Component

Hydrogen ion

H+; proton activity and concentration depend on compartment and buffering.

11 recorded relationships. Experimental role, claim status and evidence remain attached to each record.

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. In the egg-yolk/human saliva model, acidification to pH 1.5 permitted limited cobalamin transfer to R binder; virtually none occurred above pH 2 despite pepsin.

    Experimental context and source evidence
    cross_nutrient
    false
    experimental_model
    In vitro egg-yolk cobalamin-binding protein mixed with human saliva/gastric juice
    exposure
    In vitro pH manipulation
    limitations
    Food-specific biochemical model; this pH threshold is not a clinical blood threshold or proof that all foods behave identically. Pepsin preparation species was not specified in the inspected abstract.
    nutrient_topic
    Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
    organism
    Homo sapiens
    plain_language
    Acid enabled release and capture of B12 from this food model.
    primary_references
    [carmel-1990-food-transfer] Transfer of cobalamin from the cobalamin-binding protein of egg yolk to R binder of human saliva and gastric juice. (1990). https://pubmed.ncbi.nlm.nih.gov/2110915/ DOI: 10.1016/0016-5085(90)91076-i
    tissue_or_cell_type
    Gastric luminal digestion model

    Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 88–99

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · In vitro egg-yolk cobalamin-binding protein mixed with human saliva/gastric juice · source_derived_draft · unverified_draft

    ### b12-abs-food-acid In the egg-yolk/human saliva model, acidification to pH 1.5 permitted limited cobalamin transfer to R binder; virtually none occurred above pH 2 despite pepsin. Condition category: normal nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: Acid enabled release and capture of B12 from this food model. organism: Homo sapiens tissue_or_cell_type: Gastric luminal digestion model experimental_model: In vitro egg-yolk cobalamin-binding protein mixed with human saliva/gastric juice limitations: Food-specific biochemical model; this pH threshold is not a clinical blood threshold or proof that all foods behave identically. Pepsin preparation species was not specified in the inspected abstract. exposure: In vitro pH manipulation cross_nutrient: false [carmel-1990-food-transfer] Transfer of cobalamin from the cobalamin-binding protein of egg yolk to R binder of human saliva and gastric juice. (1990). https://pubmed.ncbi.nlm.nih.gov/2110915/ DOI: 10.1016/0016-5085(90)91076-i
    Complete structured claim and evidence
  2. Lowering assay pH from 7.5 to 6.5 increased the reported mARC NO-formation rate by nearly threefold.

    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/molybdenum-research/24500710.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "e4c2ab41c945d420266290d0241752039d7de2cb6223f9c64c7d0525c5688d9b", "start_char": 0, "end_char": 1585, "text_sha256": "e4c2ab41c945d420266290d0241752039d7de2cb6223f9c64c7d0525c5688d9b"}
    experimental_model
    Recombinant human mARC1/mARC2, active-site mutation, tungsten replacement and HEK expression
    exposure
    Reduced enzyme, nitrite, NADH/CYB5/CYB5R; pH 7.5 versus 6.5
    limitations
    Shows nitrite-reducing capacity; its share of NO production in normal people and response to mineral intake are not established.
    nutrient_topic
    Molybdenum research collection; topical membership is not evidence of a direct dietary effect. · Molybdenum
    organism
    Homo sapiens proteins and HEK cells
    plain_language
    Acidity changed the reaction rate in this assay.
    primary_references
    [mo-p24500710] Nitrite reductase and nitric-oxide synthase activity of the mitochondrial molybdopterin enzymes mARC1 and mARC2. (2014). https://pubmed.ncbi.nlm.nih.gov/24500710/ DOI: 10.1074/jbc.m114.555177
    tissue_or_cell_type
    Purified redox system and human cell model

    Molybdenum: cofactor assembly, sulfur metabolism and nutrient interactions (2026-09-17) · lines 1054–1065

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant human mARC1/mARC2, active-site mutation, tungsten replacement and HEK expression · source_derived_draft · unverified_draft

