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(2025). https://pubmed.ncbi.nlm.nih.gov/40640146/ DOI: 10.1038/s41467-025-61393-x","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"LIAS and H-protein substrate","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"75355633-894c-5d04-bfa3-d3ec4f635641","evidence_kind":"source_excerpt","locator":"Lines 273-284","start_line":273,"end_line":284,"excerpt":"### ala-lias-trapped-intermediate\nCrystallography captured LIAS cross-linked to its H-protein substrate through a 6-mercaptooctanoyl ligand at a [3Fe-4S] cluster.\nCondition category: normal\nnutrient_topic: Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: One sulfur-insertion intermediate temporarily links the enzyme, its iron-sulfur cluster and its substrate.\norganism: Human recombinant proteins\ntissue_or_cell_type: LIAS and H-protein substrate\nexperimental_model: X-ray structures of catalytic stages with human lipoyl synthase\nlimitations: Structural snapshots establish reaction intermediates, not clinical nutrient requirements.\nexposure: Structural trapping of sulfur-insertion intermediates\nevidence_span: {\"source_cache\": \"artifacts/ala-research/40640146.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"292f83149906d0c3be473ce3b23be4ee13d1c662b2665993808021098523cd23\", \"start_char\": 0, \"end_char\": 953, \"text_sha256\": \"292f83149906d0c3be473ce3b23be4ee13d1c662b2665993808021098523cd23\"}\n[ala-p40640146] Structural basis for catalysis by human lipoyl synthase. 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