Reversible Covalent Reactions of Aldehydes and Salicylaldehydes Using a Lysine-Model Substrate

Area of Science:

• Chemical Biology
• Medicinal Chemistry
• Organic Chemistry

Background:

• Lysine residues are crucial in biological processes and protein function.
• Covalent modification of lysine offers potential in drug development.
• Aldehyde-based chemistries are explored for targeting lysine residues.

Purpose of the Study:

• To investigate the reactivity profiles of aldehydes and salicylaldehydes for lysine modification.
• To determine the binding affinities and kinetic profiles of various aldehyde-based warheads.
• To understand how warhead structure influences covalent binding to lysine.

Main Methods:

• Utilized a lysine-surrogate model system.
• Monitored reactions of aldehydes and salicylaldehydes over time.
• Determined dissociation constants (KD) and analyzed kinetic profiles.

Main Results:

• Observed significant differences in binding affinity based on warhead substitution.
• Aldehydes reacted rapidly, reaching equilibrium quickly.
• Salicylaldehydes showed slower reaction kinetics, requiring hours to reach equilibrium.

Conclusions:

• Warhead structure critically influences the kinetics of covalent modification of lysine residues.
• These findings provide insights for developing novel chemical modifications for drug discovery.
• Reversible covalent targeting of lysines can be achieved with tailored reactive warheads.