2P4S:
reference: Anopheles gambiae purine nucleoside phosphorylase: catalysis, structure, and inhibition., Taylor EA, Rinaldo-Matthis A, Li L, Ghanem M, Hazleton KZ, Cassera MB, Almo SC, Schramm VL, Biochemistry. 2007 Oct 30;46(43):12405-15. Epub 2007 Oct 6. PMID: 17918964

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