2B1M:
reference: Crystal structure of a papain-fold protein without the catalytic residue: a novel member in the cysteine proteinase family., Zhang M, Wei Z, Chang S, Teng M, Gong W, J Mol Biol. 2006 Apr 21;358(1):97-105. Epub 2006 Feb 3. PMID: 16497323

This OCA Structure page
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