Structure-Based Adaptation of a SARS-CoV-2 Neutralizing Peptide to New Virus Variants

Area of Science:

• Virology
• Structural Biology
• Drug Discovery

Background:

• Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants like Omicron evade existing neutralizing antibodies.
• The peptide LW25.13 initially neutralized SARS-CoV-2 by targeting the spike protein's receptor-binding domain (RBD) and blocking ACE2 interaction.
• Limitations in LW25.13's neutralization breadth against emerging variants necessitated structural and bioinformatic optimization.

Purpose of the Study:

• To engineer the SARS-CoV-2 neutralizing peptide LW25.13 for broader variant neutralization.
• To maintain the peptide's efficacy against original SARS-CoV-2 strains and its stability.
• To explore the peptide as an adaptable scaffold for developing antivirals against future coronavirus variants.

Main Methods:

• Structural and bioinformatic analysis guided systematic variations of peptide positions.
• Peptide variants were synthesized and tested for neutralization capacity against multiple SARS-CoV-2 variants.
• Proteolytic stability and secondary structure (alpha-helical conformation) were assessed.

Main Results:

• Engineered peptides demonstrated neutralization of SARS-CoV-2 Beta and Omicron variants at low nanomolar concentrations.
• The enhanced peptides retained potent neutralizing activity against wild-type, Alpha, and Delta SARS-CoV-2 strains.
• Key properties such as proteolytic stability and alpha-helical conformation were preserved in the modified peptides.

Conclusions:

• Systematic peptide modification successfully broadened neutralization against SARS-CoV-2 variants.
• The optimized peptide scaffold shows promise for developing therapeutics against emerging and future coronavirus variants.
• This approach highlights the potential of peptide-based antivirals in combating rapidly evolving viruses.