Lung SPLUNC1 Peptide Derivatives in the Lipid Membrane Headgroup Kill Gram-Negative Planktonic and Biofilm Bacteria.

SPLUNC1 (short palate lung and nasal epithelial clone 1) is a multifunctional host defense protein found in human respiratory tract with antimicrobial properties. In this work, we compare the biological activities of four SPLUNC1 antimicrobial peptide (AMP) derivatives using paired clinical isolates of the Gram-negative (G(-)) bacteria , obtained from 11 patients with/without colistin resistance. Secondary structural studies were carried out to study interactions between the AMPs and lipid model membranes (LMMs) utilizing circular dichroism (CD).

Rational Framework for the Design of Trp- and Arg-Rich Peptide Antibiotics Against Multidrug-Resistant Bacteria.

The threat of antibiotic resistance warrants the discovery of agents with novel antimicrobial mechanisms. Antimicrobial peptides (AMPs) directly disrupting bacterial membranes may overcome resistance to traditional antibiotics. AMP development for clinical use has been mostly limited to topical application to date.

Location of the Hydrophobic Surfactant Proteins, SP-B and SP-C, in Fluid-Phase Bilayers.

The hydrophobic surfactant proteins, SP-B and SP-C, promote rapid adsorption by the surfactant lipids to the surface of the liquid that lines the alveolar air sacks of the lungs. To gain insights into the mechanisms of their function, we used X-ray diffuse scattering (XDS) and molecular dynamics (MD) simulations to determine the location of SP-B and SP-C within phospholipid bilayers. Initial samples contained the surfactant lipids from extracted calf surfactant with increasing doses of the proteins.