This is the catalytic region of the superfamily of enzymes referred to as GH36. UniProtKB:Q76IQ9 is a chitobiose phosphorylase that catalyses the reversible phosphorolysis of chitobiose into alpha-GlcNAc-1-phosphate and GlcNAc with inversion of the anomeric configuration. The full-length enzyme comprises a beta sandwich domain and an (alpha/alpha)(6) barrel domain. The alpha-helical barrel component of the domain, this family, is the catalytic region [1].

1: Chitobiose phosphorylase from Vibrio proteolyticus, a member of glycosyl transferase family 36, has a clan GH-L-like (alpha/alpha)(6) barrel fold. Hidaka M, Honda Y, Kitaoka M, Nirasawa S, Hayashi K, Wakagi T, Shoun H, Fushinobu S; Structure. 2004;12:937-947. PMID:15274915