Unless genetically engineered, plant N-glycans can be oligomannose, complex, hybrid and paucimannose with the N-glycans often modified at the core b-mannose with a b1-2 xylose residue. Additionally, the GlcNAc core of the N-glycan can be modified by an a1-3 fucose (Fig. 1). This core modification:
- Is known to be allergenic in humans
- Makes N-glycans resistant to PNGase F cleavage
- Can be cleaved by PNGase A and Endo D
Generally, insect N-glycans tend to be either high-mannose or paucimannose structures and unless genetically engineered the N-glycans also can be modified at the GlcNAc core by an a1-3 fucose (Fig. 1).
- What is the difference between PNGase F and PNGase A?
- Can PNGase A be used under non-denaturing (native) conditions?
- Which high mannose structures can PNGase A cleave?
- Can PNGase A cleave large, complex oligosaccharides?
- What happens to the asparagine after PNGase A removes the sugar?
- What is a good PNGase A substrate?
- Is PNGase A compatible with downstream analysis such as HPLC and Mass Spectrometry?
Learn about the core sequences and common modifications of N-linked and O-linked glycans in this video. Analysis of these glycans can be accomplished with the use of deglycosylation enzymes, which can provide complete sugar removal with no protein degradation.
Behind the Paper: An engineered Fbs1 carbohydrate binding protein for selective capture of N-glycans and N-glycopeptides
Minyong and Jim summarize their recent Nature Communications publication describing selective capture of N-glycans and N-glycopeptides by an engineered high affinity Fbs1 carbohydrate binding protein.