id: Q14032
gene_symbol: BAAT
product_type: PROTEIN
status: INITIALIZED
taxon:
  id: NCBITaxon:9606
  label: Homo sapiens
description: >-
  BAAT is the human bile acid-CoA:amino acid N-acyltransferase (EC 2.3.1.65), the enzyme
  that catalyzes the final conjugation (amidation) step of bile-acid synthesis. It transfers
  the bile acid moiety from its CoA thioester (a bile-acyl-CoA such as choloyl-CoA or
  chenodeoxycholoyl-CoA, generated upstream by the bile acyl-CoA synthetase SLC27A5) onto the
  amino group of glycine or taurine, producing the glyco- and tauro-conjugated bile acids that
  constitute the major secreted and biliary forms. A single monomeric enzyme carries out
  conjugation with both glycine and taurine. Catalysis uses a Cys-235/Asp-328/His-362 charge-relay
  (catalytic triad) characteristic of the C/M/P thioester hydrolase (alpha/beta hydrolase) family,
  with Cys-235 as the nucleophile that forms a covalent bile acid-enzyme intermediate. The same
  active site confers a secondary bile-acyl-CoA thioesterase/hydrolase activity (choloyl-CoA
  hydrolase, EC 3.1.2.27); in vitro the recombinant enzyme also hydrolyzes long- and very
  long-chain acyl-CoAs and conjugates fatty acids to glycine. BAAT is a liver-enriched enzyme
  localized to the peroxisome and the cytosol (endogenous hepatocyte enzyme is predominantly
  peroxisomal, with a cell-type-dependent cytosolic pool). Loss-of-function variants cause
  familial hypercholanemia (FHCA3), an autosomal-recessive bile-acid conjugation defect marked
  by accumulation of unconjugated bile acids, fat malabsorption, fat-soluble-vitamin deficiency,
  and growth failure.
references:
- id: GO_REF:0000002
  title: Gene Ontology annotation through association of InterPro records with GO
    terms
  findings: []
- id: GO_REF:0000024
  title: Manual transfer of experimentally-verified manual GO annotation data to orthologs
    by curator judgment of sequence similarity
  findings: []
- id: GO_REF:0000033
  title: Annotation inferences using phylogenetic trees
  findings: []
- id: GO_REF:0000052
  title: Gene Ontology annotation based on curation of immunofluorescence data
  findings: []
- id: GO_REF:0000107
  title: Automatic transfer of experimentally verified manual GO annotation data to
    orthologs using Ensembl Compara
  findings: []
- id: GO_REF:0000116
  title: Automatic Gene Ontology annotation based on Rhea mapping
  findings: []
- id: GO_REF:0000117
  title: Electronic Gene Ontology annotations created by ARBA machine learning models
  findings: []
- id: GO_REF:0000120
  title: Combined Automated Annotation using Multiple IEA Methods
  findings: []
- id: PMID:12239217
  title: Conserved residues in the putative catalytic triad of human bile acid Coenzyme
    A:amino acid N-acyltransferase.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: >-
      PubMed-verified. Site-directed mutagenesis establishes the Cys-235/Asp-328/His-362
      catalytic triad of hBAT and shows Cys-235-Ser increases the bile acid-CoA thioesterase
      activity; directly supports the N-acyltransferase and thioesterase (choloyl-CoA hydrolase)
      functions.
- id: PMID:12810727
  title: The human bile acid-CoA:amino acid N-acyltransferase functions in the conjugation
    of fatty acids to glycine.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: >-
      PubMed-verified. Recombinant hBACAT conjugates bile acids to glycine/taurine, hydrolyzes
      long/very-long-chain acyl-CoAs (C16-C26) and conjugates fatty acids to glycine in vitro;
      GFP-localization shows mainly cytosolic in fibroblasts.
- id: PMID:17256745
  title: 'Human and rat bile acid-CoA:amino acid N-acyltransferase are liver-specific
    peroxisomal enzymes: implications for intracellular bile salt transport.'
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: >-
      PubMed-verified. Immunofluorescence and digitonin-permeabilization show endogenous human
      and rat BAAT localize specifically to peroxisomes in hepatocytes; cytosolic localization
      seen in fibroblasts. Primary support for peroxisomal (and cell-type-dependent cytosolic)
      location.
- id: PMID:2037576
  title: Purification and characterization of bile acid-CoA:amino acid N-acyltransferase
    from human liver.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: >-
      PubMed-verified. Purification of the human liver enzyme; a single monomeric enzyme
      conjugates bile acids with glycine or taurine; provides kinetic parameters.
- id: PMID:25416956
  title: A proteome-scale map of the human interactome network.
  findings: []
  reference_review:
    relevance: LOW
    correctness: VERIFIED
    review_notes: >-
      PubMed-verified high-throughput binary interactome (HI-II-14 Y2H). Source of a bare
      protein-binding IPI for BAAT (with GOLGA8DP); systematic screen, no BAAT-specific
      functional interpretation.
- id: PMID:32814053
  title: Interactome Mapping Provides a Network of Neurodegenerative Disease Proteins
    and Uncovers Widespread Protein Aggregation in Affected Brains.
  findings: []
  reference_review:
    relevance: LOW
    correctness: VERIFIED
    review_notes: >-
      PubMed-verified neurodegenerative-disease Y2H interactome. Source of multiple bare
      protein-binding IPIs for BAAT; systematic screen with no BAAT-specific functional
      characterization.
- id: PMID:8034703
  title: Glycine and taurine conjugation of bile acids by a single enzyme. Molecular
    cloning and expression of human liver bile acid CoA:amino acid N-acyltransferase.
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: >-
      PubMed-verified. Cloning and expression of hBAT; demonstrates a single cDNA encodes an
      enzyme conjugating cholic acid with both glycine and taurine. Foundational functional
      reference.
