BNR/Asp-box repeat
BNR/Asp-box repeat is a repetitive sequence of amino acids contained in some proteins. Many of these proteins contain multiple BNR repeats or Asp-boxes.
The repeats are short, however the repeats are never found closer than 40 residues together suggesting that the repeat is structurally longer. The Asp-box itself adopts a well-defined beta-hairpin fold. These repeats are found in a variety of non-homologous proteins, including bacterial ribonucleases, sulphite oxidases, reelin, netrins, sialidases, neuraminidases, some lipoprotein receptors, and a variety of glycosyl hydrolases.