Bacterial Membrane Vesicles: Biogenesis, Functions, and Emerging Biotechnological Applications

Bacterial membrane vesicles (BMVs) are non-replicative, bilayered nanostructures secreted by both Gram-negative and Gram-positive bacteria. Rather than being passive byproducts of cell envelope turnover, BMVs are increasingly recognized as regulated particles that selectively package proteins, lipids, nucleic acids, and other bioactive molecules. Through these cargos, BMVs mediate a wide range of biological processes, including bacterial stress adaption, intercellular communication, virulence delivery, and host immune modulation. In this review, we integrate recent advancements in understanding the molecular mechanisms underlying BMV biogenesis and composition and discuss how their heterogeneity contributes to their functional diversity. Beyond their biological roles, we critically examine the translational potential of BMVs in vaccine development, targeted drug delivery, cancer therapy, diagnostic tools, and biotechnological applications. However, significant challenges related to their safety, efficacy, and large-scale production must be addressed to realize their full clinical potential. We review recent progress and ongoing obstacles in the use of BMVs across various biomedical applications and propose strategies for their clinical translation.