2AQO:
reference: Functional significance of Glu-77 and Tyr-137 within the active site of isoaspartyl dipeptidase., Marti-Arbona R, Thoden JB, Holden HM, Raushel FM, Bioorg Chem 2005 Dec;33(6):448-58. Epub 2005 Nov 11. PMID: 16289685

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