{"id":"d30cf48e-44bd-5899-8b8c-c9838b1dfd0c","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-hacl1-rat-branched-cleavage","predicate":"cleaves","statement":"Purified rat peroxisomal HACL1 cleaved 2-hydroxy-3-methylhexadecanoyl-CoA into formyl-CoA and 2-methylpentadecanal, with activity dependent on ThDP and Mg2+.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"91bd5fcf-d0ce-5a11-a01e-b76330340b00","mechanism_event_label":"B1 and magnesium support a carbon-cleavage reaction in fatty-acid alpha oxidation. Here the measured products are a one-carbon CoA ester and a shortened aldehyde.","subject":{"id":"fa9ff37b-287c-53c3-89a6-b74ee460f268","slug":"rat-hacl1","display_name":"Rat 2-hydroxyacyl-CoA lyase 1","entity_type_key":"protein"},"object":{"id":"20e7a7e0-480d-5c37-9940-432c6f82bdc2","slug":"2-hydroxy-3-methylhexadecanoyl-coa","display_name":"2-Hydroxy-3-methylhexadecanoyl-CoA","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"91bd5fcf-d0ce-5a11-a01e-b76330340b00","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-hacl1-rat-branched-cleavage-event","event_type":"biochemical_relationship","label":"B1 and magnesium support a carbon-cleavage reaction in fatty-acid alpha oxidation. 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Here the measured products are a one-carbon CoA ester and a shortened aldehyde.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[foulon-1999-hacl1] Purification, molecular cloning, and expression of 2-hydroxyphytanoyl-CoA lyase, a peroxisomal thiamine pyrophosphate-dependent enzyme that catalyzes the carbon-carbon bond cleavage during alpha-oxidation of 3-methyl-branched fatty acids (1999). https://pubmed.ncbi.nlm.nih.gov/10468558/ DOI: 10.1073/pnas.96.18.10039","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Liver peroxisomes","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"d818b30a-15f7-5dce-b251-8636ecc68fd7","evidence_kind":"source_excerpt","locator":"Lines 976-988","start_line":976,"end_line":988,"excerpt":"### b1-hacl1-rat-branched-cleavage\nPurified rat peroxisomal HACL1 cleaved 2-hydroxy-3-methylhexadecanoyl-CoA into formyl-CoA and 2-methylpentadecanal, with activity dependent on ThDP and Mg2+.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: B1 and magnesium support a carbon-cleavage reaction in fatty-acid alpha oxidation. Here the measured products are a one-carbon CoA ester and a shortened aldehyde.\norganism: Rattus norvegicus\ntissue_or_cell_type: Liver peroxisomes\nexperimental_model: Purified rat liver lyase; defined-substrate product identification.\nlimitations: Defined branched substrate and rat purified enzyme; not a human deficiency experiment.\nevidence: [{\"paper_key\": \"foulon-1999-hacl1\", \"source_bundle\": \"artifacts/thiamine_metabolism_sources.json\", \"passage_ids\": [\"abstract\"], \"locator\": \"Primary publication abstract\", \"preservation\": \"Exact text retained in the source bundle; full source document retained when openly retrievable.\"}]\ncross_nutrient: Direct B1/Mg dependence of a lipid-cleavage enzyme; not evidence that dietary Mg universally limits alpha oxidation.\nnutrient: Thiamine (vitamin B1)\n[foulon-1999-hacl1] Purification, molecular cloning, and expression of 2-hydroxyphytanoyl-CoA lyase, a peroxisomal thiamine pyrophosphate-dependent enzyme that catalyzes the carbon-carbon bond cleavage during alpha-oxidation of 3-methyl-branched fatty acids (1999). https://pubmed.ncbi.nlm.nih.gov/10468558/ DOI: 10.1073/pnas.96.18.10039","model_system":"Purified rat liver lyase; defined-substrate product identification.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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