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Sequence homology is an inference about function, not a demonstration.\nexposure: Expressed epimerase assayed by rate of inversion of R-ibuprofenoyl-CoA\nevidence_span: {\"source_cache\": \"artifacts/ibuprofen-research/9106621.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"d2ece633650b8d636b2d0315b6d6486f618f7aae8a585c54558dffe344edf0cf\", \"start_char\": 0, \"end_char\": 1607, \"text_sha256\": \"d2ece633650b8d636b2d0315b6d6486f618f7aae8a585c54558dffe344edf0cf\"}\n[ibu-p9106621] Molecular cloning and expression of a 2-arylpropionyl-coenzyme A epimerase: a key enzyme in the inversion metabolism of ibuprofen. 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