Component

Pyridoxine 5-prime-phosphate

Phosphorylated pyridoxine, a PNPO substrate.

4 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. Catalytically active recombinant human pyridoxal phosphatase hydrolyzed pyridoxine-phosphate.

    Human pyridoxal phosphatase / PDXP → Pyridoxine 5-prime-phosphate source_derived_draftungraded
    Experimental context and source evidence
    evidence_location
    Indexed abstract: cloning and substrate hydrolysis
    experimental_model
    Recombinant human pyridoxal phosphatase expressed in E. coli.
    exposure
    Recombinant-enzyme characterization.
    limitations
    Model-specific evidence; no dietary threshold or treatment benefit established.
    nutrient_topic
    Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B6
    organism
    Homo sapiens
    plain_language
    PDXP removes phosphate from a B6 vitamer.
    primary_references
    [jang2003] Human pyridoxal phosphatase. Molecular cloning, functional expression, and tissue distribution. (2003). https://pubmed.ncbi.nlm.nih.gov/14522954/ DOI: 10.1074/jbc.m309619200
    tissue_or_cell_type
    Purified recombinant human enzyme

    Vitamin B6: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 269–280

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant human pyridoxal phosphatase expressed in E. coli. · source_derived_draft · unverified_draft

    ### b6-transport-pdxp-pnp Catalytically active recombinant human pyridoxal phosphatase hydrolyzed pyridoxine-phosphate. Condition category: normal nutrient_topic: Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. plain_language: PDXP removes phosphate from a B6 vitamer. organism: Homo sapiens tissue_or_cell_type: Purified recombinant human enzyme experimental_model: Recombinant human pyridoxal phosphatase expressed in E. coli. limitations: Model-specific evidence; no dietary threshold or treatment benefit established. exposure: Recombinant-enzyme characterization. evidence_location: Indexed abstract: cloning and substrate hydrolysis [jang2003] Human pyridoxal phosphatase. Molecular cloning, functional expression, and tissue distribution. (2003). https://pubmed.ncbi.nlm.nih.gov/14522954/ DOI: 10.1074/jbc.m309619200
    Complete structured claim and evidence

  2. Purified human PNPO converted PNP to PLP with a turnover number of 0.19 per second at 37 C.

    Pyridoxine 5-prime-phosphate oxidase / PNPO → Pyridoxine 5-prime-phosphate source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    B2-dependent oxidation activates one B6 precursor.
    evidence_location
    Results: kinetic properties; Table 1; FMN-binding structure
    experimental_model
    Recombinant human PNPO expressed in E. coli; crystallography and purified-enzyme kinetics at 37 C.
    exposure
    Purified-enzyme assay
    limitations
    Biochemical evidence does not establish a dietary threshold or supplementation benefit.
    nutrient_topic
    Riboflavin research collection; topical membership is not evidence of a direct dietary effect. · Riboflavin (vitamin B2)
    organism
    Homo sapiens
    plain_language
    PNPO changes phosphorylated pyridoxine into active B6.
    primary_references
    [musayev2003] Structure and properties of recombinant human pyridoxine 5'-phosphate oxidase. (2003). https://pubmed.ncbi.nlm.nih.gov/12824491/ DOI: 10.1110/ps.0356203
    tissue_or_cell_type
    Purified recombinant enzyme; no intact tissue

    Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1150–1162

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant human PNPO expressed in E. coli; crystallography and purified-enzyme kinetics at 37 C. · source_derived_draft · unverified_draft

    ### b2-pnpo-pnp-oxidation Purified human PNPO converted PNP to PLP with a turnover number of 0.19 per second at 37 C. Condition category: normal nutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect. plain_language: PNPO changes phosphorylated pyridoxine into active B6. organism: Homo sapiens tissue_or_cell_type: Purified recombinant enzyme; no intact tissue experimental_model: Recombinant human PNPO expressed in E. coli; crystallography and purified-enzyme kinetics at 37 C. limitations: Biochemical evidence does not establish a dietary threshold or supplementation benefit. exposure: Purified-enzyme assay cross_nutrient: B2-dependent oxidation activates one B6 precursor. evidence_location: Results: kinetic properties; Table 1; FMN-binding structure [musayev2003] Structure and properties of recombinant human pyridoxine 5'-phosphate oxidase. (2003). https://pubmed.ncbi.nlm.nih.gov/12824491/ DOI: 10.1110/ps.0356203
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Purified recombinant human PDXK phosphorylated pyridoxine to its corresponding 5-prime phosphate.