- id: file:human/BAAT/BAAT-uniprot.txt
  title: UniProtKB entry BAAT_HUMAN (Q14032)
  findings: []
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: >-
      Curated UniProt/Swiss-Prot record for BAAT; source of the FUNCTION, CATALYTIC ACTIVITY,
      SUBCELLULAR LOCATION, DISEASE (FHCA3), and family (C/M/P thioester hydrolase) statements.
- id: Reactome:R-HSA-159431
  title: Cytosolic chenodeoxycholoyl-CoA or choloyl-CoA are conjugated with glycine
    or taurine
  findings: []
- id: Reactome:R-HSA-192312
  title: Choloyl CoA reacts with glycine or taurine to form glycocholate or taurocholate
  findings: []
- id: Reactome:R-HSA-193368
  title: Synthesis of bile acids and bile salts via 7alpha-hydroxycholesterol
  findings: []
- id: Reactome:R-HSA-193491
  title: Chenodeoxycholoyl CoA reacts with glycine or taurine to form glycochenodeoxycholate
    or taurochenodeoxycholate
  findings: []
- id: Reactome:R-HSA-9033235
  title: Cargo of PEX5S,L translocates from the cytosol to the peroxisomal matrix
  findings: []
- id: Reactome:R-HSA-9033236
  title: PEX5S,L:Cargo binds PEX13:PEX14:PEX2:PEX10:PEX12 (Docking and Translocation
    Module)
  findings: []
existing_annotations:
- term:
    id: GO:0005777
    label: peroxisome
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: is_active_in
  review:
    summary: >-
      Phylogenetic (IBA) inference that BAAT is active in the peroxisome. This is consistent
      with the experimentally-demonstrated peroxisomal localization of endogenous human and rat
      BAAT in hepatocytes.
    action: ACCEPT
    reason: >-
      Peroxisomal localization is directly supported experimentally in this gene
      (PMID:17256745), so the IBA is well grounded.
    supported_by:
    - reference_id: PMID:17256745
      supporting_text: Endogenous hBAAT and rBaat were found to specifically localize to peroxisomes in human and rat hepatocytes, respectively.
- term:
    id: GO:0016747
    label: acyltransferase activity, transferring groups other than amino-acyl groups
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: enables
  review:
    summary: >-
      IBA acyltransferase activity. This is a correct but general parent of the specific
      bile acid-CoA:amino acid N-acyltransferase (glycine N-choloyltransferase) activity of BAAT.
    action: MODIFY
    reason: >-
      The essence is correct but the term is too general. The specific, experimentally
      established molecular function is glycine N-choloyltransferase activity (GO:0047963).
    proposed_replacement_terms:
    - id: GO:0047963
      label: glycine N-choloyltransferase activity
    propagation_review:
      root_cause: TERM_SCOPING_PROBLEM
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: These data demonstrate that a single cDNA is present in human liver which codes for a protein capable of catalyzing the conjugation of cholic acid with both glycine and taurine.
- term:
    id: GO:0008206
    label: bile acid metabolic process
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  review:
    summary: >-
      IBA involvement in bile acid metabolic process. BAAT catalyzes the terminal conjugation
      step of bile-acid metabolism, so this broad process term is correct.
    action: ACCEPT
    reason: >-
      Well supported; BAAT is the bile-acid-conjugating enzyme. This is a correct (if broad)
      process term; the more specific children (bile acid biosynthetic process, bile acid
      conjugation) are also annotated.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: Bile acid-CoA:amino acid N-acyltransferase (BACAT) catalyzes the conjugation of bile acids to glycine and taurine for excretion into bile.
- term:
    id: GO:0006631
    label: fatty acid metabolic process
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  review:
    summary: >-
      IBA involvement in fatty acid metabolic process, reflecting the acyl-CoA
      thioesterase/fatty-acyl-CoA hydrolase side activity of the BAAT/type-I acyl-CoA thioesterase
      family. In vitro BAAT hydrolyzes long/very-long-chain acyl-CoAs and conjugates fatty acids
      to glycine, but a physiological fatty-acid-metabolism role is hypothesized rather than
      established.
    action: KEEP_AS_NON_CORE
    reason: >-
      A defensible family-level inference supported by in vitro activity, but not the core
      physiological function of BAAT (which is bile-acid conjugation). Retain as non-core.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: We show here that recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0) and by mass spectrometry verified that hBACAT also conjugates fatty acids to glycine.
- term:
    id: GO:0006637
    label: acyl-CoA metabolic process
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  review:
    summary: >-
      IBA involvement in acyl-CoA metabolic process. BAAT acts on acyl-CoA thioesters
      (bile-acyl-CoAs and, in vitro, fatty-acyl-CoAs), consuming/hydrolyzing the CoA thioester,
      so this process term is appropriate.
    action: ACCEPT
    reason: >-
      Correct process-level term; BAAT metabolizes acyl-CoA substrates (choloyl-CoA and other
      acyl-CoAs).
    supported_by:
    - reference_id: PMID:12239217
      supporting_text: substantially
        increased the bile acid-CoA thioesterase activity compared with wild type
- term:
    id: GO:0047617
    label: fatty acyl-CoA hydrolase activity
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: enables
  review:
    summary: >-
      IBA fatty acyl-CoA hydrolase activity, reflecting the family-level acyl-CoA thioesterase
      activity. BAAT hydrolyzes acyl-CoA thioesters (choloyl-CoA and, in vitro, long/very-long-chain
      fatty-acyl-CoAs).
    action: KEEP_AS_NON_CORE
    reason: >-
      Correct at the family level and supported by in vitro data, but a secondary activity
      relative to the core bile-acid N-acyltransferase function.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: We show here that recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0005777
    label: peroxisome
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: located_in
  review:
    summary: >-
      Electronic (multi-method) peroxisome localization. Consistent with the experimental
      demonstration of endogenous peroxisomal BAAT in hepatocytes.
    action: ACCEPT
    reason: Corroborated by IDA (PMID:17256745) and IBA/ISS evidence for peroxisomal location.
    supported_by:
    - reference_id: PMID:17256745
      supporting_text: hBAAT and rBaat are peroxisomal enzymes present in undetectable
        amounts in the cytosol.
