Introduction, History, and Discovery of Bacterial Membrane Vesicles

Abstract

The production of extracellular vesicles is a conserved process that is common to all living cells. Both Gram-negative and Gram-positive bacteria produce extracellular vesicles, known as outer membrane vesicles (OMVs) and membrane vesicles (MVs), respectively. Once disregarded as artifacts of bacterial growth, research over the last 50 years has shown that OMVs contribute to numerous bacterial functions. It is now understood that OMVs are purposely secreted by Gram-negative bacteria to aid in bacterial communication and pathogenesis. The OMV field has focused on understanding the mechanisms of OMV biogenesis, the content of OMVs and how OMVs interact with the host immune system and their environment. While there is a wealth of knowledge regarding OMVs, it was only in the last decade that Gram-positive bacteria were found to release MVs. Due to the late discovery of MVs there is little known about MVs in comparison to our knowledge regarding OMVs. However, there is emerging evidence that MVs contain bacterial cargo and may aid in bacterial functions. Research in the field of bacterial vesicles has expanded rapidly within the past decade and continues to be a growing field of interest. Future work aims to manipulate bacterial membrane vesicles as novel therapeutics and nanoparticle technology.