1NDP:
reference: Adenosine 5'-diphosphate binding and the active site of nucleoside diphosphate kinase., Morera S, Lascu I, Dumas C, LeBras G, Briozzo P, Veron M, Janin J, Biochemistry 1994 Jan 18;33(2):459-67. PMID: 8286376

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