| 1CQS: reference: Asp-99 donates a hydrogen bond not to Tyr-14 but to the steroid directly in the catalytic mechanism of Delta 5-3-ketosteroid isomerase from Pseudomonas putida biotype B., Choi G, Ha NC, Kim SW, Kim DH, Park S, Oh BH, Choi KY, Biochemistry 2000 Feb 8;39(5):903-9. PMID: 10653633 |
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