scholarly journals Incorporation of Plasmid DNA Into Bacterial Membrane Vesicles by Peptidoglycan Defects in Escherichia coli

2021 ◽  
Vol 12 ◽  
Author(s):  
Sharmin Aktar ◽  
Yuhi Okamoto ◽  
So Ueno ◽  
Yuhei O. Tahara ◽  
Masayoshi Imaizumi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Outer Membrane ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Bacterial Membrane ◽  
Gram Negative Bacteria ◽  
Plasmid Copy ◽  
Gram Negative

Membrane vesicles (MVs) are released by various prokaryotes and play a role in the delivery of various cell-cell interaction factors. Recent studies have determined that these vesicles are capable of functioning as mediators of horizontal gene transfer. Outer membrane vesicles (OMVs) are a type of MV that is released by Gram-negative bacteria and primarily composed of outer membrane and periplasm components; however, it remains largely unknown why DNA is contained within OMVs. Our study aimed to understand the mechanism by which DNA that is localized in the cytoplasm is incorporated into OMVs in Gram-negative bacteria. We compared DNA associated with OMVs using Escherichia coli BW25113 cells harboring the non-conjugative, non-mobilized, and high-copy plasmid pUC19 and its hypervesiculating mutants that included ΔnlpI, ΔrseA, and ΔtolA. Plasmid copy per vesicle was increased in OMVs derived from ΔnlpI, in which peptidoglycan (PG) breakdown and synthesis are altered. When supplemented with 1% glycine to inhibit PG synthesis, both OMV formation and plasmid copy per vesicle were increased in the wild type. The bacterial membrane condition test indicated that membrane permeability was increased in the presence of glycine at the late exponential phase, in which cell lysis did not occur. Additionally, quick-freeze deep-etch and replica electron microscopy observations revealed that outer-inner membrane vesicles (O-IMVs) are formed in the presence of glycine. Thus, two proposed routes for DNA incorporation into OMVs under PG-damaged conditions are suggested. These routes include DNA leakage due to increased membrane permeation and O-IMV formation. Additionally, our findings contribute to a greater understanding of the vesicle-mediated horizontal gene transfer that occurs in nature and the utilization of MVs for DNA cargo.

scholarly journals Gene Transfer Potential of Outer Membrane Vesicles of Gram-Negative Bacteria

2021 ◽  
Vol 22 (11) ◽  
pp. 5985
Author(s):  
Federica Dell’Annunziata ◽  
Veronica Folliero ◽  
Rosa Giugliano ◽  
Anna De Filippis ◽  
Cristina Santarcangelo ◽  
...  
Keyword(s):  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Outer Membrane ◽  
Pathogenic Bacteria ◽  
Membrane Vesicles ◽  
Multidrug Resistant ◽  
Outer Membrane Vesicles ◽  
Biologically Active ◽  
Gram Negative Bacteria ◽  
Gram Negative

The increasing spread of multidrug-resistant pathogenic bacteria is one of the major threats to public health worldwide. Bacteria can acquire antibiotic resistance and virulence genes through horizontal gene transfer (HGT). A novel horizontal gene transfer mechanism mediated by outer membrane vesicles (OMVs) has been recently identified. OMVs are rounded nanostructures released during their growth by Gram-negative bacteria. Biologically active toxins and virulence factors are often entrapped within these vesicles that behave as molecular carriers. Recently, OMVs have been reported to contain DNA molecules, but little is known about the vesicle packaging, release, and transfer mechanisms. The present review highlights the role of OMVs in HGT processes in Gram-negative bacteria.

scholarly journals Spheres of Hope, Packets of Doom: the Good and Bad of Outer Membrane Vesicles in Interspecies and Ecological Dynamics

2017 ◽  
Vol 199 (15) ◽  
Author(s):  
Jonathan B. Lynch ◽  
Rosanna A. Alegado
Keyword(s):  
Antimicrobial Activity ◽  
Horizontal Gene Transfer ◽  
Outer Membrane ◽  
Recent Progress ◽  
Membrane Vesicles ◽  
Stress Relief ◽  
Outer Membrane Vesicles ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
By Products

ABSTRACT Outer membrane vesicles (OMVs) are proteoliposome nanoparticles ubiquitously produced by Gram-negative bacteria. Typically bearing a composition similar to those of the outer membrane and periplasm of the cells from which they are derived, OMVs package an array of proteins, lipids, and nucleic acids. Once considered inconsequential by-products of bacterial growth, OMVs have since been demonstrated to mediate cellular stress relief, promote horizontal gene transfer and antimicrobial activity, and elicit metazoan inflammation. Recently, OMVs have gained appreciation as critical moderators of interorganismal dynamics. In this review, we focus on recent progress toward understanding the functions of OMVs with regard to symbiosis and ecological contexts, and we propose potential avenues for future OMV studies.

