Overall structure of Fbs1 SBD loop-mutant 1. (a) The asymmetric unit contains two Fbs1 SBD loop-mutant 1 molecules (molecule A, red; molecule B, blue). Secondary-structural elements are labelled. The residues of the carbohydrate-binding pocket are depicted as stick models. (b) Overall structure of molecule A. The four loops β2–β3, β5–β6, β7–β8 and β9–β10 are coloured blue, cyan, magenta and yellow, respectively.