2K4Q:
reference: The phage lambda major tail protein structure reveals a common evolution for long-tailed phages and the type VI bacterial secretion system., Pell LG, Kanelis V, Donaldson LW, Howell PL, Davidson AR, Proc Natl Acad Sci U S A. 2009 Mar 17;106(11):4160-5. Epub 2009 Feb 27. PMID: 19251647

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).