Extracellular vesicles: An emerging platform in gram-positive bacteria

Microb Cell. 2020 Oct 5;7(12):312-322. doi: 10.15698/mic2020.12.737.

Abstract

Extracellular vesicles (EV), also known as membrane vesicles, are produced as an end product of secretion by both pathogenic and non-pathogenic bacteria. Several reports suggest that archaea, gram-negative bacteria, and eukaryotic cells secrete membrane vesicles as a means for cell-free intercellular communication. EVs influence intercellular communication by transferring a myriad of biomolecules including genetic information. Also, EVs have been implicated in many phenomena such as stress response, intercellular competition, lateral gene transfer, and pathogenicity. However, the cellular process of secreting EVs in gram-positive bacteria is less studied. A notion with the thick cell-walled microbes such as gram-positive bacteria is that the EV release is impossible among them. The role of gram-positive EVs in health and diseases is being studied gradually. Being nano-sized, the EVs from gram-positive bacteria carry a diversity of cargo compounds that have a role in bacterial competition, survival, invasion, host immune evasion, and infection. In this review, we summarise the current understanding of the EVs produced by gram-positive bacteria. Also, we discuss the functional aspects of these components while comparing them with gram-negative bacteria.

Keywords: HGT; antibiotic resistance; biofilm; extracellular DNA; immune response; pathogenesis; peptidoglycan; quorum sensing; vaccine; virulence.

Publication types

  • Review

Grants and funding

In part, the study was supported by funds from the Department of Biotechnology, New Delhi, to the Institute of Life Sciences, Bhubaneswar. SB and SA are grateful to the Institute of Life Sciences, Bhubaneswar, for providing Senior Research Fellowships. The funder had no role in study design, data collection, analysis, or decision to publish or prepare the manuscript. We thank our laboratory colleagues for their helpful discussions and critical comments. We apologize that not all of the works related to this field could be discussed or cited due to space limitations.