4DTB:
reference: Structural Basis for Dual Nucleotide Selectivity of Aminoglycoside 2''-Phosphotransferase IVa Provides Insight on Determinants of Nucleotide Specificity of Aminoglycoside Kinases., Shi K, Berghuis AM, J Biol Chem. 2012 Apr 13;287(16):13094-102. Epub 2012 Feb 24. PMID: 22371504

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