1SQ6:
reference: Structures of Plasmodium falciparum purine nucleoside phosphorylase complexed with sulfate and its natural substrate inosine., Schnick C, Robien MA, Brzozowski AM, Dodson EJ, Murshudov GN, Anderson L, Luft JR, Mehlin C, Hol WG, Brannigan JA, Wilkinson AJ, Acta Crystallogr D Biol Crystallogr. 2005 Sep;61(Pt 9):1245-54. Epub 2005, Aug 16. PMID: 16131758

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