Description
General description
Neuraminidase enzymes are glycoside hydrolase enzymes that catalyze hydrolysis of terminal sialic acid residues. The most well-known are the viral nearamidases, which promote influenza virus release.
Application
Neuraminidase from Clostridium perfringens has been used in a study to assess the binding characteristics of iota toxin by fluorescence-activated cytometry. It has also been used in a study to investigate the distribution of neuraminidase among food poisoning strains.
Biochem/physiol Actions
Neuraminidase cleavage of sialic acid groups has been used to study recognition by antibodies of glycoprotein structures. The use of neuraminidase in the estimation of N-acetylneuraminic acid was compared favorably to two other methods.
Neuraminidases are used to cleave terminal N-acetyl neuraminic acid (sialic acid) from a variety of glycoproteins. The enzyme from Clostridium perfringens cleaves terminal sialic acid residues which are α-2,3- α-2,6- or α-2,8-linked to Gal, GlcNac, GalNAc, AcNeu, GlcNeu, oligosaccharides, glycolipids or glycoproteins. The relative rate of cleavage decreases in the order: α-2-3 > α-2-6 . α-2-8. Neuraminidase from C. perfringens cleaves α-2-3 linked sialic acid residues most efficiently, compared to A. ureafaciens, (Sigma N3642) which preferentially cleaves α-2-6 linked residues.
The degradation of gangliosides grown in lipid mono layers by Clostridium perfringens neuraminidase depends largely on surface pressure. Increased pressure can inhibit neuraminidase activity.
The use of neuraminidase to remove sialic acid residues from glycoproteins on cell surfaces has been frequently reported. Generally, procedures have indicated using neuraminidase in PBS at 37°C for 30 minutes, followed by several washings with PBS. Treatment of tissue sections with neuraminidase at much lower concentrations require longer incubation: for 1-4 U/mL in 0.1 M acetate buffer pH 4.2-5, from 2 to 20 hours at 37 °C.
Preparation Note
Chromatographically purified from Type V (N 2876)
Analysis Note
Package sizes based on 4MU-NANA units
Package sizes based on the 4MU-NANA units
Other Notes
One unit will liberate 1.0 micromole of N-acetyl neuraminic acid per minute at pH 5.0 at 37 °C using bovine submaxillary mucin.
One unit will hydrolyze 1.0 micromole of 2′-(4-methylumbelliferyl)-a-D-N-actetylneuraminic acid per minute at pH 5.0 at 37 °C (using 4MU-NANA as a substrate)
