Irreversible binding of T-even bacteriophages to Escherichia coli is mediated by the short and long tail fibres, important for DNA injection. Long tail fibres consist of a phage-proximal (gp34) and a phage-distal rod, the latter containing two protein trimers (gp36 and gp37). Gp36 is present in the upper part of the distal rod, it forms a complex with gp35 and gp37, binding them through the N-terminal and C-terminal regions, respectively. The upper part of the distal rod has a beta-structure [1].

1: Bacteriophage T4 long tail fiber domains. Hyman P, van Raaij M; Biophys Rev. 2018;10:463-471. PMID:29204885