3AQJ:
reference: The host-binding domain of the P2 phage tail spike reveals a trimeric iron-binding structure., Yamashita E, Nakagawa A, Takahashi J, Tsunoda K, Yamada S, Takeda S, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011 Aug 1;67(Pt 8):837-41., Epub 2011 Jul 13. PMID: 21821878

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