Project description:Owing to their ability to secrete antimicrobials and benefit human health, lactic acid bacteria (LAB) cultures are an attractive nontoxic alternative to antibiotics for preserving food and combating pathogenic infections. Given that this strategy has several limitations, including strain-dependent antimicrobial effectiveness, reduced efficacy against multidrug-resistant strains, and difficulties in large-scale production without bacterial contamination, current research focuses on identifying and utilizing endolysins (enzymes that degrade bacterial cell walls) produced by novel or engineered LAB cultures to inhibit pathogen growth. The challenges faced by this approach (e.g., bactericidal activity lower than that of antibiotics, susceptibility to degradation by proteases, and high purification and quality control costs) can be overcome using engineered LAB-derived extracellular vesicles (LEVs) displaying pathogen-specific endolysins on their surface to directly recognize and eliminate target pathogens. Given that no LEV surface-displayed proteins (SDPs) have been characterized to date, this study identifies and characterizes a LEV SDP (LP-SDP3) from Lacticaseibacillus paracasei using proteomic analysis, heterologous expression of candidate SDPs, biochemical analysis, and SpyTag–SpyCatcher reactions. LP-SDP3 homologs are found in Escherichia coli and other LAB strains, exhibiting the same function in E. coli and Lactococcus lactis. Endolysin (PlyF307SQ-8C)-displaying LEVs derived from L. paracasei selectively kill Staphylococcus aureus, exhibiting an activity comparable with that of purified PlyF307SQ-8C. This study is the first to identify a universal extracellular vesicle SDP for E. coli and LAB strains, demonstrating its potential as a platform for developing endolysin–extracellular vesicle antibacterials without the need for labor-intensive and costly endolysin preparation.

2025-07-21 | PXD059432 | Pride

Lacticaseibacillus paracasei strain:MRD4401 | isolate:female

Project description:Lacticaseibacillus paracasei strain:MRD4401 | isolate:female Genome sequencing

| PRJNA1183613 | ENA

Lacticaseibacillus paracasei strain:Prokaryote | isolate:Prokaryote

Project description:Lacticaseibacillus paracasei strain:Prokaryote | isolate:Prokaryote Genome sequencing

| PRJNA756773 | ENA

Lacticaseibacillus paracasei strain:MRD1299 | isolate:female

Project description:Lacticaseibacillus paracasei strain:MRD1299 | isolate:female Genome sequencing

| PRJNA1183588 | ENA

Lacticaseibacillus paracasei subsp. paracasei strain:2LB

Project description:Lacticaseibacillus paracasei subsp. paracasei strain:2LB