This paper reviews how tiny proteins like LL‑37 can mess with bacteria’s “talking” system (quorum‑sensing) so they become less harmful without killing them, which might help fight antibiotic resistance. It explains the science, shows that natural and engineered peptides can block bacterial signals, and notes the big hurdles like making the peptides stable and getting them into the body.

The rise of antimicrobial resistance (AMR) has outpaced the development of new antibiotics, necessitating alternative therapeutic strategies that do not rely on conventional bactericidal approaches. Quorum-sensing (QS), a bacterial communication system that regulates virulence, biofilm formation and genetic competence, has emerged as a promising non-lethal target. Peptide-based quorum-sensing inhibitors (QSIs) including antimicrobial peptides (AMPs), cyclic dipeptides, and synthetic analogs are gaining recognition for their ability to disrupt QS pathways and attenuate pathogenicity without promoting resistance. This review summarizes recent advancements in peptide-mediated QS interference, covering mechanistic insights, molecular design strategies, and application domains. Natural AMPs such as LL-37 and GH12 modulate QS by altering gene expression or blocking receptor function, while marine-derived cyclic dipeptides act as competitive inhibitors of QS receptors like LasR and CviR. Engineered peptides and peptide-nanocomposite systems have demonstrated improved stability and target specificity, particularly against multidrug-resistant pathogens. Applications span wound healing, prevention of dental biofilms, and prevention of infectious diseases development. However, challenges remain, including peptide instability, low bioavailability, off-target effects, and potential resistance development. Peptide-based QSIs represent a paradigm shift in antimicrobial therapy by disabling bacterial virulence without directly killing cells. Advances in peptide engineering, delivery systems, and synthetic biology are accelerating their clinical and environmental translation. With continued innovation and adapted regulatory frameworks, peptide-based QS inhibition may become a cornerstone of next-generation anti-virulence therapeutics.