3FZB:
reference: The X-Ray Crystal Structure of the Phage lambda Tail Terminator Protein Reveals the Biologically Relevant Hexameric Ring Structure and Demonstrates a Conserved Mechanism of Tail Termination among Diverse Long-Tailed Phages., Pell LG, Liu A, Edmonds L, Donaldson LW, Howell PL, Davidson AR, J Mol Biol. 2009 May 6. PMID: 19426744

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