    ### mo-marc-ph Lowering assay pH from 7.5 to 6.5 increased the reported mARC NO-formation rate by nearly threefold. Condition category: normal nutrient_topic: Molybdenum research collection; topical membership is not evidence of a direct dietary effect. plain_language: Acidity changed the reaction rate in this assay. organism: Homo sapiens proteins and HEK cells tissue_or_cell_type: Purified redox system and human cell model experimental_model: Recombinant human mARC1/mARC2, active-site mutation, tungsten replacement and HEK expression limitations: Shows nitrite-reducing capacity; its share of NO production in normal people and response to mineral intake are not established. exposure: Reduced enzyme, nitrite, NADH/CYB5/CYB5R; pH 7.5 versus 6.5 evidence_span: {"source_cache": "artifacts/molybdenum-research/24500710.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "e4c2ab41c945d420266290d0241752039d7de2cb6223f9c64c7d0525c5688d9b", "start_char": 0, "end_char": 1585, "text_sha256": "e4c2ab41c945d420266290d0241752039d7de2cb6223f9c64c7d0525c5688d9b"} [mo-p24500710] Nitrite reductase and nitric-oxide synthase activity of the mitochondrial molybdopterin enzymes mARC1 and mARC2. (2014). https://pubmed.ncbi.nlm.nih.gov/24500710/ DOI: 10.1074/jbc.m114.555177
    Complete structured claim and evidence

What acts on it

  1. NMR and potentiometric titration measured reversible protonation of carnosine, including its imidazole site near physiological pH.

    L-Carnosine / beta-alanyl-L-histidine → Hydrogen ion source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary full text, methods and protonation results
    experimental_model
    Purified dipeptides at 310.15 K and 0.15 M ionic strength.
    limitations
    Chemical buffering does not establish how much a supplement changes exercising muscle pH.
    nutrient_topic
    Carnosine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnosine / beta-alanyl-L-histidine
    plain_language
    Reversible proton binding gives the molecule buffering capacity.
    primary_references
    Species-specific acid-base characterization of carnosine and homocarnosine using nuclear magnetic resonance · 2022 · https://doi.org/10.1016/j.cplett.2022.140128 · DOI 10.1016/j.cplett.2022.140128

    Carnosine: synthesis, transport, carbonyl chemistry and nutrient interactions (2026-09-19) · lines 180–186

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Purified dipeptides at 310.15 K and 0.15 M ionic strength. · source_derived_draft · unverified_draft

    ## carnosine-proton-buffer Reversible proton binding gives the molecule buffering capacity. NMR and potentiometric titration measured reversible protonation of carnosine, including its imidazole site near physiological pH. Model: Purified dipeptides at 310.15 K and 0.15 M ionic strength. Limitations: Chemical buffering does not establish how much a supplement changes exercising muscle pH. Evidence access: Primary full text, methods and protonation results Species-specific acid-base characterization of carnosine and homocarnosine using nuclear magnetic resonance · 2022 · https://doi.org/10.1016/j.cplett.2022.140128 · DOI 10.1016/j.cplett.2022.140128
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. HCl infusion causing acute mineral acidemia raised plasma potassium in the conscious-dog experiment.

    Experimental context and source evidence
    endpoint
    HCl infusion causing acute mineral acidemia raised plasma potassium in the conscious-dog experiment.
    experimental-exposure
    Experimental acute mineral acidemia with hyperkalemia; not potassium deficiency or excessive potassium intake.
    experimental_model
    Twelve conscious dogs with portal/hepatic/systemic sampling; beta-hydroxybutyric acid 7 mEq/kg or HCl 3 mEq/kg infused over 30 minutes; additional anesthetized and obstructed-urinary-tract studies.
    limitations
    Acute HCl infusion, not every acidosis; portal glucagon rose and direct H/K exchange was not isolated.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Canis lupus familiaris
    plain_language
    Acid type affected the potassium response; a rise in blood potassium did not imply excess potassium intake.
    primary_references
    [adrogue-1985-acid-infusion] Role of the endocrine pancreas in the kalemic response to acute metabolic acidosis in conscious dogs (1985). https://www.jci.org/articles/view/111775 DOI: 10.1172/JCI111775
    tissue_or_cell_type
    systemic and splanchnic circulation

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 1151–1162

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Twelve conscious dogs with portal/hepatic/systemic sampling; beta-hydroxybutyric acid 7 mEq/kg or HCl 3 mEq/kg infused over 30 minutes; additional anesthetized and obstructed-urinary-tract studies. · source_derived_draft · unverified_draft

