4UOF:
reference: Structure of nucleoside diphosphate kinase from pacific shrimp (Litopenaeus vannamei) in binary complexes with purine and pyrimidine nucleoside diphosphates., Lopez-Zavala AA, Quintero-Reyes IE, Carrasco-Miranda JS, Stojanoff V, Weichsel A, Rudino-Pinera E, Sotelo-Mundo RR, Acta Crystallogr F Struct Biol Commun. 2014 Sep 1;70(Pt 9):1150-4. doi:, 10.1107/S2053230X1401557X. Epub 2014 Aug 29. PMID: 25195883

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