Neuraminidase Sialidase Protocol The optimal pH for the enzyme is 5.5 to 6.2.



Product No. 11080725001



Neuraminidase (Sialidase) from Vibrio cholerae: Removal of sialic acid from purified lipooligosaccharide (LOS)


The optimal pH for the enzyme is 5.5 to 6.2.

In some cases, it helps to denature the protein to make sites more accessible.

Below are suggested incubation conditions for the deglycosylation of glycoproteins, and denaturation conditions.


The enzyme can be used to cleave sialic acids off proteins:


A mixture of N-glycosidase F, O-glycosidase, and neuraminidase is often used; O-glycans typically have sialized structures which can be hydrolyzed by neuraminidase, and then O-glycosidase can be use to further hydrolyze O-glycans.


A useful enzyme/substrate ratio is approx. 0.04 U/25 - 80 μg.


Combination with O-glucosidase:


When using neuraminidase from Vibrio cholerae, instead of neuraminidase from Arthrobacter, together with O-glycosidase, take into account the pH-optima of O-glycosidase and Vibrio neuraminidase, and work at pH 6 instead of pH 7.2.


Neuraminidase-Sialidase-sialic-acid | China-Mainland | Sigma-Aldrich










Acylneuraminyl hydrolase


Enzymatic Reactions: (images will open in a new window)

2,3-linked Neuraminic acid

2,6-linked Neuraminic acid

2,8-linked Neuraminic acid

Neuraminidase (sialidase) splits off N-acetyl neuraminic acid (sialic acid) from a variety of glycoproteins.




Neuraminidases are important tools for the study of glycoproteins in protein chemistry and cell biology (Hatton et al. 1973).


Worthington neuraminidase is derived from Clostridium perfringens. Chromatographic purification has been developed in this laboratory based on work of Cassidy et al. (1965). Wooley and Gommi (1966) describe the use of this neuraminidase in a method for measuring serotonin receptors. It is also employed to determine bound N-acetylneuraminic acid in tissues.


Characteristics of Neuraminidase from Clostridium perfringens:

Optimum pH: 5.0-5.1 (Burton 1963). Little or no activity at pH 4.0 or above pH 8.0.


Isoelectric point: 5.1 (Groome and Belyaven 1958).


Activators: None, in contrast to the neuraminidase from Vibrio which has a divalent metal requirement.


Inhibitors: Considerable interest has been shown in using neuraminidase inhibitors as possible anti-viral and anti-bacterial agents. (Khorlin et al. 1970; Haskell et al. 1970; and Tute 1970).


Stabilizers: Serum albumin, 0.3 mg/ml (Cassidy et al. 1965).


Stability: The purified preparation is stable for at least two years when stored at 4<C (Cassidy et al. 1965).


Up: Worthington Enzyme Manual



FAQ: Is α2-3,6,8 Neuraminidase active at higher pH levels?

Yes. α2-3,6,8 Neuraminidase has a very broad pH curve. Although optimum pH is around 5.5, we see excellent sialic acid removal at pH's as low as 4.5 and as high as pH 8.5. We have used α2-3,6,8 Neuraminidase at pH ranges more suitable for PNGase F (pH range 7.5-8.6).