    ### hcl-acidemia-raises-plasma-k HCl infusion causing acute mineral acidemia raised plasma potassium in the conscious-dog experiment. Condition category: normal nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Acid type affected the potassium response; a rise in blood potassium did not imply excess potassium intake. organism: Canis lupus familiaris tissue_or_cell_type: systemic and splanchnic circulation experimental_model: Twelve conscious dogs with portal/hepatic/systemic sampling; beta-hydroxybutyric acid 7 mEq/kg or HCl 3 mEq/kg infused over 30 minutes; additional anesthetized and obstructed-urinary-tract studies. limitations: Acute HCl infusion, not every acidosis; portal glucagon rose and direct H/K exchange was not isolated. experimental-exposure: Experimental acute mineral acidemia with hyperkalemia; not potassium deficiency or excessive potassium intake. endpoint: HCl infusion causing acute mineral acidemia raised plasma potassium in the conscious-dog experiment. [adrogue-1985-acid-infusion] Role of the endocrine pancreas in the kalemic response to acute metabolic acidosis in conscious dogs (1985). https://www.jci.org/articles/view/111775 DOI: 10.1172/JCI111775
    Complete structured claim and evidence
  2. Luminal omeprazole abolished net total-CO2 flux used to measure acidification in collecting ducts from potassium-restricted rabbits.

    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    endpoint
    Luminal omeprazole abolished net total-CO2 flux used to measure acidification in collecting ducts from potassium-restricted rabbits.
    experimental-exposure
    Microperfused inner-stripe outer medullary collecting ducts from rabbits fed 0.55% potassium diet for 7-14 days; luminal omeprazole 0.1 mM.
    experimental_model
    Microperfused inner-stripe outer medullary collecting ducts from rabbits fed 0.55% potassium diet for 7-14 days; luminal omeprazole 0.1 mM.
    limitations
    Pharmacological activity assignment; the experiment does not isolate ATP4A versus ATP12A. Total-CO2 flux is an acidification surrogate.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Oryctolagus cuniculus
    plain_language
    An H/K-pump-compatible activity supported acid secretion in the isolated duct.
    primary_references
    [wingo-1989-hka] Active proton secretion and potassium absorption in the rabbit outer medullary collecting duct. Functional evidence for proton-potassium-activated adenosine triphosphatase (1989). https://pubmed.ncbi.nlm.nih.gov/2544629/ DOI: 10.1172/JCI114165
    tissue_or_cell_type
    inner-stripe outer medullary collecting duct
    transport_direction
    potassium: tubular lumen toward blood; protons: cell toward tubular lumen
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 1096–1108

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Microperfused inner-stripe outer medullary collecting ducts from rabbits fed 0.55% potassium diet for 7-14 days; luminal omeprazole 0.1 mM. · source_derived_draft · unverified_draft

    ### hka-sensitive-proton-secretion Luminal omeprazole abolished net total-CO2 flux used to measure acidification in collecting ducts from potassium-restricted rabbits. Condition category: nutrient_deficiency nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: An H/K-pump-compatible activity supported acid secretion in the isolated duct. organism: Oryctolagus cuniculus tissue_or_cell_type: inner-stripe outer medullary collecting duct experimental_model: Microperfused inner-stripe outer medullary collecting ducts from rabbits fed 0.55% potassium diet for 7-14 days; luminal omeprazole 0.1 mM. limitations: Pharmacological activity assignment; the experiment does not isolate ATP4A versus ATP12A. Total-CO2 flux is an acidification surrogate. transport_direction: potassium: tubular lumen toward blood; protons: cell toward tubular lumen experimental-exposure: Microperfused inner-stripe outer medullary collecting ducts from rabbits fed 0.55% potassium diet for 7-14 days; luminal omeprazole 0.1 mM. endpoint: Luminal omeprazole abolished net total-CO2 flux used to measure acidification in collecting ducts from potassium-restricted rabbits. [wingo-1989-hka] Active proton secretion and potassium absorption in the rabbit outer medullary collecting duct. Functional evidence for proton-potassium-activated adenosine triphosphatase (1989). https://pubmed.ncbi.nlm.nih.gov/2544629/ DOI: 10.1172/JCI114165
    Complete structured claim and evidence
  3. Adding pepsin at 1,200 U/mL under acidic conditions increased egg-yolk cobalamin transfer to human salivary or gastric R binders to 39-58%.

