Crystal structure of native β-N-acetylhexosaminidase isolated from Aspergillus oryzae sheds light onto its substrate specificity, high stability, and regulation by propeptide
Language English Country England, Great Britain Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
29239122
DOI
10.1111/febs.14360
Knihovny.cz E-resources
- Keywords
- X-ray crystallography, active pocket, carbohydrate biotechnology, glycosylation, mass spectrometry, propeptide,
- MeSH
- Aspergillus oryzae enzymology MeSH
- beta-N-Acetylhexosaminidases chemistry metabolism MeSH
- Dimerization MeSH
- Fungal Proteins chemistry metabolism MeSH
- G(M2) Activator Protein chemistry metabolism MeSH
- G(M2) Ganglioside chemistry metabolism MeSH
- Glycosylation MeSH
- Protein Interaction Domains and Motifs MeSH
- Catalytic Domain MeSH
- Conserved Sequence MeSH
- Crystallography, X-Ray MeSH
- Ligands MeSH
- Models, Molecular * MeSH
- Protein Processing, Post-Translational MeSH
- Enzyme Precursors chemistry metabolism MeSH
- Amino Acid Sequence MeSH
- Sequence Alignment MeSH
- Protein Stability MeSH
- Structural Homology, Protein MeSH
- Substrate Specificity MeSH
- Binding Sites MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- beta-N-Acetylhexosaminidases MeSH
- Fungal Proteins MeSH
- G(M2) Activator Protein MeSH
- G(M2) Ganglioside MeSH
- Ligands MeSH
- Enzyme Precursors MeSH
UNLABELLED: β-N-acetylhexosaminidase from the fungus Aspergillus oryzae is a secreted extracellular enzyme that cleaves chitobiose into constituent monosaccharides. It belongs to the GH 20 glycoside hydrolase family and consists of two N-glycosylated catalytic cores noncovalently associated with two 10-kDa O-glycosylated propeptides. We used X-ray diffraction and mass spectrometry to determine the structure of A. oryzae β-N-acetylhexosaminidase isolated from its natural source. The three-dimensional structure determined and refined to a resolution of 2.3 Å revealed that this enzyme is active as a uniquely tight dimeric assembly further stabilized by N- and O-glycosylation. The propeptide from one subunit forms extensive noncovalent interactions with the catalytic core of the second subunit in the dimer, and this chain swap suggests the distinctive structural mechanism of the enzyme's activation. Unique structural features of β-N-acetylhexosaminidase from A. oryzae define a very stable and robust framework suitable for biotechnological applications. The crystal structure reported here provides structural insights into the enzyme architecture as well as the detailed configuration of the active site. These insights can be applied to rational enzyme engineering. DATABASE: Structural data are available in the PDB database under the accession number 5OAR. ENZYME: β-N-acetylhexosaminidase (EC 3.2.1.52).
Department of Biochemistry Faculty of Science Charles University Prague Czech Republic
Institute of Microbiology The Czech Academy of Sciences Prague Czech Republic
Institute of Molecular Genetics The Czech Academy of Sciences Prague Czech Republic
Institute of Organic Chemistry and Biochemistry The Czech Academy of Sciences Prague Czech Republic
Institute of Physics Faculty of Mathematics and Physics Charles University Prague Czech Republic
References provided by Crossref.org
Acceptor Specificity of β-N-Acetylhexosaminidase from Talaromyces flavus: A Rational Explanation
