Component

(S)-Methylmalonyl-CoA

(S)-Methylmalonyl-CoA

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. Human MCEE interconverts methylmalonyl-CoA epimers, supplying the (R) form for MMUT; MCEE expression increased coupled succinate production.

    Human methylmalonyl-CoA epimerase / MCEE → (S)-Methylmalonyl-CoA source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    false
    evidence_location
    Full text Methods 2.6 and Results 3.6; Figure 5
    experimental_model
    Human fibroblast lysates overexpressing MCEE and/or MMUT
    exposure
    Radiolabeled propionyl-CoA; MCEE/MMUT expression and AdoCbl
    limitations
    Coupled labeled hydrolysis-product assay; MCEE being limiting here is not a universal in-vivo rate limitation.
    nutrient_topic
    Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
    organism
    Homo sapiens
    plain_language
    Human fibroblast assays showed why the epimerase step matters before the B12 enzyme.
    primary_references
    [heuberger-2019-mcee] Genetic, structural, and functional analysis of pathogenic variations causing methylmalonyl-CoA epimerase deficiency. (2019). https://pubmed.ncbi.nlm.nih.gov/30682498/ DOI: 10.1016/j.bbadis.2019.01.021
    tissue_or_cell_type
    Fibroblasts

    Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1174–1186

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human fibroblast lysates overexpressing MCEE and/or MMUT · source_derived_draft · unverified_draft

    ### mcee-epimerizes-methylmalonyl-coa Human MCEE interconverts methylmalonyl-CoA epimers, supplying the (R) form for MMUT; MCEE expression increased coupled succinate production. Condition category: normal nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: Human fibroblast assays showed why the epimerase step matters before the B12 enzyme. organism: Homo sapiens tissue_or_cell_type: Fibroblasts experimental_model: Human fibroblast lysates overexpressing MCEE and/or MMUT limitations: Coupled labeled hydrolysis-product assay; MCEE being limiting here is not a universal in-vivo rate limitation. exposure: Radiolabeled propionyl-CoA; MCEE/MMUT expression and AdoCbl cross_nutrient: false evidence_location: Full text Methods 2.6 and Results 3.6; Figure 5 [heuberger-2019-mcee] Genetic, structural, and functional analysis of pathogenic variations causing methylmalonyl-CoA epimerase deficiency. (2019). https://pubmed.ncbi.nlm.nih.gov/30682498/ DOI: 10.1016/j.bbadis.2019.01.021
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. PCCB provides the carboxyltransferase activity of human PCC.

    Human propionyl-CoA carboxylase beta subunit / PCCB → Human propionyl-CoA carboxylase / PCC source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/biotin-research/20725044.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "825bf28b9f35a8d45f8d08d883fa200bd430336b0558db035ce4fd1c5ef19053", "start_char": 0, "end_char": 1921, "text_sha256": "825bf28b9f35a8d45f8d08d883fa200bd430336b0558db035ce4fd1c5ef19053"}
    experimental_model
    Bacterial PCC crystallography and separate 15-angstrom human PCC cryo-EM reconstruction
    exposure
    Structural analysis
    limitations
    Atomic bacterial positions are not high-resolution human measurements. Human cryo-EM establishes the overall assembly at lower resolution.
    nutrient_topic
    Biotin research collection; topical membership is not evidence of a direct dietary effect. · Biotin
    organism
    Homo sapiens; bacterial PCC comparison
    plain_language
    The beta subunit performs the transfer onto the carbon substrate.
    primary_references
    [b7-p20725044] Crystal structure of the alpha(6)beta(6) holoenzyme of propionyl-coenzyme A carboxylase. (2010). https://pubmed.ncbi.nlm.nih.gov/20725044/ DOI: 10.1038/nature09302
    tissue_or_cell_type
    Purified PCC complexes

    Biotin: carboxylases, recycling, deficiency and nutrient interactions (2026-09-17) · lines 611–622

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Bacterial PCC crystallography and separate 15-angstrom human PCC cryo-EM reconstruction · source_derived_draft · unverified_draft