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: located_in
  review:
    summary: >-
      Electronic cytosol localization. BAAT has a cell-type-dependent cytosolic pool (mainly
      cytosolic in fibroblasts and in historical liver subcellular fractionation).
    action: ACCEPT
    reason: >-
      Supported by IDA evidence for cytosolic localization (HPA; PMID:12810727; PMID:8034703).
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: localization experiments in human skin fibroblasts showed that the hBACAT enzyme
        is mainly cytosolic.
- term:
    id: GO:0006629
    label: lipid metabolic process
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  qualifier: involved_in
  review:
    summary: >-
      ARBA electronic annotation to the very broad "lipid metabolic process". Bile acids and
      fatty acids are lipids, so this is a correct but high-level ancestor term.
    action: KEEP_AS_NON_CORE
    reason: >-
      Too general to be informative and not the core function; correct as a broad ancestor of
      the bile-acid/fatty-acyl-CoA activities. Retain as non-core.
    supported_by:
    - reference_id: file:human/BAAT/BAAT-uniprot.txt
      supporting_text: Fatty acid metabolism; Hydrolase; Lipid metabolism; Peroxisome;
- term:
    id: GO:0006637
    label: acyl-CoA metabolic process
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: involved_in
  review:
    summary: >-
      Electronic acyl-CoA metabolic process annotation (duplicate of the IBA acyl-CoA metabolic
      process). Correct; BAAT acts on acyl-CoA thioester substrates.
    action: ACCEPT
    reason: Correct process term; BAAT consumes/hydrolyzes acyl-CoA thioesters.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0016289
    label: acyl-CoA hydrolase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000116
  qualifier: enables
  review:
    summary: >-
      RHEA-mapped electronic acyl-CoA hydrolase activity. BAAT has an experimentally demonstrated
      acyl-CoA (bile-acyl-CoA) thioesterase/hydrolase activity, so this parent term is correct.
    action: ACCEPT
    reason: >-
      Correct; the bile-acid-CoA thioesterase (choloyl-CoA hydrolase) activity is experimentally
      established (PMID:12239217, PMID:12810727), and additional acyl-CoA hydrolase activity was
      shown in vitro. This is a secondary (non-core) activity but correctly captured.
    supported_by:
    - reference_id: file:human/BAAT/BAAT-uniprot.txt
      supporting_text: May also act as an acyl-CoA thioesterase that
- term:
    id: GO:0016790
    label: thiolester hydrolase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: enables
  review:
    summary: >-
      InterPro-based electronic thiolester hydrolase activity. This is a broad parent of the
      acyl-CoA/choloyl-CoA thioesterase activity of BAAT and reflects the enzyme's membership in
      the C/M/P thioester hydrolase family.
    action: ACCEPT
    reason: >-
      Correct broad hydrolase term consistent with the demonstrated thioesterase activity;
      the more specific children (choloyl-CoA hydrolase, acyl-CoA hydrolase) are also annotated.
    supported_by:
    - reference_id: file:human/BAAT/BAAT-uniprot.txt
      supporting_text: Belongs to the C/M/P thioester hydrolase family.
- term:
    id: GO:0032787
    label: monocarboxylic acid metabolic process
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  qualifier: involved_in
  review:
    summary: >-
      ARBA electronic annotation to monocarboxylic acid metabolic process. Bile acids and fatty
      acids are monocarboxylic acids produced/handled by BAAT, so this broad process term is
      correct but uninformative.
    action: KEEP_AS_NON_CORE
    reason: Correct broad ancestor term; not the core function. Retain as non-core.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0) and by mass spectrometry verified that hBACAT also conjugates fatty acids to glycine
- term:
    id: GO:0033882
    label: choloyl-CoA hydrolase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: enables
  review:
    summary: >-
      Electronic choloyl-CoA hydrolase activity (EC 3.1.2.27). This is the specific bile-acyl-CoA
      thioesterase activity of BAAT and is experimentally established.
    action: ACCEPT
    reason: >-
      Directly supported by experimental data (PMID:12239217, PMID:12810727, PMID:8034703 /
      UniProt EC 3.1.2.27). Secondary but genuine activity.
    supported_by:
    - reference_id: PMID:12239217
      supporting_text: substantially
        increased the bile acid-CoA thioesterase activity compared with wild type
- term:
    id: GO:0047617
    label: fatty acyl-CoA hydrolase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  qualifier: enables
  review:
    summary: >-
      ARBA electronic fatty acyl-CoA hydrolase activity (duplicate of the IBA/IDA fatty-acyl-CoA
      hydrolase annotations). BAAT hydrolyzes fatty-acyl-CoAs in vitro.
    action: KEEP_AS_NON_CORE
    reason: >-
      Supported by in vitro data but a secondary activity relative to bile-acid conjugation.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0047961
    label: glycine N-acyltransferase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000116
  qualifier: enables
  review:
    summary: >-
      RHEA-mapped glycine N-acyltransferase activity, reflecting the demonstrated conjugation of
      fatty acids (and bile acids) to glycine. BAAT conjugates the glycine amino group to acyl-CoA
      substrates.
    action: ACCEPT
    reason: >-
      BAAT transfers acyl groups to glycine (glycine N-choloyltransferase for bile acids; in vitro
      also fatty acids). This is a correct sibling/parent-level N-acyltransferase term; the
      bile-acid-specific child (glycine N-choloyltransferase, GO:0047963) is the core function.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: hBACAT also conjugates fatty
        acids to glycine
- term:
    id: GO:0047963
    label: glycine N-choloyltransferase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: enables
  review:
    summary: >-
      Electronic glycine N-choloyltransferase activity (EC 2.3.1.65) - the defining molecular
      function of BAAT. Corroborates the experimental (EXP/IDA) annotations of the same term.
    action: ACCEPT
    reason: Core molecular function, experimentally established; the electronic annotation is correct.
    supported_by:
    - reference_id: PMID:2037576
      supporting_text: a single monomeric enzyme is responsible for the conjugation of bile acids with glycine
        or taurine in human liver.
