Question

According to the textbook: “lectin and glycan arrays provide a platform to screen large number of samples for specific binding interactions using fluorescently labeled molecules. Two basic types of arrays have been developed for screening purposes: (1) protein arrays containing covalently attached lectin proteins or antibodies for the detection of labeled glycoproteins in experimental samples; and (2) glycan arrays containing covalently attached glycoproteins with intact glycan groups (or chemically synthesized glycan groups) for the detection of labeled lectin proteins or antibodies in experimental samples. Pick one type of array. Explain one advantage and one disadvantage to this type of glycan analysis. Find a method that has been developed to overcome the disadvantage that you listed and briefly explain how it works.

Answer 1

Lenctin and Glycan:

Lectins are carbohydrate-binding proteins that are highly specific for sugar groups of other. Glycan arrays, are composed of various oligosaccharides or polysaccharides immobilized on a solid support.

lectins (carbohydrate binding proteins other than antibodies) and glycan-binding antibodies are used  as research tools, diagnostics, and therapeutic agents to detect and target glycans.

The common application of glycan array technology is the analysis of binding specificity of lectins and antibodies.Binding has primarily been detected using fluorescently labeled samples or secondary reagents, however, other methods of detection like mass spectroscopy and surface plasma resonance have been used. When interpreting binding profiles, the assay conditions and array platform should be considered.At high concentrations a lectin may bind many different glycan structures while at lower concentrations it may only bind a small carbohydrates.

Advantage:

Their advantage is that they are easier to immobilize by hydrophobic forces on the chemical surface.

Disadvantage:

The main disadvantages is that high ligand concentrations are required with quixotic when working with complex oligosaccharides.

Glycoproteins:

Glycoproteins are proteins which contain oligosaccharide chains glycans covalently attached to amino acid. Glycoproteins are important integral membrane proteins, they play a role in cell–cell interactions.