2IWM:
reference: Cloning, preparation and preliminary crystallographic studies of penicillin V acylase autoproteolytic processing mutants., Chandra PM, Brannigan JA, Prabhune A, Pundle A, Turkenburg JP, Dodson GG, Suresh CG, Acta Crystallograph Sect F Struct Biol Cryst Commun. 2005 Jan 1;61(Pt, 1):124-7. Epub 2004 Dec 24. PMID: 16508111

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