- term:
    id: GO:0052815
    label: medium-chain fatty acyl-CoA hydrolase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000116
  qualifier: enables
  review:
    summary: >-
      RHEA-mapped medium-chain fatty acyl-CoA hydrolase activity. BAAT hydrolyzes acyl-CoAs in
      vitro; medium-chain specificity is a narrow electronic inference from Rhea reactions.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      The in vitro acyl-CoA hydrolase activity was reported mainly for long- and very-long-chain
      (C16-C26) acyl-CoAs (PMID:12810727); the medium-chain-specific claim is a fine-grained
      RHEA-derived electronic inference and likely an over-annotation of chain-length specificity.
      The general acyl-CoA hydrolase activity is retained via GO:0016289.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0052816
    label: long-chain fatty acyl-CoA hydrolase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000116
  qualifier: enables
  review:
    summary: >-
      RHEA-mapped long-chain fatty acyl-CoA hydrolase activity, consistent with the in vitro
      hydrolysis of long-chain (C16-C18) acyl-CoAs by recombinant BAAT.
    action: KEEP_AS_NON_CORE
    reason: >-
      Supported by in vitro data (PMID:12810727) but a secondary in-vitro activity, not the core
      physiological function.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0052817
    label: very long-chain fatty acyl-CoA hydrolase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000116
  qualifier: enables
  review:
    summary: >-
      RHEA-mapped very-long-chain fatty acyl-CoA hydrolase activity, consistent with the in vitro
      hydrolysis of very-long-chain (up to C26) acyl-CoAs by recombinant BAAT.
    action: KEEP_AS_NON_CORE
    reason: >-
      Supported by in vitro data (PMID:12810727) but a secondary in-vitro activity, not the core
      physiological function.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:25416956
  qualifier: enables
  review:
    summary: >-
      Bare "protein binding" from a systematic high-throughput binary interactome screen
      (interaction with GOLGA8DP). Uninformative regarding BAAT's molecular function.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      Per curation guidance, "protein binding" is uninformative and this high-throughput
      Y2H interaction has no BAAT-specific functional follow-up; a biologically meaningful
      interaction for an enzyme is not established. Marked as over-annotated rather than removed.
    supported_by:
    - reference_id: PMID:25416956
      supporting_text: a systematic map of ?14,000 high-quality human
        binary protein-protein interactions.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:32814053
  qualifier: enables
  review:
    summary: >-
      Bare "protein binding" from a neurodegenerative-disease-focused Y2H interactome screen
      (multiple partners). Uninformative regarding BAAT's molecular function.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      Per curation guidance, "protein binding" is uninformative; these are high-throughput
      interactome hits without BAAT-specific functional characterization. Marked as
      over-annotated rather than removed.
    supported_by:
    - reference_id: PMID:32814053
      supporting_text: generated by systematic yeast two-hybrid
        interaction screening of
- term:
    id: GO:0001889
    label: liver development
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: involved_in
  review:
    summary: >-
      Electronic annotation transferred from the rat ortholog (Ensembl Compara) to "liver
      development". BAAT is a liver-enriched metabolic enzyme, but there is no evidence that it
      participates in the developmental process of the liver.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      Automatic ortholog-based transfer of a developmental process term. BAAT's role is
      bile-acid conjugation in hepatocytes, not a molecular contribution to liver development;
      likely reflects expression/context rather than function.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: Tissue expression studies showed strong expression of BACAT in
        liver, gallbladder, and the proximal and distal intestine.
- term:
    id: GO:0002152
    label: bile acid conjugation
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: involved_in
  review:
    summary: >-
      Electronic (Ensembl Compara ortholog-transfer) annotation to bile acid conjugation - the
      core biological process of BAAT. Duplicate of the experimental IDA annotations of the same
      term.
    action: ACCEPT
    reason: Core process, experimentally established; the electronic annotation is correct.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: catalyzes the conjugation of
        bile acids to glycine and taurine for excretion into bile.
- term:
    id: GO:0031100
    label: animal organ regeneration
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: involved_in
  review:
    summary: >-
      Electronic annotation transferred from the rat ortholog to "animal organ regeneration".
      This likely reflects differential BAAT expression during liver regeneration in rat rather
      than a molecular function of the enzyme in regeneration.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      Automatic ortholog-based transfer; no evidence that BAAT's catalytic activity contributes
      mechanistically to organ regeneration. Over-annotation of a context/expression observation.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: Tissue expression studies showed strong expression of BACAT in
        liver, gallbladder, and the proximal and distal intestine.
- term:
    id: GO:0016747
    label: acyltransferase activity, transferring groups other than amino-acyl groups
  evidence_type: IDA
  original_reference_id: PMID:12239217
  qualifier: enables
  review:
    summary: >-
      IDA acyltransferase activity from the catalytic-triad mutagenesis study, which directly
      assayed hBAT N-acyltransferase activity. Correct but general.
    action: MODIFY
    reason: >-
      The specific molecular function established in this and other studies is glycine
      N-choloyltransferase (bile acid-CoA:amino acid N-acyltransferase) activity (GO:0047963);
      the general acyltransferase term should be replaced with the specific one.
    proposed_replacement_terms:
    - id: GO:0047963
      label: glycine N-choloyltransferase activity
    supported_by:
    - reference_id: PMID:12239217
      supporting_text: an enzyme catalyzing
        the conjugation of bile acids with the amino acids glycine or taurine
- term:
    id: GO:0006699
    label: bile acid biosynthetic process
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-193368
  qualifier: involved_in
  review:
    summary: >-
      Reactome (TAS) annotation placing BAAT in bile acid biosynthesis. BAAT catalyzes the
      terminal conjugation step of bile-acid synthesis, so this is a core biosynthetic-process
      annotation.
    action: ACCEPT
    reason: >-
      Core process; conjugation is the final step of bile-acid biosynthesis. Also supported by
      experimental IDA (PMID:8034703, PMID:12810727).
