1XE3:
reference: Structure of purine nucleoside phosphorylase (DeoD) from Bacillus anthracis., Grenha R, Levdikov VM, Fogg MJ, Blagova EV, Brannigan JA, Wilkinson AJ, Wilson KS, Acta Crystallograph Sect F Struct Biol Cryst Commun. 2005 May 1;61(Pt, 5):459-62. Epub 2005 Apr 9. PMID: 16511068

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