Activity of Antimicrobial Peptide Aggregates Decreases with Increased Cell Membrane Embedding Free Energy Cost
journal contributionposted on 2018-04-11, 00:00 authored by Rongfeng Zou, Xiaomin Zhu, Yaoquan Tu, Junchen Wu, Markita P. Landry
Antimicrobial peptides (AMPs) are a promising alternative to antibiotics for mitigating bacterial infections, in light of increasing bacterial resistance to antibiotics. However, predicting, understanding, and controlling the antibacterial activity of AMPs remain a significant challenge. While peptide intramolecular interactions are known to modulate AMP antimicrobial activity, peptide intermolecular interactions remain elusive in their impact on peptide bioactivity. Herein, we test the relationship between AMP intermolecular interactions and antibacterial efficacy by controlling AMP intermolecular hydrophobic and hydrogen bonding interactions. Molecular dynamics simulations and Gibbs free energy calculations in concert with experimental assays show that increasing intermolecular interactions via interpeptide aggregation increases the energy cost for the peptide to embed into the bacterial cell membrane, which in turn decreases the AMP antibacterial activity. Our findings provide a route for predicting and controlling the antibacterial activity of AMPs against Gram-negative bacteria via reductions of intermolecular AMP interactions.
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energy costGram-negative bacteriapeptide intramolecular interactionscell membraneenergy calculationsCell Membrane Embedding Free Energy Cost Antimicrobial peptidesAntimicrobial Peptide Aggregates DecreasesAMP interactionsMolecular dynamics simulationsassays showAMP antimicrobial activitypeptide bioactivityinterpeptide aggregation increases