Single Amino Acid Changes Impact the Ability of Drosophila melanogaster Cecropins to Inhibit Growth of Providencia Pathogens

ACS Omega, Год журнала: 2025, Номер 10(6), С. 5403 - 5414

Опубликована: Фев. 5, 2025

As antibiotic-resistant bacteria spread worldwide, the need to develop novel antimicrobial agents is urgent. One rich source of potential antimicrobials insect immune system, as insects produce a wide range peptides (AMPs) with diverse sequences and structures. Insects also encounter many bacterial pathogens, some which are closely related pathogens clinical relevance. However, despite interest in AMPs therapeutics, relationships between amino acid sequence, biophysical properties, activity, specificity still not generalizable. To improve our understanding these relationships, we assessed how single changes cecropin produced by fruit fly, Drosophila melanogaster, impact both their structure ability inhibit growth Providencia species isolated from wild-caught D. melanogaster. These particular they have virulence flies, work vivo suggests that differences could be partially attributable differential susceptibility AMPs. melanogaster cecropins 40 acids long but vary at only 5 residues largely conservative changes. We found inhibitory concentrations up 8-fold against species. Our investigation focused on position due importance flexible "hinge" function. altering identity this alone greatly impacted changing 16-fold. Generally, less virulent more susceptible vitro. observed kinetics permeabilization killing species, suggesting peptide-membrane interactions were differently affected genus may membrane composition.

Язык: Английский

A Hypothetical Protein Fragment from Large Yellow Croaker (Larimichthys crocea) Demonstrates Significant Activity Against Both Bacterial and Parasite

Fishes, Год журнала: 2025, Номер 10(3), С. 109 - 109

Опубликована: Март 4, 2025

Antimicrobial peptides (AMPs) are biocompatible and biodegradable, making them an attractive alternative to traditional antimicrobial agents chemical preservatives. Here, a novel α-helix amphiphilic anionic AMP Lc149 was screened from large yellow croaker (Larimichthys crocea) using Bacillus subtilis expression system. is hypothesized protein fragment not annotated in the genome of croaker. Both extracellular recombinant (rLc149) exhibited significant killing effects against Gram-negative Escherichia coli Vibrio harveyi. Scanning transmission electron microscopy revealed that rLc149 had ability disrupt bacterial cell membranes, causing irregular morphology, severe membrane damage, cytoplasm agglutination, intracellular content leakage. Confocal laser scanning flow cytometry further confirmed destruction mortality rates over 80%. Gel retardation assays SDS-PAGE electrophoresis showed unable bind DNA, but did reduce contents. Additionally, maintained antibacterial activity E. V. harveyi upon exposure temperatures 25–100 °C, UV radiation time 0–60 min, pH levels 3–12, different proteases. Biosafety low hemolytic toxicity erythrocytes croaker, rabbit, shrimp, cytotoxicity kidney cells HEK 293T cells. More deeply, also possessed parasites. Therefore, can be considered antiparasitic drug fisheries.

Язык: Английский

Esc peptides and derivatives potentiate the activity of CFTR with gating defects and display antipseudomonal activity in cystic fibrosis-like lung disease

Cellular and Molecular Life Sciences, Год журнала: 2025, Номер 82(1)

Опубликована: Март 18, 2025

Abstract Cystic fibrosis (CF) is a rare disease caused by mutations in the gene encoding CF transmembrane conductance regulator (CFTR), chloride channel with an important role airways. Despite clinical efficacy of present modulators restoring activity defective CFTR, there are patients who show persistent pulmonary infections, mainly due to Pseudomonas aeruginosa . Recently, we reported unprecedented property antimicrobial peptides i.e. Esc peptides, which consists their ability act as potentiators CFTR carrying most common mutation (the loss phenylalanine 508) affecting protein folding, trafficking and gating. In this work, electrophysiology experiments computational studies, capability these de-novo designed analogs was demonstrated recover function other mutated forms severely affect gating (G551D G1349D). This presumably direct interaction nucleotide binding domains (NBDs) followed novel local phenomenon consisting distancing residues located at cytosolic side NBDs interface, thus stabilizing open conformation pore its end. The promising for dual potentiator activities were also shown display antipseudomonal conditions mimicking ion transport mucus obstruction, higher than clinically used colistin. These studies should assist development drugs lung pathology CF, large spectrum antibiotic activities.

Язык: Английский