Component

Mitochondrial acetyl-CoA acetyltransferase / ACAT1

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 mitochondrial ACAT1/T2 degraded 2-methylacetoacetyl-CoA by CoA-dependent thiolysis, yielding the isoleucine-branch acetyl-CoA and propionyl-CoA products.

    Mitochondrial acetyl-CoA acetyltransferase / ACAT1 → 2-Methylacetoacetyl-CoA source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Purified human T2 structural/kinetic study; established product chemistry.
    limitations
    ACAT1 here is acetyl-CoA acetyltransferase, not the cholesterol-esterifying SOAT1 enzyme sometimes called ACAT.
    nutrient_topic
    L-Isoleucine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Isoleucine
    plain_language
    One carbon skeleton feeds both an acetyl branch and a propionyl branch.
    primary_references
    Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17371050/ · DOI 10.1021/bi6026192

    L-Isoleucine: transport, translation, catabolism and cross-nutrient mechanisms (2026-09-19) · lines 226–232

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Purified human T2 structural/kinetic study; established product chemistry. · source_derived_draft · unverified_draft

    ## isoleucine-acat1-split One carbon skeleton feeds both an acetyl branch and a propionyl branch. Human mitochondrial ACAT1/T2 degraded 2-methylacetoacetyl-CoA by CoA-dependent thiolysis, yielding the isoleucine-branch acetyl-CoA and propionyl-CoA products. Model: Purified human T2 structural/kinetic study; established product chemistry. Limitations: ACAT1 here is acetyl-CoA acetyltransferase, not the cholesterol-esterifying SOAT1 enzyme sometimes called ACAT. Evidence access: Primary abstract Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17371050/ · DOI 10.1021/bi6026192
    Complete structured claim and evidence

What acts on it

  1. Human T2 structures identified a copurified chloride ion at a high-affinity site near catalytic loops at the dimer interface.

    Chloride ion → Mitochondrial acetyl-CoA acetyltransferase / ACAT1 source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Human T2 crystallography.
    limitations
    Binding-site evidence does not establish dietary chloride limitation or clinical repletion effects.
    nutrient_topic
    L-Isoleucine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Isoleucine
    plain_language
    A second ion occupies a structural site in the same enzyme.
    primary_references
    Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17371050/ · DOI 10.1021/bi6026192

    L-Isoleucine: transport, translation, catabolism and cross-nutrient mechanisms (2026-09-19) · lines 242–248

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human T2 crystallography. · source_derived_draft · unverified_draft

    ## isoleucine-acat1-chloride A second ion occupies a structural site in the same enzyme. Human T2 structures identified a copurified chloride ion at a high-affinity site near catalytic loops at the dimer interface. Model: Human T2 crystallography. Limitations: Binding-site evidence does not establish dietary chloride limitation or clinical repletion effects. Evidence access: Primary abstract Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17371050/ · DOI 10.1021/bi6026192
    Complete structured claim and evidence

  2. Increasing KCl from 0 to 40 mM increased purified human T2 turnover approximately threefold for both acetoacetyl-CoA and 2-methylacetoacetyl-CoA.

    Potassium ion → Mitochondrial acetyl-CoA acetyltransferase / ACAT1 source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Purified human enzyme and potassium-bound structures.
    limitations
    Assay activation is not proof that extra potassium accelerates isoleucine breakdown in a potassium-replete person.
    nutrient_topic
    L-Isoleucine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Isoleucine
    plain_language
    Potassium changed the activity of an enzyme shared by isoleucine and ketone processing.
    primary_references
    Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17371050/ · DOI 10.1021/bi6026192

    L-Isoleucine: transport, translation, catabolism and cross-nutrient mechanisms (2026-09-19) · lines 234–240

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Purified human enzyme and potassium-bound structures. · source_derived_draft · unverified_draft

    ## isoleucine-acat1-potassium Potassium changed the activity of an enzyme shared by isoleucine and ketone processing. Increasing KCl from 0 to 40 mM increased purified human T2 turnover approximately threefold for both acetoacetyl-CoA and 2-methylacetoacetyl-CoA. Model: Purified human enzyme and potassium-bound structures. Limitations: Assay activation is not proof that extra potassium accelerates isoleucine breakdown in a potassium-replete person. Evidence access: Primary abstract Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function. · 2007 · https://pubmed.ncbi.nlm.nih.gov/17371050/ · DOI 10.1021/bi6026192
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Two HSD10 and four ACAT1 deficiency cases shared elevated 2-methyl-3-hydroxybutyrate/tiglylglycine patterns but had different clinical courses.

