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(1989). https://pubmed.ncbi.nlm.nih.gov/2788888/","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"ATP-binding region","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"b4afd0b0-7bd5-56b5-ad69-23a2edb2edd0","evidence_kind":"source_excerpt","locator":"Lines 164-175","start_line":164,"end_line":175,"excerpt":"### citrulline-ass1-mg-atp\nMg-ATP almost completely protected human ASS1 against alpha-dicarbonyl inactivation, implicating arginine residues in its binding site.\nCondition category: normal\nnutrient_topic: Citrulline research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The active energy substrate is linked to magnesium, but more magnesium is not automatically rate-limiting.\norganism: Human ASS1\ntissue_or_cell_type: ATP-binding region\nexperimental_model: Chemical modification and substrate protection of enzyme\nlimitations: Protection assay identifies binding requirements; it is not a magnesium supplementation or depletion study.\nexposure: Alpha-dicarbonyl modification with Mg-ATP protection\nevidence_span: {\"source_cache\": \"artifacts/citrulline-research/2788888.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"29b1553359d37a53c529b8a2b53ba646cca6b4b401ba7a9722e0e1f15510e676\", \"start_char\": 0, \"end_char\": 1043, \"text_sha256\": \"29b1553359d37a53c529b8a2b53ba646cca6b4b401ba7a9722e0e1f15510e676\"}\n[citrulline-p2788888] Identification of essential arginine residue(s) for Mg-ATP binding of human argininosuccinate synthetase. 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