Role of Lipid Composition in the Antimicrobial Peptide Double Cooperative Effect

Abstract

The antimicrobial peptide double cooperative effect, where the mixture of two major antimicrobial peptides LL-37 and HNP1 kills bacteria more efficiently while minimizing the host damage by suppressing mammalian cell membrane lysis, has garnered attention due to its potential applications toward efficient and safe antibiotics. However, its mechanism is completely unknown. In this work, we report that the double cooperative effect can be partially recapitulated in synthetic lipid systems just by varying the lipid composition between eukaryotic and Escherichia coli membranes. Although real cell membranes are so much more complex than just lipids, including, e.g., membrane proteins and polysaccharides, our data implicates that one of the main driving forces of the double cooperative effect is a simple lipid−peptide interaction.

Mechanical Properties of Polydiacetylene Multilayers Studied by AFM Force Spectroscopy

“…The repeating unit ( d ∼ 3.1 nm) corresponds to the height of a double layer at around 52° tilt angle relative to the substrate, supposing that the molecular length of TRCDA is L = 2.5 nm, which is roughly consistent with the reported values . Note that the length of POPC is also around L ∼ 2.3 nm; − thus, its potential mixture inside the TRCDA matrix does not contradict with this interpretation. Therefore, the monolayer thickness d is roughly estimated as 3.1 ÷ 2 = 1.5 nm.…”

DEFA1A3DNA gene-dosage regulates the kidney innate immune response during upper urinary tract infection

“…In addition, α-Defensin 1-3 at mucosal surfaces can be expressed in conjunction with other AMPs and innate immune 1 components against microbes (31). Studies to further expand the understanding of synergistic effects could further provide translational utility against drug-resistant uropathogens (32,33,34,35). The objective of this study was to evaluate the mechanistic role of α-Defensin 1-3/DEFA1A3 protection in the kidney against uropathogenic Escherichia coli (UPEC) infection burden and inflammation.…”