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(1998). https://pubmed.ncbi.nlm.nih.gov/9514741/ DOI: 10.1006/jmbi.1997.1583","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Mitochondrial ornithine transamination","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"757b353c-0ec8-58d4-85bc-2b8ed6ee2913","evidence_kind":"source_excerpt","locator":"Lines 333-344","start_line":333,"end_line":344,"excerpt":"### citrulline-oat-plp\nHuman OAT bound pyridoxal phosphate through a Schiff base to Lys292.\nCondition category: normal\nnutrient_topic: Citrulline research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Vitamin B6 has a defined role in the machinery handling ornithine.\norganism: Human OAT\ntissue_or_cell_type: Mitochondrial ornithine transamination\nexperimental_model: Recombinant enzyme crystal structure\nlimitations: The described reaction direction is ornithine transamination; this structure alone does not quantify reverse flux in human intestine.\nexposure: PLP-bound enzyme structure\nevidence_span: {\"source_cache\": \"artifacts/citrulline-research/9514741.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"cca17abd35f0211a043dd3cc8883369e230209206ff62b62242197f90201cea0\", \"start_char\": 0, \"end_char\": 2979, \"text_sha256\": \"cca17abd35f0211a043dd3cc8883369e230209206ff62b62242197f90201cea0\"}\n[citrulline-p9514741] Crystal structure of human recombinant ornithine aminotransferase. 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