This domain is found at the C-terminal end of Distal tail protein from Lactococcus phage p2 (Dit or Gp15) and similar proteins predominantly found in virus. Dit self-associates as two rings organised back to back, with a central channel allowing DNA ejection through the viral tail. This domain is located at the ring periphery and display a galectin fold [1,2].

1: Structure of lactococcal phage p2 baseplate and its mechanism of activation. Sciara G, Bebeacua C, Bron P, Tremblay D, Ortiz-Lombardia M, Lichiere J, van Heel M, Campanacci V, Moineau S, Cambillau C; Proc Natl Acad Sci U S A. 2010;107:6852-6857. PMID:20351260

2: Structural Insights into Lactococcal Siphophage p2 Baseplate Activation Mechanism. Spinelli S, Tremblay D, Moineau S, Cambillau C, Goulet A; Viruses. 2020; [Epub ahead of print] PMID:32796652