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zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"9da1ede1fbf95d6f42d4bb15dc08b5d1869549a7cd94cbfa9da9f9865fd780ff\", \"start_char\": 0, \"end_char\": 2055, \"text_sha256\": \"9da1ede1fbf95d6f42d4bb15dc08b5d1869549a7cd94cbfa9da9f9865fd780ff\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Site-directed mutagenesis of mouse COX-2 residues predicted from comparison of the two isoform crystal structures","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Val-434, Arg-513, Val-523, Val-228 and Gly-533 mutated towards their cyclooxygenase-1 equivalents, then acetylated","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Explains the isoform difference residue by residue. 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Why acetylated COX-1 does not synthesize 15-(R)-hete. 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Murine enzyme, and the L-shaped substrate configuration is an inference from the mutant product profiles.\nexposure: Val-434, Arg-513, Val-523, Val-228 and Gly-533 mutated towards their cyclooxygenase-1 equivalents, then acetylated\nevidence_span: {\"source_cache\": \"artifacts/aspirin-research/10692466.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"9da1ede1fbf95d6f42d4bb15dc08b5d1869549a7cd94cbfa9da9f9865fd780ff\", \"start_char\": 0, \"end_char\": 2055, \"text_sha256\": \"9da1ede1fbf95d6f42d4bb15dc08b5d1869549a7cd94cbfa9da9f9865fd780ff\"}\n[asa-p10692466] Spatial requirements for 15-(R)-hydroxy-5Z,8Z,11Z, 13E-eicosatetraenoic acid synthesis within the cyclooxygenase active site of murine COX-2. Why acetylated COX-1 does not synthesize 15-(R)-hete. 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