3TDW:
reference: Aminoglycoside-2" phosphotransferase-IIIa (APH(2")-IIIa) prefers GTP over ATP: Structural templates for nucleotide recognition in the bacterial aminoglycoside-2" kinases., Smith CA, Toth M, Frase H, Byrnes LJ, Vakulenko SB, J Biol Chem. 2012 Feb 24. PMID: 22367198

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