This domain can be found in N-acetylglucosamine binding protein (GbpA) from Vibrio cholerae, a bacterial pathogen that colonizes the chitinous exoskeleton of zooplankton as well as the human gastrointestinal tract. GbpA binds to GlcNAc oligosaccharides. Structural comparison show that there are distant structural similarities between domain 2 of GbpA and the beta-domain of the flagellin protein p5. It is suggested that this domain interacts with the bacterial surface, and functions to project an alginate binding domain of the protein from the cell surface [1].

1: The Vibrio cholerae colonization factor GbpA possesses a modular structure that governs binding to different host surfaces. Wong E, Vaaje-Kolstad G, Ghosh A, Hurtado-Guerrero R, Konarev PV, Ibrahim AF, Svergun DI, Eijsink VG, Chatterjee NS, van Aalten DM; PLoS Pathog. 2012;8:e1002373. PMID:22253590