown.
- primary_references
- Crystal structure of human homogentisate dioxygenase. · 2000 · https://pubmed.ncbi.nlm.nih.gov/10876237/ · DOI 10.1038/76756
L-Tyrosine: catecholamines, thyroid chemistry, pigment, metabolism and cross-nutrient mechanisms (2026-09-19) · lines 236–242
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human apo and iron-bound HGD crystallography. · source_derived_draft · unverified_draft
## l-tyrosine-hgd-ring Iron-dependent chemistry opens the aromatic ring for further breakdown. Human HGD catalyzes aromatic-ring cleavage during phenylalanine/tyrosine degradation; its structure contains a coordinated active-site iron ion. Model: Human apo and iron-bound HGD crystallography. Limitations: The study is structural/enzymatic evidence, not a trial of iron supplementation. Evidence access: Primary abstract Crystal structure of human homogentisate dioxygenase. · 2000 · https://pubmed.ncbi.nlm.nih.gov/10876237/ · DOI 10.1038/76756
Complete structured claim and evidenceAlkaptonuria-associated HGD missense variants were concentrated in intersubunit contact regions of the human enzyme structure.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- evidence_access
- Primary abstract
- experimental_model
- Mapping disease-associated variants onto a human hexameric structure.
- limitations
- Structural mapping is not a functional assay for every variant or a universal severity predictor.
- nutrient_topic
- L-Tyrosine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Tyrosine
- plain_language
- How enzyme subunits fit together can affect metabolic disposal.
- primary_references
- Crystal structure of human homogentisate dioxygenase. · 2000 · https://pubmed.ncbi.nlm.nih.gov/10876237/ · DOI 10.1038/76756
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
L-Tyrosine: catecholamines, thyroid chemistry, pigment, metabolism and cross-nutrient mechanisms (2026-09-19) · lines 244–250
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Mapping disease-associated variants onto a human hexameric structure. · source_derived_draft · unverified_draft
## l-tyrosine-hgd-variants How enzyme subunits fit together can affect metabolic disposal. Alkaptonuria-associated HGD missense variants were concentrated in intersubunit contact regions of the human enzyme structure. Model: Mapping disease-associated variants onto a human hexameric structure. Limitations: Structural mapping is not a functional assay for every variant or a universal severity predictor. Evidence access: Primary abstract Crystal structure of human homogentisate dioxygenase. · 2000 · https://pubmed.ncbi.nlm.nih.gov/10876237/ · DOI 10.1038/76756
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.