Medical Function of Bacterial Extracellular Vesicles

Abstract

Extracellular vesicles are nanoscale particles which were identified about fifty years ago. The studies have shown that all of the gram-negative bacteria secrete extracellular vesicles during their normal growth. Today, the production of membrane vesicles has been reported by gram-positive bacteria, parasites, fungi, and mycobacteria. Since these nanoscale particles carry many of the bacterial components such as DNA, RNA, protein, endotoxin, and virulence molecules, they play a very important role in interacting with the environment and other bacteria. For this reason, many of these vesicles are considered as the transmission of pathogens, antigenic protein compounds, and the development of non-cellular vaccines, as well as drug delivery agents. The studies, have been carried in this field so far, have been focused on the pathogenic and physiological roles of these nanostructures in cross-species relationships. The focus of this article is on the role of extracellular bacterial vesicles and pathological and physiological functions which contribute to the interactions between bacteria and bacteriumhost. Since these nanostructures play significant role in pathogenesis, gene transduction, regulation of gene expression, immune response regulation, and cellular signaling, further studies are needed on the medical application of these nanostructures as a new generation of vaccines, adjuvants, drug delivery agents.

[Retracted] Investigating the Possibility of Green Synthesis of Silver Nanoparticles Using Vaccinium arctostaphlyos Extract and Evaluating Its Antibacterial Properties

“…Actually, the production of these vesicles can augment the survival of bacteria when attacked by phages. These structures can remove antibacterial agents such as supplements and antibiotics, as well [ 63 ]. It has even been reported that S. aureus extracellular vesicles contain beta-lactamase which causes the survival of ampicillin-sensitive gram-positive and gram-negative bacteria in the presence of ampicillin [ 64 – 66 ] [ 60 – 62 ].…”

“…It has even been reported that S. aureus extracellular vesicles contain beta-lactamase which causes the survival of ampicillin-sensitive gram-positive and gram-negative bacteria in the presence of ampicillin [ 64 – 66 ] [ 60 – 62 ]. Evidence also suggests that the secretion of extracellular vesicles is a completely conserved evolutionary process in gram-positive bacteria [ 64 , 67 ] [ 60 , 63 ]. Therefore, the higher sensitivity of gram-positive bacteria as compared to gram-negatives in this study may be due to the role of silver nanoparticles in further reducing the production of extracellular vesicles in gram-positive bacteria.…”

A polyethylene glycol-based method for extraction of extracellular vesicles from Lactobacillus casei as vaccine delivery vehicle

“…These structures do usually contain varied cargos, such as lipoproteins, nucleic acids, toxins and communication signals which are of great importance for the microbial pathogenesis and physiology [10]. Moreover, we have demonstrated that EVs can also be used as a delivery system [11]. It has been shown that E. coli EVs could be used as a vaccine vehicle system; however, due to presence of lipopolysaccharides in these nanostructures, a number of structural changes are needed [12].…”