This domain is found in Tail spike protein (TSP) from Shigella phage Sf6 and similar sequences from tailed bacteriophages and bacterial prophages. It forms a beta-sandwich formed by two antiparallel, three stranded beta-sheets. A short alpha helix is included in the connecting loop between the third and fourth strand. This domain is structurally homologous to viral coat proteins [1].

1: An intersubunit active site between supercoiled parallel beta helices in the trimeric tailspike endorhamnosidase of Shigella flexneri Phage Sf6. Muller JJ, Barbirz S, Heinle K, Freiberg A, Seckler R, Heinemann U; Structure. 2008;16:766-775. PMID:18462681

2: The O-specific polysaccharide lyase from the phage LKA1 tailspike reduces Pseudomonas virulence. Olszak T, Shneider MM, Latka A, Maciejewska B, Browning C, Sycheva LV, Cornelissen A, Danis-Wlodarczyk K, Senchenkova SN, Shashkov AS, Gula G, Arabski M, Wasik S, Miroshnikov KA, Lavigne R, Leiman PG, Knirel YA, Drulis-Kawa Z; Sci Rep. 2017;7:16302. PMID:29176754

3: Bacteriophage Tailspikes and Bacterial O-Antigens as a Model System to Study Weak-Affinity Protein-Polysaccharide Interactions. Kang Y, Gohlke U, Engstrom O, Hamark C, Scheidt T, Kunstmann S, Heinemann U, Widmalm G, Santer M, Barbirz S; J Am Chem Soc. 2016;138:9109-9118. PMID:27045683

4: Structural basis for fragmenting the exopolysaccharide of Acinetobacter baumannii by bacteriophage PhiAB6 tailspike protein. Lee IM, Tu IF, Yang FL, Ko TP, Liao JH, Lin NT, Wu CY, Ren CT, Wang AH, Chang CM, Huang KF, Wu SH; Sci Rep. 2017;7:42711. PMID:28209973