You should know the mass of the protein based on the amino acid sequence. If you measure the mass of the glycosylated protein, you will see how much the mass is increased by glycosylation. It is often the case that glycosylation is heterogeneous, so you will probably see a broad band on SDS-PAGE and a mixture of species by mass spectrometry. If you don't know the amino acid sequence of the protein, treat it with enyzmes to remove the glycosylation and measure the mass of the deglycosylated protein.

https://www.neb.com/products/p6039-protein-deglycosylation-mix#pd-description

Could you please give us more information ? Have you an isolated protein or a mixture, are you able to revealed it easily with in-gel staining or should you use secondary staining (blot and stain or antibodies).

Thereafter some ideas and we will continue after your feedback:

If initially you do not know at all the composition of the glycan part, one possibility is to use lectin probes to characterize the type of glycosylation (some lectins recognize for example the Man residues of N-linked glycans) before use deglycosylation enzymes.

You can have an estimate of the molecular mass of your protein by SDS-PAGE, but if the protein is highly glycosylated you should adjust the polyacrylamide composition since the apparent molecular mass will change according to the composition. So you could start by using two different polyacrylamide concentrations, e.g. 7.5% and 20% and estimate the molecular mass: if no particular difference, this means that the protein has low glycan content.

This protien has plant protein of native molecular mass of 360 kda and comprised of heteromer of 37 and 40 kda.. It give two band on SDS page.. In literature it is mentioned that this kind of protein is heavily glycosilated (30%). I want some simple prosidure to know how much my protein is glycosilated.. Cold I use protease and degrate protein then estimate the sugar content or should I cleave glycosilated moities and then estimate the difference of mass in SDS page?

If the protein is purified, the easiest way is to directly estimate sugar content by monosaccharide analysis using GLC or HPLC

protein is purified.. please elaborate that how i check it through HPLC?

Starting from a known amount of protein, you should hydrolyse it to release the monosaccharides, then quantify them.

Have a look to this link, you will find valuable ideas :

https://books.google.fr/books?hl=fr&lr=&id=F8fUJ_6ULeoC&oi=fnd&pg=PA31&dq=analysis+of+monosaccharides+by+GLC+and+HPLC&ots=9x0KNmT5mG&sig=6qpQbvbhCHVi2BZ1ocA-C17vsYc#v=onepage&q=analysis%20of%20monosaccharides%20by%20GLC%20and%20HPLC&f=false

 Thank you sir..

Please read the article below for the latest guidance on carbohydrate analysis.

K. R. Anumula. (2014) Single Tag for Total Carbohydrate Analysis. Anal. Biochem. 457, 31-37. (Review Article).

 Thanku Mr. Anumula

There are two steps involved in determining quantity of glycosylation of a protein. Since molecule weight of your protein is already known you know the  and do the deglycosylation and measure the mass. 

i) chemical deglycosylation works better with Hydrazine or trifluoromethanesulphonic acid 

ii) Mass of the protein can be done with MALDI-TOF

if you are interested contact us using the following link.

http://www.ccamp.res.in/glycomics