Tachyplesin II is a broad-spectrum cationic antimicrobial peptide. It exhibits significant inhibitory effects on Gram-positive bacteria, Gram-negative bacteria, and certain fungi. By engaging its positive charge, Tachyplesin II binds to bacterial membrane lipopolysaccharides, disrupting membrane integrity and causing leakage of cellular contents. Additionally, Tachyplesin II binds to DNA grooves to inhibit microbial replication and can also suppress HIV-1 replication and liver cancer cell proliferation.