2FAW:
reference: Crystal structure of papaya glutaminyl cyclase, an archetype for plant and bacterial glutaminyl cyclases., Wintjens R, Belrhali H, Clantin B, Azarkan M, Bompard C, Baeyens-Volant D, Looze Y, Villeret V, J Mol Biol. 2006 Mar 24;357(2):457-70. Epub 2006 Jan 4. PMID: 16438985

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