4R2I:
reference: Structure-based mutagenesis of STIV B204 reveals essential residues in the virion-associated DNA packaging ATPase., Dellas N, Snyder JC, Dills M, Nicolay SJ, Kerchner KM, Brumfield SK, Lawrence CM, Young MJ, J Virol. 2015 Dec 23. pii: JVI.02435-15. PMID: 26699645

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