    ### b7-pcc-pccb PCCB provides the carboxyltransferase activity of human PCC. Condition category: normal nutrient_topic: Biotin research collection; topical membership is not evidence of a direct dietary effect. plain_language: The beta subunit performs the transfer onto the carbon substrate. organism: Homo sapiens; bacterial PCC comparison tissue_or_cell_type: Purified PCC complexes experimental_model: Bacterial PCC crystallography and separate 15-angstrom human PCC cryo-EM reconstruction limitations: Atomic bacterial positions are not high-resolution human measurements. Human cryo-EM establishes the overall assembly at lower resolution. exposure: Structural analysis evidence_span: {"source_cache": "artifacts/biotin-research/20725044.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "825bf28b9f35a8d45f8d08d883fa200bd430336b0558db035ce4fd1c5ef19053", "start_char": 0, "end_char": 1921, "text_sha256": "825bf28b9f35a8d45f8d08d883fa200bd430336b0558db035ce4fd1c5ef19053"} [b7-p20725044] Crystal structure of the alpha(6)beta(6) holoenzyme of propionyl-coenzyme A carboxylase. (2010). https://pubmed.ncbi.nlm.nih.gov/20725044/ DOI: 10.1038/nature09302
    Complete structured claim and evidence

  2. Human PCC supplies (S)-methylmalonyl-CoA by propionyl-CoA carboxylation upstream of the MCEE-MMUT sequence examined in fibroblast assays.

    Human propionyl-CoA carboxylase / PCC → Propionyl-CoA source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    true
    evidence_location
    Indexed primary abstract; Full text Methods 2.6 and Results 3.6; Figure 5
    experimental_model
    Human fibroblast PCC and coupled-pathway assays
    exposure
    Propionyl-CoA, ATP and bicarbonate in enzyme pathway
    limitations
    Pathway assignment combines human PCC characterization with coupled assays; it is not a simultaneous dietary biotin/B12 intervention.
    nutrient_topic
    Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
    organism
    Homo sapiens
    plain_language
    Biotin-dependent PCC makes the precursor that must be rearranged before human MMUT can use B12 on it.
    primary_references
    [hsia-1979-pcc] Human propionyl CoA carboxylase: some properties of the partially purified enzyme in fibroblasts from controls and patients with propionic acidemia. (1979). https://pubmed.ncbi.nlm.nih.gov/481943/ DOI: 10.1203/00006450-197906000-00005 [heuberger-2019-mcee] Genetic, structural, and functional analysis of pathogenic variations causing methylmalonyl-CoA epimerase deficiency. (2019). https://pubmed.ncbi.nlm.nih.gov/30682498/ DOI: 10.1016/j.bbadis.2019.01.021
    tissue_or_cell_type
    Fibroblasts

    Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1159–1172

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human fibroblast PCC and coupled-pathway assays · source_derived_draft · unverified_draft

    ### pcc-carboxylation-upstream-b12 Human PCC supplies (S)-methylmalonyl-CoA by propionyl-CoA carboxylation upstream of the MCEE-MMUT sequence examined in fibroblast assays. Condition category: normal nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: Biotin-dependent PCC makes the precursor that must be rearranged before human MMUT can use B12 on it. organism: Homo sapiens tissue_or_cell_type: Fibroblasts experimental_model: Human fibroblast PCC and coupled-pathway assays limitations: Pathway assignment combines human PCC characterization with coupled assays; it is not a simultaneous dietary biotin/B12 intervention. exposure: Propionyl-CoA, ATP and bicarbonate in enzyme pathway cross_nutrient: true evidence_location: Indexed primary abstract; Full text Methods 2.6 and Results 3.6; Figure 5 [hsia-1979-pcc] Human propionyl CoA carboxylase: some properties of the partially purified enzyme in fibroblasts from controls and patients with propionic acidemia. (1979). https://pubmed.ncbi.nlm.nih.gov/481943/ DOI: 10.1203/00006450-197906000-00005 [heuberger-2019-mcee] Genetic, structural, and functional analysis of pathogenic variations causing methylmalonyl-CoA epimerase deficiency. (2019). https://pubmed.ncbi.nlm.nih.gov/30682498/ DOI: 10.1016/j.bbadis.2019.01.021
    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