Temperature Effects on the Structural Stability of EF4K Peptide Membranes: Insights into Mono- and Multilayer Architectures

TL;DR

This study explores how temperature affects the stability of EF4K peptide membranes, showing that multilayer structures are more resilient than monolayers.

Contribution

The paper reveals how multilayer EF4K assemblies maintain stability under thermal stress through supramolecular reinforcement.

Findings

Hydrogen bond lifetimes in EF4K membranes decrease by nearly 79% with increasing temperature.

Multilayer configurations reinforce peptide–peptide interactions and stabilize electrostatic contributions.

Confined water in multilayers shows longer hydrogen bond lifetimes compared to monolayers at higher temperatures.

Abstract

Peptide nanostructures are versatile supramolecular systems
with
potential applications in biomaterials and nanotechnology, where stability
emerges from the cooperative action of noncovalent interactions. In
this study, we investigated the bola-amphiphilic peptide EF4K assembled into nanomembranes, focusing on the combined effects
of temperature and multilayer organization. Molecular dynamics simulations
were conducted at 250, 270, 300, 320, and 350 K in monolayer and multilayer
configurations, allowing direct evaluation of peptide–peptide
and peptide–solvent interactions. The results demonstrate that
while the number of hydrogen bonds increases with temperature, their
lifetimes decrease markedly, with reductions of nearly 79%. Peptide–solvent
interactions weaken significantly, with losses of up to 90%, whereas
multilayer assemblies partially compensate this destabilization by
reinforcing peptide–peptide hydrogen bonds and van der Waals
contacts. Electrostatic contributions between peptides remain stable
and even strengthen in multilayers, indicating supramolecular reinforcement
upon stacking. Confined water within multilayers exhibits longer hydrogen
bond lifetimes despite a lower number of contacts, contrasting with
the destabilization of hydration shells observed in monolayers at
higher temperatures. These findings reveal that EF4K membranes
undergo a redistribution of stabilizing forces under thermal stress,
with multilayers achieving enhanced internal cohesion, thereby highlighting
their potential as robust peptide-based nanomaterials.

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