Top surface blade residues and the central channel water molecules are conserved in every repeat of the integrin-like β-propeller structures.

An integrin-like β-propeller domain contains seven repeats of a four-stranded antiparallel β-sheet motif (blades). Previously we described a 3D structural motif within each blade of the integrin-type β-propeller. Here, we show unique structural links that join different blades of the β-propeller structure, which together with the structural motif for a single blade are repeated in a β-propeller to provide the functional top face of the barrel, found to be involved in protein-protein interactions and substrate recognition. We compare functional top face diagrams of the integrin-type β-propeller domain and two non-integrin type β-propeller domains of virginiamycin B lyase and WD Repeat-Containing Protein 5.