Periplasmic xylose-binding component of the ABC-type transport systems that belong to a family of pentose/hexose sugar-binding proteins of the type 1 periplasmic binding protein (PBP1) superfamily, which consists of two alpha/beta globular domains connected by a three-stranded hinge. This Venus flytrap-like domain undergoes a transition from an open to a closed conformational state upon ligand binding. Moreover, the periplasmic xylose-binding protein is homologous to the ligand-binding domain of eukaryotic receptors such as glutamate receptor (GluR) and DNA-binding transcriptional repressors such as LacI and GalR.
Jiyao W et al.(2023). "The conserved domain database in 2023.",