    Experimental context and source evidence
    cross_nutrient
    false
    experimental_model
    In vitro egg-yolk cobalamin-binding protein mixed with human saliva/gastric juice
    exposure
    Pepsin supplementation at acidic pH
    limitations
    Food-specific biochemical model; this pH threshold is not a clinical blood threshold or proof that all foods behave identically. Pepsin preparation species was not specified in the inspected abstract.
    nutrient_topic
    Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
    organism
    Homo sapiens
    plain_language
    Pepsin helped haptocorrin capture food-bound B12.
    primary_references
    [carmel-1990-food-transfer] Transfer of cobalamin from the cobalamin-binding protein of egg yolk to R binder of human saliva and gastric juice. (1990). https://pubmed.ncbi.nlm.nih.gov/2110915/ DOI: 10.1016/0016-5085(90)91076-i
    tissue_or_cell_type
    Gastric luminal digestion model

    Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 101–112

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · In vitro egg-yolk cobalamin-binding protein mixed with human saliva/gastric juice · source_derived_draft · unverified_draft

    ### b12-abs-food-pepsin Adding pepsin at 1,200 U/mL under acidic conditions increased egg-yolk cobalamin transfer to human salivary or gastric R binders to 39-58%. Condition category: normal nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: Pepsin helped haptocorrin capture food-bound B12. organism: Homo sapiens tissue_or_cell_type: Gastric luminal digestion model experimental_model: In vitro egg-yolk cobalamin-binding protein mixed with human saliva/gastric juice limitations: Food-specific biochemical model; this pH threshold is not a clinical blood threshold or proof that all foods behave identically. Pepsin preparation species was not specified in the inspected abstract. exposure: Pepsin supplementation at acidic pH cross_nutrient: false [carmel-1990-food-transfer] Transfer of cobalamin from the cobalamin-binding protein of egg yolk to R binder of human saliva and gastric juice. (1990). https://pubmed.ncbi.nlm.nih.gov/2110915/ DOI: 10.1016/0016-5085(90)91076-i
    Complete structured claim and evidence
  4. Structural analysis of mammalian NNT supported coupling of NADH-to-NADP+ hydride transfer to proton translocation across the mitochondrial membrane.

    Ovine NNT → NADPH source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/niacin-redox-sources/nnt-structure-2019.abstract.txt", "locator": "Indexed abstract, reaction and structural mechanism", "start_char": 199, "end_char": 1759, "file_sha256": "edb35c2cdf2f57d604cb86da48665e5742d398f43c50f3e1622d161564c78a83", "text_sha256": "aa5063e57c35097c2fa2557ed9a7d61c3a411d90d0ded9b947525012520a5712"}
    experimental_model
    Cryo-EM of intact ovine NNT in different nucleotide states
    exposure
    Nucleotide-bound conformational states
    limitations
    Structural mechanism supported in ovine protein; forward flux is context dependent and not equivalent to adding phosphate to NAD. No human intake inference.
    nutrient_topic
    Niacin research collection; topical membership is not evidence of a direct dietary effect. · Niacin (vitamin B3)
    organism
    Ovis aries
    plain_language
    NNT links the NADH and NADPH redox systems through membrane-coupled chemistry.
    primary_references
    [nnt-structure-2019] Structure and mechanism of mitochondrial proton-translocating transhydrogenase. (2019). https://pubmed.ncbi.nlm.nih.gov/31462775/ DOI: 10.1038/s41586-019-1519-2
    tissue_or_cell_type
    Purified mitochondrial protein

    Niacin: NAD metabolism, deficiency and nutrient interactions (2026-09-17) · lines 1003–1014

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cryo-EM of intact ovine NNT in different nucleotide states · source_derived_draft · unverified_draft