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: catalyzes the conjugation of
        bile acids to glycine and taurine for excretion into bile.
- term:
    id: GO:0008206
    label: bile acid metabolic process
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-159431
  qualifier: involved_in
  review:
    summary: >-
      Reactome (TAS) annotation to bile acid metabolic process (duplicate of the IBA). Correct
      broad process term for the bile-acid-conjugating enzyme.
    action: ACCEPT
    reason: Correct broad process; the specific children (biosynthesis, conjugation) are also annotated.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: catalyzes the conjugation of
        bile acids to glycine and taurine for excretion into bile.
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: IDA
  original_reference_id: GO_REF:0000052
  qualifier: located_in
  review:
    summary: >-
      HPA immunofluorescence (IDA) cytosol localization. Consistent with the cell-type-dependent
      cytosolic pool of BAAT reported in the literature.
    action: ACCEPT
    reason: >-
      Supported experimentally; BAAT has a cytosolic pool (mainly cytosolic in fibroblasts and
      historically in liver soluble fractions).
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: localization experiments in human skin fibroblasts showed that the hBACAT enzyme
        is mainly cytosolic.
- term:
    id: GO:0005777
    label: peroxisome
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  qualifier: located_in
  review:
    summary: >-
      ISS peroxisome localization by sequence-similarity transfer from the rat ortholog
      (Q63276). Consistent with experimental peroxisomal localization of human BAAT.
    action: ACCEPT
    reason: Corroborated by direct experimental evidence in human hepatocytes (PMID:17256745).
    supported_by:
    - reference_id: PMID:17256745
      supporting_text: Endogenous hBAAT and rBaat were found to specifically localize to peroxisomes in human and rat hepatocytes, respectively.
- term:
    id: GO:0033882
    label: choloyl-CoA hydrolase activity
  evidence_type: EXP
  original_reference_id: PMID:12239217
  qualifier: enables
  review:
    summary: >-
      Experimental choloyl-CoA (bile acid-CoA) thioesterase/hydrolase activity. The Cys-235-Ser
      mutant showed substantially increased thioesterase activity, directly demonstrating this
      activity for hBAT.
    action: ACCEPT
    reason: >-
      Directly experimentally established secondary activity of BAAT (EC 3.1.2.27). Kept as a
      genuine (secondary) molecular function.
    supported_by:
    - reference_id: PMID:12239217
      supporting_text: substantially
        increased the bile acid-CoA thioesterase activity compared with wild type
- term:
    id: GO:0033882
    label: choloyl-CoA hydrolase activity
  evidence_type: EXP
  original_reference_id: PMID:12810727
  qualifier: enables
  review:
    summary: >-
      Experimental choloyl-CoA/acyl-CoA thioesterase activity from recombinant hBACAT (which
      hydrolyzes long/very-long-chain acyl-CoAs; the family is a type-I acyl-CoA thioesterase).
    action: ACCEPT
    reason: Directly experimentally established secondary thioesterase activity.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: identifying BACAT as a member of the type I acyl-CoA thioesterase gene
        family.
- term:
    id: GO:0033882
    label: choloyl-CoA hydrolase activity
  evidence_type: EXP
  original_reference_id: PMID:8034703
  qualifier: enables
  review:
    summary: >-
      Experimental bile acid-CoA thioesterase (choloyl-CoA hydrolase) activity of purified/cloned
      hBAT. UniProt attributes EC 3.1.2.27 to this reference among others.
    action: ACCEPT
    reason: >-
      Secondary thioesterase activity of BAAT, experimentally supported (UniProt EC 3.1.2.27,
      ECO:0000269|PubMed:8034703).
    supported_by:
    - reference_id: file:human/BAAT/BAAT-uniprot.txt
      supporting_text: May also act as an acyl-CoA thioesterase that
- term:
    id: GO:0047963
    label: glycine N-choloyltransferase activity
  evidence_type: EXP
  original_reference_id: PMID:12239217
  qualifier: enables
  review:
    summary: >-
      Experimental glycine N-choloyltransferase (bile acid-CoA:amino acid N-acyltransferase)
      activity established via catalytic-triad mutagenesis (Cys-235/Asp-328/His-362) of hBAT.
      This is the core molecular function of BAAT.
    action: ACCEPT
    reason: >-
      Core molecular function, directly experimentally established. Catalytic-triad substitutions
      abolish or reduce N-acyltransferase activity.
    supported_by:
    - reference_id: PMID:12239217
      supporting_text: data from this study support the existence of an essential catalytic
        triad within hBAT consisting of Cys-235, His-362, and Asp-328
- term:
    id: GO:0016746
    label: acyltransferase activity
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-159431
  qualifier: enables
  review:
    summary: >-
      Reactome (TAS) general acyltransferase activity. Correct but a general parent of the
      specific bile acid-CoA:amino acid N-acyltransferase function.
    action: MODIFY
    reason: >-
      Too general; the specific molecular function is glycine N-choloyltransferase activity
      (GO:0047963).
    proposed_replacement_terms:
    - id: GO:0047963
      label: glycine N-choloyltransferase activity
    supported_by:
    - reference_id: PMID:2037576
      supporting_text: a single monomeric enzyme is responsible for the conjugation of bile acids with glycine
        or taurine in human liver.
