Alpha-N-acetylglucosaminidase, a lysosomal enzyme required for the stepwise degradation of heparan sulfate [1]. Mutations on the alpha-N-acetylglucosaminidase (NAGLU) gene can lead to Mucopolysaccharidosis type IIIB (MPS IIIB; or Sanfilippo syndrome type B) characterised by neurological dysfunction but relatively mild somatic manifestations [2]. The structure shows that the enzyme is composed of three domains. This C-terminal domain has an all alpha helical fold [3].

1: Mouse model of Sanfilippo syndrome type B produced by targeted disruption of the gene encoding alpha-N-acetylglucosaminidase. Li HH, Yu WH, Rozengurt N, Zhao HZ, Lyons KM, Anagnostaras S, Fanselow MS, Suzuki K, Vanier MT, Neufeld EF; Proc Natl Acad Sci U S A 1999;96:14505-14510. PMID:10588735

2: Correction of mucopolysaccharidosis type IIIb fibroblasts by lentiviral vector-mediated gene transfer. Villani GR, Follenzi A, Vanacore B, Di Domenico C, Naldini L, Di Natale P; Biochem J 2002;364:747-753. PMID:12049639

3: Structural and mechanistic insight into the basis of mucopolysaccharidosis IIIB. Ficko-Blean E, Stubbs KA, Nemirovsky O, Vocadlo DJ, Boraston AB; Proc Natl Acad Sci U S A. 2008;105:6560-6565. PMID:18443291