Relating Molecular Dynamics Simulations to Functional Activity for Gly-Rich Membranolytic Helical Kiadin Peptides

Area of Science:

• Antimicrobial Peptides
• Computational Chemistry
• Biophysics

Background:

• Kiadins are novel peptides designed computationally, mimicking the diPGLa-H sequence.
• Glycine substitutions in kiadins significantly alter their properties.

Purpose of the Study:

• To investigate the impact of glycine substitutions on kiadin activity, selectivity, and cytotoxicity.
• To correlate molecular dynamics simulations with experimental data on peptide-membrane interactions.

Main Methods:

• In silico design of kiadins with varying glycine content.
• Molecular dynamics simulations to study peptide structure and membrane interactions.
• Experimental determination of kiadin structure, liposome interactions, antibacterial activity, and cytotoxicity.

Main Results:

• Glycine substitutions led to diverse antibacterial activity against Gram-negative and Gram-positive bacteria.
• Peptide structure, conformational flexibility, and membrane interactions varied with glycine placement.
• Experimental data aligned with simulation findings, showing varied antibacterial potency and host cell toxicity.

Conclusions:

• The number and position of glycine residues are critical determinants of kiadin antibacterial efficacy and host cell toxicity.
• Multiscale approaches are essential for understanding the complex relationship between peptide sequence, structure, and function.
• Further research is needed to fully elucidate the mechanisms underlying glycine's influence on peptide performance.