This is a helical domain found after the catalytic domain of enzymes from the Glycoside hydrolase family 84 from Bacteroides spp. and certain pathogenic Clostridia spp [1-5].

1: Structure and mechanism of a bacterial beta-glucosaminidase having O-GlcNAcase activity. Dennis RJ, Taylor EJ, Macauley MS, Stubbs KA, Turkenburg JP, Hart SJ, Black GN, Vocadlo DJ, Davies GJ; Nat Struct Mol Biol. 2006;13:365-371. PMID:16565725

2: Inhibition of O-GlcNAcase by a gluco-configured nagstatin and a PUGNAc-imidazole hybrid inhibitor. Shanmugasundaram B, Debowski AW, Dennis RJ, Davies GJ, Vocadlo DJ, Vasella A; Chem Commun (Camb). 2006;42:4372-4374. PMID:17057847

3: Analysis of PUGNAc and NAG-thiazoline as transition state analogues for human O-GlcNAcase: mechanistic and structural insights into inhibitor selectivity and transition state poise. Whitworth GE, Macauley MS, Stubbs KA, Dennis RJ, Taylor EJ, Davies GJ, Greig IR, Vocadlo DJ; J Am Chem Soc. 2007;129:635-644. PMID:17227027

4: A 1-acetamido derivative of 6-epi-valienamine: an inhibitor of a diverse group of beta-N-acetylglucosaminidases. Scaffidi A, Stubbs KA, Dennis RJ, Taylor EJ, Davies GJ, Vocadlo DJ, Stick RV; Org Biomol Chem. 2007;5:3013-3019. PMID:17728868

5: A potent mechanism-inspired O-GlcNAcase inhibitor that blocks phosphorylation of tau in vivo. Yuzwa SA, Macauley MS, Heinonen JE, Shan X, Dennis RJ, He Y, Whitworth GE, Stubbs KA, McEachern EJ, Davies GJ, Vocadlo DJ; Nat Chem Biol. 2008;4:483-490. PMID:18587388