Component

Escherichia coli K12 azoreductase II preparation

Purified 1993 activity: 12-kDa monomer. Gene identity unresolved; retained separately from azoreductase I.

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 it acts on

  1. Purified E. coli K12 azoreductase II used tartrazine less efficiently than azoreductase I.

    Escherichia coli K12 azoreductase II preparation → Tartrazine source_derived_draftungraded
    Experimental context and source evidence
    dose
    Tartrazine among tested substrates; exact substrate/cofactor concentrations unavailable in abstract
    duration
    Assay interval unavailable in primary abstract
    evidence_access
    Primary PubMed abstract; unrecovered method details explicitly retained.
    evidence_scope
    literature_reviewed; source-specific experimental curation
    experimental_model
    Purified Escherichia coli K12 azoreductases I and II
    limitations
    Both NADH and NADPH served as electron donors in enzyme characterization. This does not prove that niacin intake controls dye metabolism in humans. Protein genes and tartrazine-specific kinetic constants are unresolved.
    nutrient_topic
    Tartrazine food-colorant chapter; nutrient, drug and peptide interactions retain their models and limits. · Tartrazine
    organism
    Purified Escherichia coli K12 azoreductases I and II
    plain_language
    Purified E. coli K12 azoreductase II used tartrazine less efficiently than azoreductase I.
    primary_references
    Purification of two azoreductases from Escherichia coli K12. (1993). https://pubmed.ncbi.nlm.nih.gov/8112774/
    route
    In vitro enzyme/substrate incubation
    tissue
    Cell-free azo-reduction assays

    Tartrazine: mechanisms, molecular forms and cross-actor connections (2026-09-20) · lines 28–37

    Original AI-assisted curation of eighteen primary studies. Study-specific citations, negative findings and limitations retained. Not publisher full text. · supports · Purified Escherichia coli K12 azoreductases I and II · source_derived_draft · unverified_draft

    ## tartrazine-azoreductase-ii Purified E. coli K12 azoreductase II used tartrazine less efficiently than azoreductase I. Model/species: Purified Escherichia coli K12 azoreductases I and II Tissue: Cell-free azo-reduction assays Exposure: Tartrazine among tested substrates; exact substrate/cofactor concentrations unavailable in abstract Route: In vitro enzyme/substrate incubation Duration: Assay interval unavailable in primary abstract Limits: Both NADH and NADPH served as electron donors in enzyme characterization. This does not prove that niacin intake controls dye metabolism in humans. Protein genes and tartrazine-specific kinetic constants are unresolved. Primary reference: Purification of two azoreductases from Escherichia coli K12. (1993). https://pubmed.ncbi.nlm.nih.gov/8112774/ Access: Primary PubMed abstract; unrecovered method details explicitly retained.
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. NADH functioned as an electron donor for the purified azoreductases characterized with an azo-dye substrate panel including tartrazine.

    NADH → Escherichia coli K12 azoreductase I preparation source_derived_draftungraded
    Experimental context and source evidence
    dose
    Tartrazine among tested substrates; exact substrate/cofactor concentrations unavailable in abstract
    duration
    Assay interval unavailable in primary abstract
    evidence_access
    Primary PubMed abstract; unrecovered method details explicitly retained.
    evidence_scope
    literature_reviewed; source-specific experimental curation
    experimental_model
    Purified Escherichia coli K12 azoreductases I and II
    limitations
    Both NADH and NADPH served as electron donors in enzyme characterization. This does not prove that niacin intake controls dye metabolism in humans. Protein genes and tartrazine-specific kinetic constants are unresolved.
    nutrient_topic
    Tartrazine food-colorant chapter; nutrient, drug and peptide interactions retain their models and limits. · Tartrazine
    organism
    Purified Escherichia coli K12 azoreductases I and II
    plain_language
    NADH functioned as an electron donor for the purified azoreductases characterized with an azo-dye substrate panel including tartrazine.
    primary_references
    Purification of two azoreductases from Escherichia coli K12. (1993). https://pubmed.ncbi.nlm.nih.gov/8112774/
    route
    In vitro enzyme/substrate incubation
    tissue
    Cell-free azo-reduction assays

