5IC4:
reference: Cacidases: caspases can cleave after aspartate, glutamate and phosphoserine residues., Seaman JE, Julien O, Lee PS, Rettenmaier TJ, Thomsen ND, Wells JA, Cell Death Differ. 2016 Jul 1. doi: 10.1038/cdd.2016.62. PMID: 27367566

This OCA Structure page
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