Listeriolysin O Fusion Protein

Listeriolysin O (LLO) fusion proteins are engineered chimeric molecules that combine the pore-forming, endosomolytic properties of LLO—a toxin produced by *Listeria monocytogenes*—with other functional domains, such as DNA-binding or antigenic sequences. These fusion proteins are designed to enhance cellular delivery and immunogenicity in various biomedical applications, including nonviral gene delivery and vaccine development. Upon internalization into cells via endocytosis, the acidic environment within endosomes activates the pore-forming activity of LLO, enabling the release of cargo into the cytoplasm.

Acid-triggered pore formation in endosomal membranes, leading to cytosolic release of fused cargo (DNA, antigens).