- term:
    id: GO:0016746
    label: acyltransferase activity
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-192312
  qualifier: enables
  review:
    summary: >-
      Reactome (TAS) general acyltransferase activity (choloyl-CoA + glycine/taurine reaction).
      Correct but general.
    action: MODIFY
    reason: Too general; the specific function is glycine N-choloyltransferase activity (GO:0047963).
    proposed_replacement_terms:
    - id: GO:0047963
      label: glycine N-choloyltransferase activity
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: capable of catalyzing the conjugation of cholic acid with both glycine and taurine.
- term:
    id: GO:0016746
    label: acyltransferase activity
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-193491
  qualifier: enables
  review:
    summary: >-
      Reactome (TAS) general acyltransferase activity (chenodeoxycholoyl-CoA + glycine/taurine
      reaction). Correct but general.
    action: MODIFY
    reason: Too general; the specific function is glycine N-choloyltransferase activity (GO:0047963).
    proposed_replacement_terms:
    - id: GO:0047963
      label: glycine N-choloyltransferase activity
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: capable of catalyzing the conjugation of cholic acid with both glycine and taurine.
- term:
    id: GO:0002152
    label: bile acid conjugation
  evidence_type: IDA
  original_reference_id: PMID:2037576
  qualifier: involved_in
  review:
    summary: >-
      IDA bile acid conjugation from purification/characterization of the human liver enzyme,
      which conjugates bile acids with glycine or taurine. Core biological process of BAAT.
    action: ACCEPT
    reason: Core process, directly experimentally established.
    supported_by:
    - reference_id: PMID:2037576
      supporting_text: a single monomeric enzyme is responsible for the conjugation of bile acids with glycine
        or taurine in human liver.
- term:
    id: GO:0047963
    label: glycine N-choloyltransferase activity
  evidence_type: IDA
  original_reference_id: PMID:2037576
  qualifier: enables
  review:
    summary: >-
      IDA glycine N-choloyltransferase activity from the purified human liver enzyme. Core
      molecular function of BAAT.
    action: ACCEPT
    reason: Core molecular function, directly experimentally established.
    supported_by:
    - reference_id: PMID:2037576
      supporting_text: The purified enzyme utilized glycine, taurine, and 2-fluoro-beta-alanine
- term:
    id: GO:0005782
    label: peroxisomal matrix
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-192312
  qualifier: located_in
  review:
    summary: >-
      Reactome (TAS) peroxisomal matrix localization. BAAT is a soluble matrix enzyme imported
      into peroxisomes (PTS-dependent), consistent with matrix (a child of peroxisome) location.
    action: ACCEPT
    reason: >-
      Consistent with experimental peroxisomal localization (PMID:17256745) and PTS-dependent
      peroxisomal import; peroxisomal matrix is an appropriate specific compartment.
    supported_by:
    - reference_id: PMID:17256745
      supporting_text: Endogenous hBAAT and rBaat were found to specifically localize to peroxisomes in human and rat hepatocytes, respectively.
- term:
    id: GO:0005782
    label: peroxisomal matrix
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-193491
  qualifier: located_in
  review:
    summary: >-
      Reactome (TAS) peroxisomal matrix localization (chenodeoxycholoyl-CoA conjugation reaction).
      Consistent with BAAT being a matrix peroxisomal enzyme.
    action: ACCEPT
    reason: Consistent with experimental peroxisomal localization and matrix import.
    supported_by:
    - reference_id: PMID:17256745
      supporting_text: Endogenous hBAAT and rBaat were found to specifically localize to peroxisomes in human and rat hepatocytes, respectively.
- term:
    id: GO:0005782
    label: peroxisomal matrix
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9033235
  qualifier: located_in
  review:
    summary: >-
      Reactome (TAS) peroxisomal matrix localization (peroxisomal protein import). BAAT is a
      PTS-containing cargo imported into the peroxisomal matrix.
    action: ACCEPT
    reason: Consistent with peroxisomal matrix import of BAAT.
    supported_by:
    - reference_id: PMID:17256745
      supporting_text: hBAAT and rBaat are peroxisomal enzymes present in undetectable
        amounts in the cytosol.
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-159431
  qualifier: located_in
  review:
    summary: >-
      Reactome (TAS) cytosol localization (bile acid conjugation reaction placed in the cytosol).
      Consistent with the cytosolic BAAT pool.
    action: ACCEPT
    reason: >-
      Supported by IDA cytosolic localization; Reactome models bile-acid conjugation in the
      cytosol, and a cytosolic BAAT pool is documented.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: the hBACAT enzyme
        is mainly cytosolic.
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9033235
  qualifier: located_in
  review:
    summary: >-
      Reactome (TAS) cytosol localization (peroxisomal import - cargo starts in the cytosol before
      translocation). Consistent with cytosolic BAAT prior to peroxisomal import.
    action: ACCEPT
    reason: Consistent with the documented cytosolic pool of BAAT.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: the hBACAT enzyme
        is mainly cytosolic.
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9033236
  qualifier: located_in
  review:
    summary: >-
      Reactome (TAS) cytosol localization (PEX5 docking of cargo). Consistent with cytosolic BAAT
      prior to peroxisomal import.
    action: ACCEPT
    reason: Consistent with the documented cytosolic pool of BAAT.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: the hBACAT enzyme
        is mainly cytosolic.