    Tartrazine: mechanisms, molecular forms and cross-actor connections (2026-09-20) · lines 39–48

    Original AI-assisted curation of eighteen primary studies. Study-specific citations, negative findings and limitations retained. Not publisher full text. · supports · Purified Escherichia coli K12 azoreductases I and II · source_derived_draft · unverified_draft

    ## tartrazine-nadh-donor NADH functioned as an electron donor for the purified azoreductases characterized with an azo-dye substrate panel including tartrazine. Model/species: Purified Escherichia coli K12 azoreductases I and II Tissue: Cell-free azo-reduction assays Exposure: Tartrazine among tested substrates; exact substrate/cofactor concentrations unavailable in abstract Route: In vitro enzyme/substrate incubation Duration: Assay interval unavailable in primary abstract Limits: Both NADH and NADPH served as electron donors in enzyme characterization. This does not prove that niacin intake controls dye metabolism in humans. Protein genes and tartrazine-specific kinetic constants are unresolved. Primary reference: Purification of two azoreductases from Escherichia coli K12. (1993). https://pubmed.ncbi.nlm.nih.gov/8112774/ Access: Primary PubMed abstract; unrecovered method details explicitly retained.
    Complete structured claim and evidence

  2. NADPH also functioned as an electron donor for the purified E. coli azoreductase preparations.

    NADPH → Escherichia coli K12 azoreductase I preparation source_derived_draftungraded
    Experimental context and source evidence
    dose
    Tartrazine among tested substrates; exact substrate/cofactor concentrations unavailable in abstract
    duration
    Assay interval unavailable in primary abstract
    evidence_access
    Primary PubMed abstract; unrecovered method details explicitly retained.
    evidence_scope
    literature_reviewed; source-specific experimental curation
    experimental_model
    Purified Escherichia coli K12 azoreductases I and II
    limitations
    Both NADH and NADPH served as electron donors in enzyme characterization. This does not prove that niacin intake controls dye metabolism in humans. Protein genes and tartrazine-specific kinetic constants are unresolved.
    nutrient_topic
    Tartrazine food-colorant chapter; nutrient, drug and peptide interactions retain their models and limits. · Tartrazine
    organism
    Purified Escherichia coli K12 azoreductases I and II
    plain_language
    NADPH also functioned as an electron donor for the purified E. coli azoreductase preparations.
    primary_references
    Purification of two azoreductases from Escherichia coli K12. (1993). https://pubmed.ncbi.nlm.nih.gov/8112774/
    route
    In vitro enzyme/substrate incubation
    tissue
    Cell-free azo-reduction assays

    Tartrazine: mechanisms, molecular forms and cross-actor connections (2026-09-20) · lines 50–59

    Original AI-assisted curation of eighteen primary studies. Study-specific citations, negative findings and limitations retained. Not publisher full text. · supports · Purified Escherichia coli K12 azoreductases I and II · source_derived_draft · unverified_draft

    ## tartrazine-nadph-donor NADPH also functioned as an electron donor for the purified E. coli azoreductase preparations. Model/species: Purified Escherichia coli K12 azoreductases I and II Tissue: Cell-free azo-reduction assays Exposure: Tartrazine among tested substrates; exact substrate/cofactor concentrations unavailable in abstract Route: In vitro enzyme/substrate incubation Duration: Assay interval unavailable in primary abstract Limits: Both NADH and NADPH served as electron donors in enzyme characterization. This does not prove that niacin intake controls dye metabolism in humans. Protein genes and tartrazine-specific kinetic constants are unresolved. Primary reference: Purification of two azoreductases from Escherichia coli K12. (1993). https://pubmed.ncbi.nlm.nih.gov/8112774/ Access: Primary PubMed abstract; unrecovered method details explicitly retained.
    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