Description
This enzyme releases non-reducing terminal β1-2, β1-3, β1-4 and β1-6 linked N-acetylglucosamine from complex carbohydrates. When incubated with oligosaccharides at low concentrations (<50 mU/ml) the enzyme can differentiate between GlcNAcβ1-2Man, GlcNAcβ1-4Man and GlcNAcβ1-6Man linkages. Under such conditions, the enzyme cleaves essentially only β1-2 linked GlcNAc, with two provisos. Firstly, β1-2 GlcNAc is not hydrolyzed if the mannose to which it is substituted has a substitution at C-6. Thus, the enzyme is useful for the analysis of tri-antennary oligosaccharides. Secondly, if the β-linked mannose of the conserved pentasaccharide core is substituted with a "bisecting" GlcNAc then only the β1-2 linked GlcNAc linked to mannose on the α1-3 arm is cleaved. At higher concentrations of the enzyme, β1-4 and β1-6 linked GlcNAc may also be hydrolyzed.
Abbr
β-N-Acetylhexosaminidase, Recombinant (Prokaryote)
Applications
For use in glycobiology research.
Form
In 3.2 M ammonium sulphate.
Enzyme Commission Number
EC 3.2.1.52
Activity
~ 260 U/mg protein (on pNP-β-D-N-acetylglucosamine) at pH 4.0 and 40°C; ~ 723 U/mg protein (on pNP-β-D-N-acetylglucosamine) at pH 4.0 and 60°C.
Molecular Weight
~ 52,000
Specificity
Hydrolysis of terminal non-reducing N-acetyl-D-hexosamine residues in N-acetyl-β-Dhexosaminides from glycoproteins and oligosaccharides.
Unit Definition
One Unit of β-N-acetyl-D-hexosaminidase activity is defined as the amount of enzyme required to release one µmole of p-nitrophenol per minute from pNP-β-D-N-acetylglucosamine (1 mM) in Citrate-phosphate buffer (100 mM) pH 4.0 at the temperatures indicated, monitored at 400 nm.
Thermal stability
up to 50°C
Stability
> 2 years at 4°C.
Preparation Instructions
For assay, this enzyme should be diluted in Citratephosphate buffer (100 mM), pH 4.0 containing 1 mg/mL BSA. Swirl to mix the enzyme immediately prior to use.
Synonyms
beta-N-acetyl-D-hexosaminide; N-acetylhexosaminohydrolase; β-N-Acetylhexosaminidase; N-Acetyl-β-D-glucosaminidase, β-N-Acetylglucosaminidase