- term:
    id: GO:0052815
    label: medium-chain fatty acyl-CoA hydrolase activity
  evidence_type: IDA
  original_reference_id: PMID:12810727
  qualifier: enables
  review:
    summary: >-
      IDA medium-chain fatty acyl-CoA hydrolase activity. The reported in vitro acyl-CoA
      hydrolysis by recombinant BAAT was mainly for long- and very-long-chain (C16-C26) substrates.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      The study emphasized long/very-long-chain (C16-C26) acyl-CoA hydrolysis; a specific
      medium-chain hydrolase claim is at best a minor in-vitro activity and likely an
      over-annotation of chain-length specificity. The general acyl-CoA/choloyl-CoA hydrolase
      activity is retained.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0052816
    label: long-chain fatty acyl-CoA hydrolase activity
  evidence_type: IDA
  original_reference_id: PMID:12810727
  qualifier: enables
  review:
    summary: >-
      IDA long-chain fatty acyl-CoA hydrolase activity, directly supported by the in vitro
      hydrolysis of long-chain (C16-C18) acyl-CoAs by recombinant BAAT.
    action: KEEP_AS_NON_CORE
    reason: >-
      Genuine in vitro activity but secondary to the core bile-acid N-acyltransferase function.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0052817
    label: very long-chain fatty acyl-CoA hydrolase activity
  evidence_type: IDA
  original_reference_id: PMID:12810727
  qualifier: enables
  review:
    summary: >-
      IDA very-long-chain fatty acyl-CoA hydrolase activity, directly supported by the in vitro
      hydrolysis of very-long-chain (up to C26) acyl-CoAs by recombinant BAAT.
    action: KEEP_AS_NON_CORE
    reason: >-
      Genuine in vitro activity but secondary to the core bile-acid N-acyltransferase function;
      may relate to a proposed role in regulating intracellular VLCFA levels.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: important functions also in the regulation of
        intracellular levels of very long-chain fatty acids.
- term:
    id: GO:0005777
    label: peroxisome
  evidence_type: IDA
  original_reference_id: PMID:17256745
  qualifier: located_in
  review:
    summary: >-
      IDA peroxisome localization. Endogenous human BAAT localizes specifically to peroxisomes in
      hepatocytes by immunofluorescence and digitonin-permeabilization. Primary localization evidence.
    action: ACCEPT
    reason: >-
      Direct experimental evidence for peroxisomal localization of endogenous human BAAT. This is
      the strongest localization annotation.
    supported_by:
    - reference_id: PMID:17256745
      supporting_text: Endogenous hBAAT and rBaat were found to specifically localize to peroxisomes in human and rat hepatocytes, respectively.
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: IDA
  original_reference_id: PMID:17256745
  qualifier: located_in
  review:
    summary: >-
      IDA cytosol localization from the same study - GFP-tagged hBAAT localized to the cytosol
      when expressed in fibroblasts, indicating a cell-type-dependent cytosolic pool.
    action: ACCEPT
    reason: >-
      Supported experimentally; BAAT localization is cell-type-dependent, with cytosolic
      localization in fibroblasts (and a cytosolic pool documented in liver fractionation).
    supported_by:
    - reference_id: PMID:17256745
      supporting_text: When expressed in fibroblasts, GFP-tagged hBAAT localized to the cytosol, confirming earlier
        observations.
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: IDA
  original_reference_id: PMID:8034703
  qualifier: located_in
  review:
    summary: >-
      IDA cytosol localization from the cloning/expression study (enzyme activity in the cytosol
      fraction of expressing cells; historically BAAT was recovered from the soluble/cytosolic
      liver fraction).
    action: ACCEPT
    reason: Consistent with the documented cytosolic pool of BAAT.
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: cytosol of Escherichia coli XL1-Blue cells transfected with hBAT8 subcloned into
    - reference_id: PMID:2037576
      supporting_text: purified 480-fold from the soluble fraction of homogenized frozen human
- term:
    id: GO:0006544
    label: glycine metabolic process
  evidence_type: IDA
  original_reference_id: PMID:8034703
  qualifier: involved_in
  review:
    summary: >-
      IDA involvement in glycine metabolic process. BAAT consumes glycine by conjugating it to
      bile acids (and, in vitro, fatty acids), so the enzyme participates in glycine utilization.
    action: KEEP_AS_NON_CORE
    reason: >-
      BAAT uses glycine as a co-substrate, but its core function is bile-acid conjugation rather
      than glycine metabolism per se. Retain as a non-core (co-substrate-based) process annotation.
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: catalyzing the conjugation of cholic acid with both glycine and taurine.
- term:
    id: GO:0006637
    label: acyl-CoA metabolic process
  evidence_type: IDA
  original_reference_id: PMID:12810727
  qualifier: involved_in
  review:
    summary: >-
      IDA involvement in acyl-CoA metabolic process. BAAT metabolizes acyl-CoA thioesters
      (bile-acyl-CoAs and, in vitro, fatty-acyl-CoAs) via its transferase and thioesterase activities.
    action: ACCEPT
    reason: Correct process; BAAT acts directly on acyl-CoA thioester substrates.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
- term:
    id: GO:0006699
    label: bile acid biosynthetic process
  evidence_type: IDA
  original_reference_id: PMID:8034703
  qualifier: involved_in
  review:
    summary: >-
      IDA involvement in bile acid biosynthetic process. Conjugation catalyzed by BAAT is the
      terminal step of bile-acid synthesis in the liver. Core biosynthetic-process annotation.
    action: ACCEPT
    reason: Core process, directly experimentally established.
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: capable of catalyzing the conjugation of cholic acid with both glycine and taurine.
- term:
    id: GO:0019530
    label: taurine metabolic process
  evidence_type: IDA
  original_reference_id: PMID:8034703
  qualifier: involved_in
  review:
    summary: >-
      IDA involvement in taurine metabolic process. BAAT consumes taurine by conjugating it to
      bile acids, participating in taurine utilization.
    action: KEEP_AS_NON_CORE
    reason: >-
      BAAT uses taurine as a co-substrate; its core function is bile-acid conjugation rather than
      taurine metabolism per se. Retain as a non-core (co-substrate-based) process annotation.
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: catalyzing the conjugation of cholic acid with both glycine and taurine.
