What is a glycan binding protein?

Glycan-binding proteins are proteins which recognise and bind specific sequences of glycans and therefore facilitate cellular processes based on the glycomic profile.

How are glycans synthesized?

Synthesis of Glycans Using Glycosidases They are separated into two categories: endoglycosidases, which cleave internal glycosidic bonds of glycans, and exoglycosidases, which cleave of the nonreducing terminal sugar of a glycan.

What are glycan structures?

Glycans are chain-like structures that are composed of single sugar molecules (monosaccharides) linked together by chemical bonds.

Where are glycans synthesized in the cell?

The Golgi complex is the main generator of glycan diversity in eukaryotic cells. It houses a large assortment of glycosyltransferases, glycosidases and other enzymes needed for oligosaccharide synthesis and modification.

What does O-linked glycosylation do?

O-linked glycosylation is the attachment of a sugar molecule to the oxygen atom of serine (Ser) or threonine (Thr) residues in a protein. O-glycosylation is a post-translational modification that occurs after the protein has been synthesised.

Where are O linked glycans found?

O-glycosylation is a post-translational modification that occurs after the protein has been synthesised. In eukaryotes, it occurs in the endoplasmic reticulum, Golgi apparatus and occasionally in the cytoplasm; in prokaryotes, it occurs in the cytoplasm.

Why is glycan analysis important?

The glycan moieties attached to the proteins can directly affect protein stability, bioactivity, and immunogenicity. Therefore, glycan variants of a glycoprotein product must be adequately analyzed and controlled to ensure product quality.

What is N and O-linked glycosylation?

N-linked glycosylation requires participation of a special lipid called dolichol phosphate. O-linked glycans attached to the hydroxyl oxygen of serine, threonine, tyrosine, hydroxylysine, or hydroxyproline side-chains, or to oxygens on lipids such as ceramide.

Why is O-linked glycosylation important?

As stated previously, a specific type of O-linked glycosylation, O-GlcNAcylation, is an important posttranslational protein modification regulating diverse cellular processes, such as gene expression, protein stability and cell signaling dynamics.

Where does O-linked glycosylation begin?

O-linked glycoproteins begin their glycosylation with the action of the Golgi-specific enzyme, GalNAc transferase, which attaches an N-acetylgalactosamine to the hydroxyl group of a serine or threonine.