New to the CAZy classification? Read this first.
Want to learn more about CAZypedia? Read the CAZypedia 10th anniversary article in Glycobiology.
Glycoside Hydrolase Family 115
Responsible Curator as essentially complete. CAZypedia is a living document, so further improvement of this page is still possible. If you would like to suggest an addition or correction, please contact the page's Responsible Curator directly by e-mail.
|Glycoside Hydrolase Family GH115|
|Active site residues||not known|
|CAZy DB link|
Glycoside hydrolases of GH115 display α-glucuronidase activity. In particular, members of this family catalyze the cleavage of 4-O-methyl D-glucuronic acid sidechains from native xylan polysaccharides (EC 22.214.171.124). In contrast to GH67 enzymes, which only cleave glucuronosyl linkages at the non-reducing ends of xylooligosaccharides, GH115 enzymes remove glucuronic acid from the both terminal and internal regions of xylooligosaccharides and xylans . This substrate specificity was first demonstrated by an α-glucuronidase purified from Thermoascus aurantiacus , and later for a Schizophyllum commune α-glucuronidase . Although GH115 was established on the basis of biochemical and sequence analysis of Pichia stipitis (4-O-methyl)-α-glucuronidase , available N-terminal protein sequence of the S. commune enzyme  allowed the tentative assignment of this enzyme to GH115 , which was later confirmed by the full protein sequence . A GH115 member from Streptomyces pristinaespiralis produces both 4-O-methyl-D-glucuronic acid and non-methylated D-glucuronic acid from xylan and xylo-oligosaccharides .
Kinetics and Mechanism
Using reduced aldopentauronic acid (MeGlcA3Xyl4-ol) as a substrate, analysis by 1H-NMR spectroscopy revealed that the enzymes from both S. commune and P. stipitis release the β-anomer of 4-O-methyl-D-glucuronic acid (MeGlcA) as the first-formed product, thus suggesting a one step, inverting mechanism .
The catalytic residues have not yet been identified in a member of this family.
No 3D structure has been solved for this family at present, although crystallization of a Streptomyces pristinaespiralis homolog has been reported .
- First stereochemistry determination
- Release of the β-anomer of 4-methyl-D-glucuronic acid by both the Schizophyllum commune and Pichia stipitis enzymes using 1H NMR .
- First general acid residue identification
- Not yet identified.
- First general base residue identification
- Not yet identified.
- First 3-D structure
- Crystallization of the Streptomyces pristinaespiralis family member has been reported .
Error fetching PMID 10725538:
Error fetching PMID 19344716:
Error fetching PMID 20804758:
Error fetching PMID 21206027:
Error fetching PMID 21442271:
- Error fetching PMID 19344716:
- Error fetching PMID 2802623:
- Error fetching PMID 10725538:
- Error fetching PMID 21442271:
- Error fetching PMID 21206027:
- Error fetching PMID 20804758: