Exploration of mucin-protein interactions using liquid glycan array.

Area of Science:

• Biotechnology
• Molecular Biology
• Glycobiology

Background:

• M13 phage can display molecules via DNA-barcoding, enabling a 1:1 link between displayed molecule and DNA sequence.
• This DNA-encoded display allows for controlled multivalency, where DNA barcodes correlate with displayed density.

Purpose of the Study:

• To develop a DNA-encoded multivalent system for glycan recognition profiling.
• To investigate the binding properties of mucin-binding proteins using this novel system.

Main Methods:

• Chemical conjugation of glycans to M13 virions with introduced DNA barcodes to create DNA-barcoded glycophages.
• Utilizing a collection of these DNA-barcoded multivalent glycophages, termed Liquid Glycan Array (LiGA).
• Testing the binding of mucinase StcE (StcE^E447D) to various ultra-dense displays of D-galactose and control sugars.

Main Results:

• LiGA successfully measured the glycan-recognition profile of mucin-binding proteins.
• An ultra-dense display of D-galactose on M13 phages demonstrated binding to StcE^E447D, mimicking mucin.
• Specificity was confirmed as StcE^E447D did not bind to L-galactose, D-glucose, or D-mannose displays.

Conclusions:

• DNA-encoded multivalency using M13 phages (LiGA) is an effective tool for studying glycan-protein interactions.
• Ultra-dense displays of specific glycans can present unique binding characteristics, as exemplified by D-galactose binding to StcE^E447D.
• This approach offers a novel method for characterizing the specific recognition profiles of proteins like mucin-binding enzymes.