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Recombinant sheep enzyme, not human enzyme in a tissue.\nexposure: Serine 530 replaced with alanine, compared with the native enzyme against aspirin and reversible inhibitors\nevidence_span: {\"source_cache\": \"artifacts/aspirin-research/2108169.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"c7b11508521a3854b432f3836de6e92ba9863c8edb244d747bb1c37634c0bb50\", \"start_char\": 0, \"end_char\": 2076, \"text_sha256\": \"c7b11508521a3854b432f3836de6e92ba9863c8edb244d747bb1c37634c0bb50\"}\n[asa-p2108169] The aspirin and heme-binding sites of ovine and murine prostaglandin endoperoxide synthases. 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