Glycoprofiling is used by the biopharmaceutical industry to analyze the glycans found on glycoproteins being developed as therapeutics. It is also a key assay for the lot release characterization of manufactured glycoproteins both before and after approval.
The process can be broken down as follows:
Release of glycans from glycoprotein
capture and cleanup of released glycans
labeling of released glycans
purification and cleanup of labeled glycans
analysis of glycan using MS, HPLC, or CE to produce the glycan profile
QAbio Glycan Release
Typically, PNGase F is used to release N-linked glycans. The enzyme works quickly and effectively, cleaving the glycans in native conditions in most cases. The Endo F family of enzymes are also commonly used for glycan release. These three enzymes vary in specificity to the multi-antennary structures found on N-linked glycans. They also differ from PNGase F in that they leave the penultimate glycan, a charged N-acetyl-glucosamine, attached to the protein. Both PNGase F and the Endo F family of enzymes leave the glycan with a free reducing terminii suitable for fluorescent labelling.
For O-linked glycan release, the Ludger Liberate Orela Kit allows the release of glycans that have free reducing terminii suitable for fluorescent labelling. The kit is straightforward and contains a simple method with no special handling techniques as required by the alternative method, hydrazinolysis.