Top Picks,Nisin, a small antimicrobial peptide

Nisin, a well-established antimicrobial peptide commonly utilized as a food preservative, is increasingly recognized for its remarkable capacity to act as a cell penetrating peptide. This unique characteristic, stemming from its phospholipidic composition, facilitates its easy penetration of targeted cells without the need for specific cell-surface receptors. This inherent ability of nisin to traverse cellular membranes is opening doors for novel therapeutic and diagnostic applications beyond its traditional role in food safety.

Research indicates that nisin is a polycyclic antibacterial peptide composed of 34 amino acid residues, produced by the bacterium Lactose lactis during fermentation. Its structure, characterized by an overall positive charge and containing unsaturated amino acids and lanthionine residues due to posttranslational modifications, contributes to its interaction with the lipid layer of bacterial cell membranes, leading to disruption and pore formation. This mechanism is particularly effective against vegetative forms of spore-forming bacteria and allows nisin to rapidly penetrate biofilms.

The cell penetrating nature of nisin is a key factor driving its exploration in biomedical fields. Emerging research highlights its capacity as a cell penetrating peptide, demonstrating its potential in various therapeutic strategies. For instance, studies have shown that nisin can induce selective toxicity and apoptotic cell death in cultured melanoma cells. Furthermore, nisin has been suggested as a novel potential therapeutic approach to treat cancer with no reported toxicity in humans.

The anticancer potential of nisin is a significant area of investigation. Nisin ZP, a specific variant, exhibits greater antitumor effects than lower content nisin, showing promise as a novel therapeutic for Head and Neck Squamous Cell Carcinoma (HNSCC). Nisin ZP has also demonstrated anticancer activity in melanoma, hepatic, colon, and blood cancer cells in vitro. Moreover, Nisin ZP, an antimicrobial peptide, has been shown to induce cell death and inhibit Non-Small Cell Lung Cancer (NSCLC) progression in vitro. These findings underscore the synergistic antitumor effect of nisin treatment, enhancing tumor cell apoptosis.

Beyond its anticancer applications, nisin possesses antibacterial and anti-inflammatory activity. In vitro studies have shown that nisin can inhibit HNSCC cell ballooning. The ability of nisin to penetrate cells is further supported by research demonstrating its effectiveness against *Staphylococcus aureus* biofilms, where its penetration and efficacy were monitored in real-time.

The exploration of nisin as a cell penetrating peptide is an active and evolving field. Its phospholipidic composition is integral to its ability to enter cells easily. While its primary role has been in food safety, the emerging research highlights its capacity as a cell penetrating peptide, opening doors for novel applications in medicine and beyond. The peptide nisin is a fascinating molecule with a dual identity: a reliable food preservative and a potent therapeutic agent with the remarkable ability to traverse cellular barriers. This understanding of nisin as a cell penetrating agent is crucial for unlocking its full potential.