    Pyridoxal kinase / PDXK → Pyridoxine source_derived_draftungraded
    Experimental context and source evidence
    evidence_location
    Indexed abstract and publisher abstract; human enzyme findings only
    experimental_model
    Purified recombinant human and E. coli pyridoxal kinases.
    exposure
    Purified-enzyme substrate kinetics.
    limitations
    Model-specific evidence; no dietary threshold or treatment benefit established.
    nutrient_topic
    Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B6
    organism
    Homo sapiens
    plain_language
    PDXK adds phosphate to this B6 precursor.
    primary_references
    [disalvo2004] Expression, purification, and kinetic constants for human and Escherichia coli pyridoxal kinases. (2004). https://pubmed.ncbi.nlm.nih.gov/15249053/ DOI: 10.1016/j.pep.2004.04.021
    tissue_or_cell_type
    Purified human enzyme

    Vitamin B6: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 163–174

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified recombinant human and E. coli pyridoxal kinases. · source_derived_draft · unverified_draft

    ### b6-transport-pdxk-pn Purified recombinant human PDXK phosphorylated pyridoxine to its corresponding 5-prime phosphate. Condition category: normal nutrient_topic: Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. plain_language: PDXK adds phosphate to this B6 precursor. organism: Homo sapiens tissue_or_cell_type: Purified human enzyme experimental_model: Purified recombinant human and E. coli pyridoxal kinases. limitations: Model-specific evidence; no dietary threshold or treatment benefit established. exposure: Purified-enzyme substrate kinetics. evidence_location: Indexed abstract and publisher abstract; human enzyme findings only [disalvo2004] Expression, purification, and kinetic constants for human and Escherichia coli pyridoxal kinases. (2004). https://pubmed.ncbi.nlm.nih.gov/15249053/ DOI: 10.1016/j.pep.2004.04.021
    Complete structured claim and evidence

  2. R229W PNPO showed approximately 850-fold lower PNP catalytic efficiency, combining a 192-fold higher Km and 4.5-fold lower kcat.

    PNPO Arg229Trp protein → PLP source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    cross_nutrient
    B2-cofactor binding is one part of a broader genetic defect in B6 activation.
    evidence_location
    Results: Table 3 and Fig 1; Table 2 and Fig 2
    experimental_model
    Recombinant human wild-type and R229W PNPO; fluorescence titration, kinetics and 2.5-A mutant structure.
    exposure
    Purified-enzyme assay
    limitations
    Km is a kinetic parameter, not a direct binding constant; adding FMN alone was not shown to normalize this whole defect.
    nutrient_topic
    Riboflavin research collection; topical membership is not evidence of a direct dietary effect. · Riboflavin (vitamin B2)
    organism
    Homo sapiens
    plain_language
    The defect also changes substrate handling and reaction speed.
    primary_references
    [musayev2009] Molecular basis of reduced pyridoxine 5'-phosphate oxidase catalytic activity in neonatal epileptic encephalopathy disorder. (2009). https://pubmed.ncbi.nlm.nih.gov/19759001/ DOI: 10.1074/jbc.m109.038372
    tissue_or_cell_type
    Purified recombinant enzyme; no intact tissue
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1220–1232

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant human wild-type and R229W PNPO; fluorescence titration, kinetics and 2.5-A mutant structure. · source_derived_draft · unverified_draft

    ### b2-pnpo-r229w-catalytic-efficiency R229W PNPO showed approximately 850-fold lower PNP catalytic efficiency, combining a 192-fold higher Km and 4.5-fold lower kcat. Condition category: machinery_impairment nutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect. plain_language: The defect also changes substrate handling and reaction speed. organism: Homo sapiens tissue_or_cell_type: Purified recombinant enzyme; no intact tissue experimental_model: Recombinant human wild-type and R229W PNPO; fluorescence titration, kinetics and 2.5-A mutant structure. limitations: Km is a kinetic parameter, not a direct binding constant; adding FMN alone was not shown to normalize this whole defect. exposure: Purified-enzyme assay cross_nutrient: B2-cofactor binding is one part of a broader genetic defect in B6 activation. evidence_location: Results: Table 3 and Fig 1; Table 2 and Fig 2 [musayev2009] Molecular basis of reduced pyridoxine 5'-phosphate oxidase catalytic activity in neonatal epileptic encephalopathy disorder. (2009). https://pubmed.ncbi.nlm.nih.gov/19759001/ DOI: 10.1074/jbc.m109.038372
    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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