    ### b3-redox-nnt-coupling Structural analysis of mammalian NNT supported coupling of NADH-to-NADP+ hydride transfer to proton translocation across the mitochondrial membrane. Condition category: normal nutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect. plain_language: NNT links the NADH and NADPH redox systems through membrane-coupled chemistry. organism: Ovis aries tissue_or_cell_type: Purified mitochondrial protein experimental_model: Cryo-EM of intact ovine NNT in different nucleotide states limitations: Structural mechanism supported in ovine protein; forward flux is context dependent and not equivalent to adding phosphate to NAD. No human intake inference. exposure: Nucleotide-bound conformational states evidence_span: {"source_cache": "artifacts/niacin-redox-sources/nnt-structure-2019.abstract.txt", "locator": "Indexed abstract, reaction and structural mechanism", "start_char": 199, "end_char": 1759, "file_sha256": "edb35c2cdf2f57d604cb86da48665e5742d398f43c50f3e1622d161564c78a83", "text_sha256": "aa5063e57c35097c2fa2557ed9a7d61c3a411d90d0ded9b947525012520a5712"} [nnt-structure-2019] Structure and mechanism of mitochondrial proton-translocating transhydrogenase. (2019). https://pubmed.ncbi.nlm.nih.gov/31462775/ DOI: 10.1038/s41586-019-1519-2
    Complete structured claim and evidence
  5. Human CNDP2 hydrolyzed carnosine only under alkaline assay conditions, with an optimum near pH 9.5.

    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Purified recombinant protein.
    limitations
    Do not assume CNDP2 is an equally active carnosinase at normal cytosolic pH.
    nutrient_topic
    Carnosine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnosine / beta-alanyl-L-histidine
    plain_language
    The similarly named enzyme behaved differently.
    primary_references
    Sequence identification and characterization of human carnosinase and a closely related non-specific dipeptidase. · 2003 · https://pubmed.ncbi.nlm.nih.gov/12473676/ · DOI 10.1074/jbc.M209764200

    Carnosine: synthesis, transport, carbonyl chemistry and nutrient interactions (2026-09-19) · lines 52–58

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Purified recombinant protein. · source_derived_draft · unverified_draft

    ## carnosine-cndp2-ph The similarly named enzyme behaved differently. Human CNDP2 hydrolyzed carnosine only under alkaline assay conditions, with an optimum near pH 9.5. Model: Purified recombinant protein. Limitations: Do not assume CNDP2 is an equally active carnosinase at normal cytosolic pH. Evidence access: Primary abstract Sequence identification and characterization of human carnosinase and a closely related non-specific dipeptidase. · 2003 · https://pubmed.ncbi.nlm.nih.gov/12473676/ · DOI 10.1074/jbc.M209764200
    Complete structured claim and evidence
  6. Carnosine reacted with HNE to form a stabilized Michael adduct and an imine macrocycle in a pH-dependent equilibrium.

    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Buffered chemical reactions; adducts also detected in oxidized rat muscle homogenate.
    limitations
    Reaction chemistry does not measure clinical protection.
    nutrient_topic
    Carnosine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnosine / beta-alanyl-L-histidine
    plain_language
    The peptide can chemically trap a lipid-derived aldehyde.
    primary_references
    Carnosine is a quencher of 4-hydroxy-nonenal: through what mechanism of reaction? · 2002 · https://pubmed.ncbi.nlm.nih.gov/12419310/ · DOI 10.1016/s0006-291x(02)02545-7

    Carnosine: synthesis, transport, carbonyl chemistry and nutrient interactions (2026-09-19) · lines 236–242

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Buffered chemical reactions; adducts also detected in oxidized rat muscle homogenate. · source_derived_draft · unverified_draft

    ## carnosine-hne-adduction The peptide can chemically trap a lipid-derived aldehyde. Carnosine reacted with HNE to form a stabilized Michael adduct and an imine macrocycle in a pH-dependent equilibrium. Model: Buffered chemical reactions; adducts also detected in oxidized rat muscle homogenate. Limitations: Reaction chemistry does not measure clinical protection. Evidence access: Primary abstract Carnosine is a quencher of 4-hydroxy-nonenal: through what mechanism of reaction? · 2002 · https://pubmed.ncbi.nlm.nih.gov/12419310/ · DOI 10.1016/s0006-291x(02)02545-7
    Complete structured claim and evidence
  7. Applying carnosine to oocytes expressing human PEPT1 produced electrogenic proton-coupled transport currents.

