Understanding β-strand mediated protein-protein interactions: tuning binding behaviour of intrinsically disordered...

Area of Science:

• Chemical Biology
• Structural Biology
• Biochemistry

Background:

• Protein-protein interactions (PPIs) are crucial biological processes.
• Many PPIs involve intrinsically disordered peptide sequences.
• Understanding and modulating PPIs is a key challenge in chemical biology.

Purpose of the Study:

• To investigate the effect of backbone N-methylation on peptide conformation and protein binding.
• To explore N-methylation as a tool for modulating peptide recognition in PPIs.
• To utilize the SUMO-SIM interaction as a model system.

Main Methods:

• Peptide synthesis with backbone N-methylation.
• Relaxation-based Nuclear Magnetic Resonance (NMR) experiments.
• Computational analysis of binding thermodynamics.

Main Results:

• Backbone N-methylation restricts peptide conformational flexibility.
• N-methylated peptides exhibit enhanced binding affinity and faster target recognition.
• Thermodynamic analysis reveals increased unbound state energy and reduced entropic penalties.

Conclusions:

• Backbone N-methylation is a valuable strategy to pre-dispose peptides for protein recognition.
• This modification enhances binding affinity by altering the unbound state and entropic contributions.
• N-methylation offers a novel approach within the peptidomimetic toolbox for studying beta-strand mediated interactions.