polybia-mastoparan I

**Polybia-mastoparan I** is a cationic, amphipathic, α-helical peptide composed of 14 amino acids (sequence: IDWKKLLDAAKQIL)[5], originally isolated from the venom of the social wasp Polybia paulista[5][2][7]. It exhibits strong **antimicrobial** and **anticancer** activity, especially against Gram-positive and Gram-negative bacteria and various cancer cell lines, including bladder cancer[5][7]. Its mechanism centers on selective interaction with cell membranes: it binds to anionic phospholipids (abundant in microbial and cancer cells), inserts to destabilize and lyse the membranes, resulting in cell death[5][7]. The peptide shows preferential toxicity towards cancer and bacterial cells while exhibiting lower cytotoxicity to non-tumorigenic mammalian cells at relevant doses[5]. This selectivity makes it a promising candidate “antibiotic peptide” or “antitumor peptide,” and the peptide has also demonstrated utility as a template scaffold for future drug design[5][7]. Delivery strategies, such as nanoparticle encapsulation, have been explored to increase antitumor efficacy and reduce off-target toxicity[5].

Other names

Polybia–mastoparan IPolybia-MP-IMPI