QA-Bio PNGase F Denatured Glycoprotein Protocol v1

PNGase F cleaves N-linked (asparagine-linked) oligosaccharides from glycoproteins. The enzyme deaminates asparagine to aspartic acid, leaving the oligosaccharides intact. Denaturation increases the rate of cleavage. Most native proteins can still be completely N-deglycosylated but incubation time must be increased. The enzyme will remain fully active under reaction conditions (37˚C) for at least 96 hours. PNGase F will not remove oligosaccharides containing Alpha-(1,3)-linked core fucose commonly found on plant glycoproteins; for this purpose, use peptide N-glycosidase A. There are a number of alternative enzymes which can be used to remove N-glycans, most especially the Endo F family of enzymes and Endo H. These enzymes cleave between the two N-acetylglucosamine residues in the core of the oligosaccharide, generating a truncated sugar molecule with one N-acetylglucosamine residue remaining on the asparagine. This leaves a charged sugar which can assist in keeping proteins in solution that precipitate after deglycosylation with PNGase F which removes the oligosaccharide intact. Endo F1cleaves high mannose and some hybrid type N-glycans. Endo F2will removes biantennary and high mannose (at a 40X reduced rate). Endo F3releases of triantennarry and fucosylated biantennary N-glycans. Endo Hremoves hybrid or high mannose glycans.