Component

SHMT1

Independent protein record; interpretation is limited by each linked claim and its study context.

5 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. Human SHMT1 uses PLP to couple serine-to-glycine conversion with transfer of a one-carbon unit to tetrahydrofolate.

    SHMT1 → 5,10-Methylenetetrahydrofolate source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    PLP (B6) and THF (folate) cooperate in one reaction.
    experimental_model
    Purified human SHMT1 and SHMT2; structures and solution oligomerization
    limitations
    Reaction is reversible; assembly assays do not establish flux in every cell.
    nutrient_topic
    Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B6
    organism
    Homo sapiens
    plain_language
    The enzyme connects B6-dependent amino-acid chemistry to folate chemistry.
    primary_references
    [b6-shmt-2015] How pyridoxal 5'-phosphate differentially regulates human cytosolic and mitochondrial serine hydroxymethyltransferase oligomeric state (2015). https://febs.onlinelibrary.wiley.com/doi/10.1111/febs.13211 DOI: 10.1111/febs.13211
    tissue_or_cell_type
    Purified recombinant protein; no intact tissue

    Vitamin B6: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 602–612

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified human SHMT1 and SHMT2; structures and solution oligomerization · source_derived_draft · unverified_draft

    ### b6-met-shmt1-onecarbon Human SHMT1 uses PLP to couple serine-to-glycine conversion with transfer of a one-carbon unit to tetrahydrofolate. Condition category: normal nutrient_topic: Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. plain_language: The enzyme connects B6-dependent amino-acid chemistry to folate chemistry. organism: Homo sapiens tissue_or_cell_type: Purified recombinant protein; no intact tissue experimental_model: Purified human SHMT1 and SHMT2; structures and solution oligomerization limitations: Reaction is reversible; assembly assays do not establish flux in every cell. cross_nutrient: PLP (B6) and THF (folate) cooperate in one reaction. [b6-shmt-2015] How pyridoxal 5'-phosphate differentially regulates human cytosolic and mitochondrial serine hydroxymethyltransferase oligomeric state (2015). https://febs.onlinelibrary.wiley.com/doi/10.1111/febs.13211 DOI: 10.1111/febs.13211
    Complete structured claim and evidence

  2. In nutrient-replete HEK293T and HCT116 cells, isotope tracing showed net SHMT1 flux toward serine synthesis.

    SHMT1 → L-Serine source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    Links existing B6-dependent SHMT chemistry to folate flux direction.
    experimental_model
    Stable-isotope tracing
    exposure
    Assay conditions described in the linked primary study.
    limitations
    Not a universal direction across tissues or nutrition states.
    nutrient_topic
    Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect. · Folate (vitamin B9)
    organism
    Homo sapiens
    plain_language
    SHMT1 can consume one-carbon units instead of producing them.
    primary_references
    [ducker-2016] Reversal of Cytosolic One-Carbon Flux Compensates for Loss of the Mitochondrial Folate Pathway (2016). https://pubmed.ncbi.nlm.nih.gov/27211901/ DOI: 10.1016/j.cmet.2016.04.016
    tissue_or_cell_type
    HEK293T and HCT116 cells

    Folate and folic acid: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 923–934

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Stable-isotope tracing · source_derived_draft · unverified_draft

    ### shmt1-reverse-flux-replete In nutrient-replete HEK293T and HCT116 cells, isotope tracing showed net SHMT1 flux toward serine synthesis. Condition category: normal nutrient_topic: Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: SHMT1 can consume one-carbon units instead of producing them. organism: Homo sapiens tissue_or_cell_type: HEK293T and HCT116 cells experimental_model: Stable-isotope tracing limitations: Not a universal direction across tissues or nutrition states. exposure: Assay conditions described in the linked primary study. cross_nutrient: Links existing B6-dependent SHMT chemistry to folate flux direction. [ducker-2016] Reversal of Cytosolic One-Carbon Flux Compensates for Loss of the Mitochondrial Folate Pathway (2016). https://pubmed.ncbi.nlm.nih.gov/27211901/ DOI: 10.1016/j.cmet.2016.04.016
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Human SHMT1 remained tetrameric with and without PLP in the tested solution conditions.

