This domain is found at the N-terminal end of Glucosidase YgjK from Escherichia coli and similar bacterial enzymes from the glycoside hydrolase family 63 (GH63) from bacteria, archaea, and eukaryotes. YgjK is organised into N- and A- domains and a linker between them. This entry includes the N-domain and the linker. The N-domain is composed of 18 antiparallel beta-strands divided into two beta- sheets and is classified as a super-beta-sandwich. The linker is composed of two helices and produces a significant curvature between the two domains [1-3].

1: Structural insights into the substrate specificity and function of Escherichia coli K12 YgjK, a glucosidase belonging to the glycoside hydrolase family 63. Kurakata Y, Uechi A, Yoshida H, Kamitori S, Sakano Y, Nishikawa A, Tonozuka T; J Mol Biol. 2008;381:116-128. PMID:18586271

2: Structure of a bacterial glycoside hydrolase family 63 enzyme in complex with its glycosynthase product, and insights into the substrate specificity. Miyazaki T, Ichikawa M, Yokoi G, Kitaoka M, Mori H, Kitano Y, Nishikawa A, Tonozuka T; FEBS J. 2013;280:4560-4571. PMID:23826932

3: Megabodies expand the nanobody toolkit for protein structure determination by single-particle cryo-EM. Uchanski T, Masiulis S, Fischer B, Kalichuk V, Lopez-Sanchez U, Zarkadas E, Weckener M, Sente A, Ward P, Wohlkonig A, Zogg T, Remaut H, Naismith JH, Nury H, Vranken W, Aricescu AR, Pardon E, Steyaert J; Nat Methods. 2021;18:60-68. PMID:33408403