    Comparison of human HSD10 and ACAT1 deficiencies → Overlapping isoleucine-related urinary organic-acid pattern source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_access
    Primary abstract
    experimental_model
    Six-patient human clinical and molecular study.
    limitations
    Small series; the suggested neurosteroid explanation was not experimentally proven by these comparisons.
    nutrient_topic
    L-Isoleucine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Isoleucine
    plain_language
    Similar metabolite readings can arise from different machinery failures.
    primary_references
    Clinical and molecular analysis of 6 Chinese patients with isoleucine metabolism defects: identification of 3 novel mutations in the HSD17B10 and ACAT1 gene. · 2017 · https://pubmed.ncbi.nlm.nih.gov/28875337/ · DOI 10.1007/s11011-017-0097-y
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    L-Isoleucine: transport, translation, catabolism and cross-nutrient mechanisms (2026-09-19) · lines 250–256

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Six-patient human clinical and molecular study. · source_derived_draft · unverified_draft

    ## isoleucine-catabolic-differential Similar metabolite readings can arise from different machinery failures. Two HSD10 and four ACAT1 deficiency cases shared elevated 2-methyl-3-hydroxybutyrate/tiglylglycine patterns but had different clinical courses. Model: Six-patient human clinical and molecular study. Limitations: Small series; the suggested neurosteroid explanation was not experimentally proven by these comparisons. Evidence access: Primary abstract Clinical and molecular analysis of 6 Chinese patients with isoleucine metabolism defects: identification of 3 novel mutations in the HSD17B10 and ACAT1 gene. · 2017 · https://pubmed.ncbi.nlm.nih.gov/28875337/ · DOI 10.1007/s11011-017-0097-y
    Complete structured claim and evidence

  2. Human mitochondrial acetoacetyl-CoA thiolase ACAT1/T2, a homotetramer, uses coenzyme A to cleave acetoacetyl-CoA into two acetyl-CoA molecules.

    Acetoacetyl-CoA → Acetyl-CoA source_derived_draftungraded
    Experimental context and source evidence
    experimental_model
    Purified recombinant human ACAT1/T2 enzyme kinetics and crystal structures
    limitations
    Thiolase chemistry is reversible and shared with ketone metabolism. These experiments do not measure lysine-specific flux. ACAT1 here denotes acetyl-CoA acetyltransferase, not cholesterol acyltransferase SOAT1.
    organism
    Homo sapiens
    plain_language
    The four-carbon intermediate is split into two acetyl-CoA molecules.
    primary_references
    [haapalainen2007] Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function (2007). https://pubmed.ncbi.nlm.nih.gov/17371050/ DOI: 10.1021/bi6026192
    tissue_or_cell_type
    Mitochondrial matrix enzyme; recombinant protein study

    L-Lysine: mechanism-first literature curation (2026-09-17) · lines 377–385

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified recombinant human ACAT1/T2 enzyme kinetics and crystal structures · source_derived_draft · unverified_draft

    ### acat1-acetoacetyl-coa-thiolysis Human mitochondrial acetoacetyl-CoA thiolase ACAT1/T2, a homotetramer, uses coenzyme A to cleave acetoacetyl-CoA into two acetyl-CoA molecules. Plain language: The four-carbon intermediate is split into two acetyl-CoA molecules. Condition category: normal organism: Homo sapiens tissue_or_cell_type: Mitochondrial matrix enzyme; recombinant protein study experimental_model: Purified recombinant human ACAT1/T2 enzyme kinetics and crystal structures limitations: Thiolase chemistry is reversible and shared with ketone metabolism. These experiments do not measure lysine-specific flux. ACAT1 here denotes acetyl-CoA acetyltransferase, not cholesterol acyltransferase SOAT1. [haapalainen2007] Crystallographic and kinetic studies of human mitochondrial acetoacetyl-CoA thiolase: the importance of potassium and chloride ions for its structure and function (2007). https://pubmed.ncbi.nlm.nih.gov/17371050/ DOI: 10.1021/bi6026192
    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