Zinc-binding peptides inactivate Pseudomonas aeruginosa via disrupting membrane and interfering with quorum-sensing

Pseudomonas aeruginosa (P. aeruginosa), recognized for its biofilm production and secretion of virulence factors, posing a severe threat in areas such as clinical infections, food contamination, and marine biofouling. To address this, a new type of zinc-chelating peptide (CSSP-Zn) was prepared from crimson sapper scales peptides (CSSP) and goslarite, and its antibacterial and anti-quorum-sensing activities toward P. aeruginosa PAO1 were exploited. Results indicated that CSSP-Zn induced planktonic strain PAO1 membrane injury via inhibiting expression levels of cell integrity genes, targeting microbial-specific membrane constituents, disrupting proton motive force, and causing metabolic disturbances. Meanwhile, CSSP-Zn decreased virulence factors pyocyanin, protease, and rhamnolipid secretion, while considerably inhibiting quorum sensing-related genes (las, pqs, and rhl) expression and decreasing bacterial abundance and pathogenicity in fish models. Moreover, CSSP-Zn not only effectively hindered biofilm formation but also disassembled preformed ones, thus disrupting biofilm topology. Taken together, utilizing food byproducts to obtain CSSP-Zn could help recycle food resources, and provide insight into controlling planktonic and biofilm strain PAO1 contamination.