Microbial vesicles: From ecosystem to diseases

The production of outer membrane vesicles (OMVs) is conserved in eukaryotes and prokaryotes. OMVs are double-layered structures with contents from outer membrane, periplasmic space, and even cytosol. Some of them have been shown to contain nucleic acids as well, which explains the specialized system for the packaging of these vesicles. OMVs mediate essential processes such as transport of nutrients, antigens, and virulence factors, etc., which help the microorganisms in communication as well as in killing of other microbial cells. The biogenesis of OMVs differs in bacteria and archaea. The archaeal OMV biogenesis is similar to eukaryotes involving ESCRT machinery, while in gram-negative bacteria, it occurs either due to broken OM-PG interaction or due to increased periplasmic pressure. OMVs containing antigens have been recently explored for use as vaccine which provides another dimension for its applications.