    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Human transporter expressed in Xenopus oocytes.
    limitations
    Transporter expression system, not whole-body bioavailability.
    nutrient_topic
    Carnosine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnosine / beta-alanyl-L-histidine
    plain_language
    A peptide transporter can carry intact carnosine.
    primary_references
    The bioactive dipeptide anserine is transported by human proton-coupled peptide transporters. · 2010 · https://pubmed.ncbi.nlm.nih.gov/20067523/ · DOI 10.1111/j.1742-4658.2009.07528.x
    transport_effect
    raises Applying carnosine produced electrogenic proton-coupled inward transport currents.
    transport_pool
    the expressing cell Applying carnosine produced electrogenic proton-coupled inward transport currents.

    Carnosine: synthesis, transport, carbonyl chemistry and nutrient interactions (2026-09-19) · lines 68–74

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Human transporter expressed in Xenopus oocytes. · source_derived_draft · unverified_draft

    ## carnosine-pept1 A peptide transporter can carry intact carnosine. Applying carnosine to oocytes expressing human PEPT1 produced electrogenic proton-coupled transport currents. Model: Human transporter expressed in Xenopus oocytes. Limitations: Transporter expression system, not whole-body bioavailability. Evidence access: Primary abstract The bioactive dipeptide anserine is transported by human proton-coupled peptide transporters. · 2010 · https://pubmed.ncbi.nlm.nih.gov/20067523/ · DOI 10.1111/j.1742-4658.2009.07528.x
    Complete structured claim and evidence
  8. HMIT expressed in Xenopus oocytes mediated electrogenic proton-coupled myo-inositol uptake that increased as pH fell, with maximal tested activity near pH 5.

    Rat Slc2a13 (HMIT) → Myo-inositol source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/inositol-research/11500374.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "fb9efd53bbc0fae1bf1ada1525cdb7d10a4e700d3309bfba4e3a598c4a9c74b9", "start_char": 0, "end_char": 1270, "text_sha256": "fb9efd53bbc0fae1bf1ada1525cdb7d10a4e700d3309bfba4e3a598c4a9c74b9"}
    experimental_model
    Transporter expression and electrophysiology
    exposure
    Extracellular pH manipulation
    limitations
    Transport capacity after heterologous expression does not establish a neuronal plasma-membrane role in vivo.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Rat brain transporter studied in Xenopus oocytes
    plain_language
    A different transporter can use a proton gradient, particularly in acidic experimental conditions.
    primary_references
    [ino-p11500374] Identification of a mammalian H(+)-myo-inositol symporter expressed predominantly in the brain. (2001). https://pubmed.ncbi.nlm.nih.gov/11500374/ DOI: 10.1093/emboj/20.16.4467
    tissue_or_cell_type
    Heterologous membranes and rat brain
    transport_effect
    raises Electrogenic proton-coupled myo-inositol uptake rising as pH fell.
    transport_pool
    the expressing cell Electrogenic proton-coupled myo-inositol uptake rising as pH fell.

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 366–377

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

    ### ino-hmit-acid HMIT expressed in Xenopus oocytes mediated electrogenic proton-coupled myo-inositol uptake that increased as pH fell, with maximal tested activity near pH 5. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: A different transporter can use a proton gradient, particularly in acidic experimental conditions. organism: Rat brain transporter studied in Xenopus oocytes tissue_or_cell_type: Heterologous membranes and rat brain experimental_model: Transporter expression and electrophysiology limitations: Transport capacity after heterologous expression does not establish a neuronal plasma-membrane role in vivo. exposure: Extracellular pH manipulation evidence_span: {"source_cache": "artifacts/inositol-research/11500374.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "fb9efd53bbc0fae1bf1ada1525cdb7d10a4e700d3309bfba4e3a598c4a9c74b9", "start_char": 0, "end_char": 1270, "text_sha256": "fb9efd53bbc0fae1bf1ada1525cdb7d10a4e700d3309bfba4e3a598c4a9c74b9"} [ino-p11500374] Identification of a mammalian H(+)-myo-inositol symporter expressed predominantly in the brain. (2001). https://pubmed.ncbi.nlm.nih.gov/11500374/ DOI: 10.1093/emboj/20.16.4467
    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