    PLP → SHMT1 tetramer assembly source_derived_draftungraded
    Experimental context and source evidence
    experimental_model
    Purified human SHMT1 and SHMT2; structures and solution oligomerization
    limitations
    Tetramer persistence does not mean cofactor-free SHMT1 can perform normal catalysis.
    nutrient_topic
    Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B6
    organism
    Homo sapiens
    plain_language
    SHMT1 assembly responds differently from SHMT2.
    primary_references
    [b6-shmt-2015] How pyridoxal 5'-phosphate differentially regulates human cytosolic and mitochondrial serine hydroxymethyltransferase oligomeric state (2015). https://febs.onlinelibrary.wiley.com/doi/10.1111/febs.13211 DOI: 10.1111/febs.13211
    tissue_or_cell_type
    Purified recombinant protein; no intact tissue

    Vitamin B6: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 637–646

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified human SHMT1 and SHMT2; structures and solution oligomerization · source_derived_draft · unverified_draft

    ### b6-met-shmt1-assembly Human SHMT1 remained tetrameric with and without PLP in the tested solution conditions. Condition category: normal nutrient_topic: Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. plain_language: SHMT1 assembly responds differently from SHMT2. organism: Homo sapiens tissue_or_cell_type: Purified recombinant protein; no intact tissue experimental_model: Purified human SHMT1 and SHMT2; structures and solution oligomerization limitations: Tetramer persistence does not mean cofactor-free SHMT1 can perform normal catalysis. [b6-shmt-2015] How pyridoxal 5'-phosphate differentially regulates human cytosolic and mitochondrial serine hydroxymethyltransferase oligomeric state (2015). https://febs.onlinelibrary.wiley.com/doi/10.1111/febs.13211 DOI: 10.1111/febs.13211
    Complete structured claim and evidence

  2. Purified human SHMT1 cleaves hydroxytrimethyllysine into trimethylaminobutyraldehyde and glycine.

    (2S,3S)-3-Hydroxy-N-epsilon-trimethyllysine → 4-Trimethylaminobutyraldehyde source_derived_draftungraded
    Experimental context and source evidence
    experimental_model
    Purified human enzyme; NMR and coupled activity assays
    limitations
    Whole-body flux contribution remains unquantified.
    organism
    Homo sapiens
    plain_language
    SHMT1 can perform the second carnitine-synthesis reaction.
    primary_references
    [osmes2024] One substrate many enzymes virtual screening uncovers missing genes of carnitine biosynthesis in human and mouse (2024). https://www.nature.com/articles/s41467-024-47466-3 DOI: 10.1038/s41467-024-47466-3
    tissue_or_cell_type
    Cytosolic enzyme tested in vitro

    L-Lysine: mechanism-first literature curation (2026-09-17) · lines 177–185

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified human enzyme; NMR and coupled activity assays · source_derived_draft · unverified_draft

    ### shmt1-html-cleavage Purified human SHMT1 cleaves hydroxytrimethyllysine into trimethylaminobutyraldehyde and glycine. Plain language: SHMT1 can perform the second carnitine-synthesis reaction. Condition category: normal organism: Homo sapiens tissue_or_cell_type: Cytosolic enzyme tested in vitro experimental_model: Purified human enzyme; NMR and coupled activity assays limitations: Whole-body flux contribution remains unquantified. [osmes2024] One substrate many enzymes virtual screening uncovers missing genes of carnitine biosynthesis in human and mouse (2024). https://www.nature.com/articles/s41467-024-47466-3 DOI: 10.1038/s41467-024-47466-3
    Complete structured claim and evidence

  3. MTHFD2 deletion depleted formyl-folate availability and activated cytosolic serine-derived one-carbon production.

    Human MTHFD2 gene → Human MTHFD1 source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    experimental_model
    CRISPR and isotope tracing
    exposure
    Assay conditions described in the linked primary study.
    limitations
    Compensation depends on nutrient availability.
    nutrient_topic
    Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect. · Folate (vitamin B9)
    organism
    Homo sapiens
    plain_language
    Cells can reroute carbon production after losing the mitochondrial pathway.
    primary_references
    [ducker-2016] Reversal of Cytosolic One-Carbon Flux Compensates for Loss of the Mitochondrial Folate Pathway (2016). https://pubmed.ncbi.nlm.nih.gov/27211901/ DOI: 10.1016/j.cmet.2016.04.016
    tissue_or_cell_type
    HEK293T cells
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Folate and folic acid: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 899–909

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · CRISPR and isotope tracing · source_derived_draft · unverified_draft

    ### mitochondrial-loss-cytosolic-reversal MTHFD2 deletion depleted formyl-folate availability and activated cytosolic serine-derived one-carbon production. Condition category: machinery_impairment nutrient_topic: Folate and folic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: Cells can reroute carbon production after losing the mitochondrial pathway. organism: Homo sapiens tissue_or_cell_type: HEK293T cells experimental_model: CRISPR and isotope tracing limitations: Compensation depends on nutrient availability. exposure: Assay conditions described in the linked primary study. [ducker-2016] Reversal of Cytosolic One-Carbon Flux Compensates for Loss of the Mitochondrial Folate Pathway (2016). https://pubmed.ncbi.nlm.nih.gov/27211901/ DOI: 10.1016/j.cmet.2016.04.016
    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