Electrophysiological Characterization of Transport Across Outer Membrane Channels from Gram-Negative Bacteria in Their Native Environment

2019 ◽  
Author(s):  
Jiajun Wang ◽  
Rémi Terrasse ◽  
Jayesh Arun Bafna ◽  
Lorraine Benier ◽  
Mathias Winterhalter
Keyword(s):  
Outer Membrane ◽  
Lipid Membrane ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Multi Drug Resistance ◽  
Gram Negative Bacteria ◽  
Membrane Channels ◽  
Gram Negative ◽  
Electrophysiological Characterization

Multi-drug resistance in Gram-negative bacteria is often associated with low permeability of the outer membrane. To investigate the role of membrane channels in the uptake of antibiotics, we extract, purify and reconstitute them into artificial planar membranes. To avoid this time-consuming procedure, here we show a robust approach using fusion of native outer membrane vesicles (OMV) into planar lipid bilayer which moreover allows also to some extend the characterization of membrane protein channels in their native environment. Two major membrane channels from <i>Escherichia coli</i>, OmpF and OmpC, were overexpressed from the host and the corresponding OMVs were collected. Each OMV fusion revealed surprisingly single or only few channel activities. The asymmetry of the OMV´s translates after fusion into the lipid membrane with the LPS dominantly present at the side of OMV addition. Compared to conventional reconstitution methods, the channels fused from OMVs containing LPS have similar conductance but a much broader distribution. The addition of Enrofloxacin on the LPS side yields somewhat higher association (<i>k<sub>on</sub></i>) and lower dissociation (<i>k<sub>off</sub></i>) rates compared to LPS-free reconstitution. We conclude that using outer membrane vesicles is a fast and easy approach for functional and structural studies of membrane channels in the native membrane.

scholarly journals Outer Membrane Vesicle Production by Escherichia coli Is Independent of Membrane Instability

2006 ◽  
Vol 188 (15) ◽  
pp. 5385-5392 ◽  
Author(s):  
Amanda J. McBroom ◽  
Alexandra P. Johnson ◽  
Sreekanth Vemulapalli ◽  
Meta J. Kuehn
Keyword(s):  
Escherichia Coli ◽  
Outer Membrane ◽  
Cell Envelope ◽  
Membrane Vesicle ◽  
Membrane Vesicles ◽  
Fold Increase ◽  
Outer Membrane Vesicles ◽  
Host Cells ◽  
Physiological Basis ◽  
Gram Negative

ABSTRACT It has been long noted that gram-negative bacteria produce outer membrane vesicles, and recent data demonstrate that vesicles released by pathogenic strains can transmit virulence factors to host cells. However, the mechanism of vesicle release has remained undetermined. This genetic study addresses whether these structures are merely a result of membrane instability or are formed by a more directed process. To elucidate the regulatory mechanisms and physiological basis of vesiculation, we conducted a screen in Escherichia coli to identify gene disruptions that caused vesicle over- or underproduction. Only a few low-vesiculation mutants and no null mutants were recovered, suggesting that vesiculation may be a fundamental characteristic of gram-negative bacterial growth. Gene disruptions were identified that caused differences in vesicle production ranging from a 5-fold decrease to a 200-fold increase relative to wild-type levels. These disruptions included loci governing outer membrane components and peptidoglycan synthesis as well as the σE cell envelope stress response. Mutations causing vesicle overproduction did not result in upregulation of the ompC gene encoding a major outer membrane protein. Detergent sensitivity, leakiness, and growth characteristics of the novel vesiculation mutant strains did not correlate with vesiculation levels, demonstrating that vesicle production is not predictive of envelope instability.

scholarly journals Biogenesis and multifaceted roles of outer membrane vesicles from Gram-negative bacteria

Microbiology ◽  
2014 ◽  
Vol 160 (10) ◽  
pp. 2109-2121 ◽  
Author(s):  
Heramb M. Kulkarni ◽  
Medicharla V. Jagannadham
Keyword(s):  
Outer Membrane ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Host Cells ◽  
Future Research ◽  
Gram Negative Bacteria ◽  
Biological Functions ◽  
Gram Negative ◽  
Bacterial Quorum ◽  
Membrane Components

Outer membrane vesicles (OMVs) released from Gram-negative bacteria consist of lipids, proteins, lipopolysaccharides and other molecules. OMVs are associated with several biological functions such as horizontal gene transfer, intracellular and intercellular communication, transfer of contents to host cells, and eliciting an immune response in host cells. Although hypotheses have been made concerning the mechanism of biogenesis of these vesicles, research on OMV formation is far from complete. The roles of outer membrane components, bacterial quorum sensing molecules and some specific proteins in OMV biogenesis have been studied. This review discusses the different models that have been proposed for OMV biogenesis, along with details of the biological functions of OMVs and the likely scope of future research.

scholarly journals Development of transport systems of quinolone class antibiotics through outer membrane vesicles (OMVs) in Gram-negative bacteria

2018 ◽  
Author(s):  
Carlos Fernando Macedo da Silva ◽  
Marcelo Lancellotti
Keyword(s):  
Outer Membrane ◽  
Bacterial Growth ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Transport Systems ◽  
Gram Negative Bacteria ◽  
Extracellular Medium ◽  
Gram Negative ◽  
Resistance To Antibiotics ◽  
Cell Reproduction

Multi-resistance to antibiotics in Gram-negative bacteria has been reported in several studies, which make more effective methods of controlling and eliminating these bacteria necessary. To overcome multiresistant profiles, we used OMVs (Outer Membrane Vesicles) as carriers of levofloxacin to encapsulate and transport the drug from the extracellular medium into the cell, overcoming resistance barriers and inhibiting cell reproduction machinery. Prepackaged formulations in this manner were quite effective and, in some cases, totally inhibited bacterial growth by making the drug efficient again.

Sign in / Sign up

Export Citation Format

Share Document