- term:
    id: GO:0047963
    label: glycine N-choloyltransferase activity
  evidence_type: IDA
  original_reference_id: PMID:12810727
  qualifier: enables
  review:
    summary: >-
      IDA glycine N-choloyltransferase (bile acid-CoA:amino acid N-acyltransferase) activity from
      the recombinant-enzyme study. Core molecular function of BAAT.
    action: ACCEPT
    reason: Core molecular function, directly experimentally established.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: catalyzes the conjugation of
        bile acids to glycine and taurine for excretion into bile.
- term:
    id: GO:0047963
    label: glycine N-choloyltransferase activity
  evidence_type: IDA
  original_reference_id: PMID:8034703
  qualifier: enables
  review:
    summary: >-
      IDA glycine N-choloyltransferase activity from the cloning/expression study, which showed a
      single hBAT enzyme conjugates cholic acid with both glycine and taurine. Core molecular function.
    action: ACCEPT
    reason: Core molecular function, directly experimentally established.
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: capable of catalyzing the conjugation of cholic acid with both glycine and taurine.
- term:
    id: GO:0002152
    label: bile acid conjugation
  evidence_type: IDA
  original_reference_id: PMID:12810727
  qualifier: involved_in
  review:
    summary: >-
      IDA bile acid conjugation from the recombinant-enzyme study. Core biological process of BAAT.
    action: ACCEPT
    reason: Core process, directly experimentally established.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: catalyzes the conjugation of
        bile acids to glycine and taurine for excretion into bile.
- term:
    id: GO:0002152
    label: bile acid conjugation
  evidence_type: IDA
  original_reference_id: PMID:8034703
  qualifier: involved_in
  review:
    summary: >-
      IDA bile acid conjugation from the cloning/expression study. Core biological process of BAAT.
    action: ACCEPT
    reason: Core process, directly experimentally established.
    supported_by:
    - reference_id: PMID:8034703
      supporting_text: capable of catalyzing the conjugation of cholic acid with both glycine and taurine.
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: IDA
  original_reference_id: PMID:12810727
  qualifier: located_in
  review:
    summary: >-
      IDA cytosol localization from GFP-localization in human skin fibroblasts, where hBACAT was
      mainly cytosolic. Consistent with the cell-type-dependent cytosolic pool.
    action: ACCEPT
    reason: Supported experimentally; BAAT is mainly cytosolic in fibroblasts.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: localization experiments in human skin fibroblasts showed that the hBACAT enzyme
        is mainly cytosolic.
- term:
    id: GO:0006699
    label: bile acid biosynthetic process
  evidence_type: IDA
  original_reference_id: PMID:12810727
  qualifier: involved_in
  review:
    summary: >-
      IDA involvement in bile acid biosynthetic process from the recombinant-enzyme study.
      Conjugation is the terminal step of bile-acid synthesis. Core biosynthetic-process annotation.
    action: ACCEPT
    reason: Core process, directly experimentally established.
    supported_by:
    - reference_id: PMID:12810727
      supporting_text: catalyzes the conjugation of
        bile acids to glycine and taurine for excretion into bile.
core_functions:
- description: >-
    Bile acid-CoA:amino acid N-acyltransferase - the terminal, defining catalytic activity of
    BAAT. It transfers the bile acid from its CoA thioester (choloyl-CoA, chenodeoxycholoyl-CoA)
    onto the amino group of glycine (or taurine), producing glyco- and tauro-conjugated bile
    acids, the final step of bile-acid biosynthesis. A single monomeric enzyme conjugates both
    amino acids using a Cys-235/Asp-328/His-362 catalytic triad, with Cys-235 forming a covalent
    bile acid-enzyme intermediate.
  molecular_function:
    id: GO:0047963
    label: glycine N-choloyltransferase activity
  directly_involved_in:
  - id: GO:0006699
    label: bile acid biosynthetic process
  - id: GO:0002152
    label: bile acid conjugation
  - id: GO:0008206
    label: bile acid metabolic process
  locations:
  - id: GO:0005777
    label: peroxisome
  - id: GO:0005829
    label: cytosol
  supported_by:
  - reference_id: PMID:8034703
    supporting_text: capable of catalyzing the conjugation of cholic acid with both glycine and taurine.
  - reference_id: PMID:2037576
    supporting_text: a single monomeric enzyme is responsible for the conjugation of bile acids with glycine
      or taurine in human liver.
  - reference_id: PMID:12239217
    supporting_text: data from this study support the existence of an essential catalytic
      triad within hBAT consisting of Cys-235, His-362, and Asp-328
  - reference_id: PMID:12810727
    supporting_text: catalyzes the conjugation of
      bile acids to glycine and taurine for excretion into bile.
  - reference_id: PMID:17256745
    supporting_text: Endogenous hBAAT and rBaat were found to specifically localize to peroxisomes in human and rat hepatocytes, respectively.
- description: >-
    Secondary bile-acyl-CoA thioesterase (choloyl-CoA hydrolase) activity carried out by the
    same catalytic triad; the Cys-235-Ser substitution reduces N-acyltransferase activity but
    increases thioesterase activity. In vitro the enzyme also hydrolyzes long- and very
    long-chain fatty-acyl-CoAs, consistent with membership in the type-I acyl-CoA thioesterase
    family; a physiological role in regulating intracellular acyl-CoA/VLCFA levels is proposed.
  molecular_function:
    id: GO:0016289
    label: acyl-CoA hydrolase activity
  directly_involved_in:
  - id: GO:0006637
    label: acyl-CoA metabolic process
  locations:
  - id: GO:0005777
    label: peroxisome
  - id: GO:0005829
    label: cytosol
  supported_by:
  - reference_id: PMID:12239217
    supporting_text: substantially
      increased the bile acid-CoA thioesterase activity compared with wild type
  - reference_id: PMID:12810727
    supporting_text: recombinant hBACAT also can hydrolyze long- and very long-chain saturated acyl-CoAs (mainly C16:0-C26:0)
proposed_new_terms: []