Component

5-Hydroxy-L-tryptophan

5-Hydroxy-L-tryptophan

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. Purified human pineal TPH catalyzed tryptophan hydroxylation to 5-hydroxytryptophan.

    Human tryptophan hydroxylase 1 / TPH1 → 5-Hydroxy-L-tryptophan source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/melatonin-research/10525150.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "032acfb7b1818f5282f5457e093a7e371895bbdc95f058c8958766fc57f9118f", "start_char": 0, "end_char": 1489, "text_sha256": "032acfb7b1818f5282f5457e093a7e371895bbdc95f058c8958766fc57f9118f"}
    experimental_model
    Recombinant enzyme purification and catalysis
    exposure
    L-tryptophan with tetrahydrobiopterin; purified tetrameric enzyme
    limitations
    TPH1 and neuronal TPH2 are distinct. A cofactor-dependent reaction does not prove supplemental cofactor increases melatonin in a replete person.
    nutrient_topic
    Melatonin research collection; topical membership is not evidence of a direct dietary effect. · Melatonin
    organism
    Human pineal TPH1 expressed in E. coli
    plain_language
    The amino acid tryptophan must pass through an enzyme-controlled first step.
    primary_references
    [melatonin-p10525150] Cloning and expression of recombinant human pineal tryptophan hydroxylase in Escherichia coli: purification and characterization of the cloned enzyme. (1999). https://pubmed.ncbi.nlm.nih.gov/10525150/ DOI: 10.1016/s0167-4838(99)00184-3
    tissue_or_cell_type
    Tryptophan hydroxylation

    Melatonin: synthesis, receptors, circadian timing and nutrient interactions (2026-09-17) · lines 136–147

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant enzyme purification and catalysis · source_derived_draft · unverified_draft

    ### melatonin-tph1-hydroxylation Purified human pineal TPH catalyzed tryptophan hydroxylation to 5-hydroxytryptophan. Condition category: normal nutrient_topic: Melatonin research collection; topical membership is not evidence of a direct dietary effect. plain_language: The amino acid tryptophan must pass through an enzyme-controlled first step. organism: Human pineal TPH1 expressed in E. coli tissue_or_cell_type: Tryptophan hydroxylation experimental_model: Recombinant enzyme purification and catalysis limitations: TPH1 and neuronal TPH2 are distinct. A cofactor-dependent reaction does not prove supplemental cofactor increases melatonin in a replete person. exposure: L-tryptophan with tetrahydrobiopterin; purified tetrameric enzyme evidence_span: {"source_cache": "artifacts/melatonin-research/10525150.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "032acfb7b1818f5282f5457e093a7e371895bbdc95f058c8958766fc57f9118f", "start_char": 0, "end_char": 1489, "text_sha256": "032acfb7b1818f5282f5457e093a7e371895bbdc95f058c8958766fc57f9118f"} [melatonin-p10525150] Cloning and expression of recombinant human pineal tryptophan hydroxylase in Escherichia coli: purification and characterization of the cloned enzyme. (1999). https://pubmed.ncbi.nlm.nih.gov/10525150/ DOI: 10.1016/s0167-4838(99)00184-3
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Expressed human DDC decarboxylated 5-hydroxy-L-tryptophan; added PLP enhanced the measured activity.

    Human aromatic L-amino acid decarboxylase / DDC → Serotonin source_derived_draftungraded
    Experimental context and source evidence
    experimental_model
    Human DDC expressed in monkey COS cells; enzyme assays
    exposure
    PLP addition to transfected COS-cell enzyme incubations.
    limitations
    An expression-system response is not proof that supplements increase brain monoamines.
    nutrient_topic
    Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B6
    organism
    Human DDC expressed in monkey COS cells
    plain_language
    B6 cofactor supports this monoamine-producing step.
    primary_references
    [sumi-1990-ddc] Characterization of recombinant human aromatic L-amino acid decarboxylase expressed in COS cells (1990). https://doi.org/10.1111/j.1471-4159.1990.tb04601.x DOI: 10.1111/j.1471-4159.1990.tb04601.x
    tissue_or_cell_type
    COS-cell expression system

    Vitamin B6: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1011–1021

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human DDC expressed in monkey COS cells; enzyme assays · source_derived_draft · unverified_draft

    ### b6-neuro-ddc-serotonin Expressed human DDC decarboxylated 5-hydroxy-L-tryptophan; added PLP enhanced the measured activity. Condition category: normal nutrient_topic: Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. plain_language: B6 cofactor supports this monoamine-producing step. organism: Human DDC expressed in monkey COS cells tissue_or_cell_type: COS-cell expression system experimental_model: Human DDC expressed in monkey COS cells; enzyme assays limitations: An expression-system response is not proof that supplements increase brain monoamines. exposure: PLP addition to transfected COS-cell enzyme incubations. [sumi-1990-ddc] Characterization of recombinant human aromatic L-amino acid decarboxylase expressed in COS cells (1990). https://doi.org/10.1111/j.1471-4159.1990.tb04601.x DOI: 10.1111/j.1471-4159.1990.tb04601.x
    Complete structured claim and evidence

  2. TnaA also converted 5-HTP to 5-hydroxyindole, with lower catalytic efficiency than for tryptophan.

    Escherichia coli BW25113 tryptophanase / TnaA → 5-Hydroxyindole source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary full text, Figure 2
    experimental_model
    Purified E. coli enzyme and tnaA-mutant experiments.
    limitations
    5-HTP and tryptophan are distinct substrates, not interchangeable supplement exposures.
    nutrient_topic
    Tryptophan collection; molecular form, preparation, species, exposure and manipulation remain explicit. · L-Tryptophan
    plain_language
    The serotonin precursor can instead become a microbial product.
    primary_references
    Gut bacteria-derived 5-hydroxyindole is a potent stimulant of intestinal motility via its action on L-type calcium channels. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33481771/ · DOI 10.1371/journal.pbio.3001070

    Tryptophan: transport, protein synthesis, neuroactive metabolites, NAD and microbial pathways (2026-09-19) · lines 642–648

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Purified E. coli enzyme and tnaA-mutant experiments. · source_derived_draft · unverified_draft

    ## tryptophan-tnaa-hydroxyindole The serotonin precursor can instead become a microbial product. TnaA also converted 5-HTP to 5-hydroxyindole, with lower catalytic efficiency than for tryptophan. Model: Purified E. coli enzyme and tnaA-mutant experiments. Limitations: 5-HTP and tryptophan are distinct substrates, not interchangeable supplement exposures. Evidence access: Primary full text, Figure 2 Gut bacteria-derived 5-hydroxyindole is a potent stimulant of intestinal motility via its action on L-type calcium channels. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33481771/ · DOI 10.1371/journal.pbio.3001070
    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.

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