scholarly journals On the Offensive: the Role of Outer Membrane Vesicles in the Successful Dissemination of New Delhi Metallo-β-lactamase (NDM-1)

mBio ◽  
2021 ◽  
Author(s):  
Melina M. B. Martínez ◽  
Robert A. Bonomo ◽  
Alejandro J. Vila ◽  
Paulo C. Maffía ◽  
Lisandro J. González

Resistance to carbapenems, last-resort antibiotics, is spreading worldwide, raising great concern. NDM-1 is one of the most potent and widely disseminated carbapenem-hydrolyzing enzymes spread among many bacteria and is secreted to the extracellular medium within outer membrane vesicles.

Molecules ◽  
2019 ◽  
Vol 24 (10) ◽  
pp. 1972 ◽  
Author(s):  
Jūratė Skerniškytė ◽  
Emilija Karazijaitė ◽  
Julien Deschamps ◽  
Renatas Krasauskas ◽  
Romain Briandet ◽  
...  

Acinetobacter baumannii is a nosocomial human pathogen of increasing concern due to its multidrug resistance profile. The outer membrane protein A (OmpA) is an abundant bacterial cell surface component involved in A. baumannii pathogenesis. It has been shown that the C-terminal domain of OmpA is located in the periplasm and non-covalently associates with the peptidoglycan layer via two conserved amino acids, thereby anchoring OmpA to the cell wall. Here, we investigated the role of one of the respective residues, D268 in OmpA of A. baumannii clinical strain Ab169, on its virulence characteristics by complementing the ΔompA mutant with the plasmid-borne ompAD268A allele. We show that while restoring the impaired biofilm formation of the ΔompA strain, the Ab169ompAD268A mutant tended to form bacterial filaments, indicating the abnormalities in cell division. Moreover, the Ab169 OmpA D268-mediated association to peptidoglycan was required for the manifestation of twitching motility, desiccation resistance, serum-induced killing, adhesion to epithelial cells and virulence in a nematode infection model, although it was dispensable for the uptake of β-lactam antibiotics by outer membrane vesicles. Overall, the results of this study demonstrate that the OmpA C-terminal domain-mediated association to peptidoglycan is critical for a number of virulent properties displayed by A. baumannii outside and within the host.


2017 ◽  
Author(s):  
Laura E. Yates ◽  
Dominic C. Mills ◽  
Matthew P. DeLisa

AbstractBacteria have garnered increased interest in recent years as a platform for the biosynthesis of a variety of glycomolecules such as soluble oligosaccharides, surface-exposed carbohydrates and glycoproteins. The ability to flexibly engineer commonly used laboratory species such asEscherichia colito efficiently synthesize non-native sugar structures by recombinant expression of enzymes from various carbohydrate biosynthesis pathways has allowed for the facile generation of important products such as conjugate vaccines, glycosylated outer membrane vesicles, and a variety of other research reagents for studying and understanding the role of glycans in living systems. This chapter highlights some of the key discoveries and technologies for equipping bacteria with the requisite biosynthetic machinery to generate such products. As the bacterial glyco-toolbox continues to grow, these technologies are expected to expand the range of glycomolecules produced recombinantly in bacterial systems, thereby opening up this platform to an even larger number of applications.


1998 ◽  
Vol 180 (18) ◽  
pp. 4872-4878 ◽  
Author(s):  
Alain Bernadac ◽  
Marthe Gavioli ◽  
Jean-Claude Lazzaroni ◽  
Satish Raina ◽  
Roland Lloubès

ABSTRACT Mutations in the tol-pal genes induce pleiotropic effects such as release of periplasmic proteins into the extracellular medium and hypersensitivity to drugs and detergents. Other outer membrane defective strains such as tolC, lpp, and rfa mutations are also altered in their outer membrane permeability. In this study, electron microscopy and Western blot analyses were used to show that strains with mutations in each of thetol-pal genes formed outer membrane vesicles after growth in standard liquid or solid media. This phenotype was not observed intolC and rfaD cells in the same conditions. AtolA deletion in three different Escherichia coli strains was shown to lead to elevated amounts of vesicles. These results, together with plasmid complementation experiments, indicated that the formation of vesicles resulted from the defect of any of the Tol-Pal proteins. The vesicles contained outer membrane trimeric porins correctly exposed at the cell surface. Pal outer membrane lipoprotein was also immunodetected in the vesicle fraction oftol strains. The results are discussed in view of the role of the Tol-Pal transenvelope proteins in maintaining outer membrane integrity by contributing to target or integrate newly synthesized components of this structure.


2020 ◽  
Vol 21 (8) ◽  
pp. 2822 ◽  
Author(s):  
Si Won Kim ◽  
Jung Seok Lee ◽  
Seong Bin Park ◽  
Ae Rin Lee ◽  
Jae Wook Jung ◽  
...  

Gram-negative bacteria have an outer membrane inhibiting the entry of antibiotics. Porins, found within the outer membrane, are involved in regulating the permeability of β-lactam antibiotics. β-lactamases are enzymes that are able to inactivate the antibacterial properties of β-lactam antibiotics. Interestingly, porins and β-lactamase are found in outer membrane vesicles (OMVs) of β-lactam-resistant Escherichia coli and may be involved in the survival of susceptible strains of E. coli in the presence of antibiotics, through the hydrolysis of the β-lactam antibiotic. In this study, OMVs isolated from β-lactam-resistant E. coli and from mutants, lacking porin or β-lactamase, were evaluated to establish if the porins or β-lactamase in OMVs were involved in the degradation of β-lactam antibiotics. OMVs isolated from E. coli deficient in β-lactamase did not show any degradation ability against β-lactam antibiotics, while OMVs lacking OmpC or OmpF showed significantly lower levels of hydrolyzing activity than OMVs from parent E. coli. These data reveal an important role of OMVs in bacterial defense mechanisms demonstrating that the OmpC and OmpF proteins allow permeation of β-lactam antibiotics into the lumen of OMVs, and antibiotics that enter the OMVs can be degraded by β-lactamase.


Resonance ◽  
2015 ◽  
Vol 20 (8) ◽  
pp. 711-725 ◽  
Author(s):  
M. V. Jagannadham ◽  
M. K. Chattopadhyay

mBio ◽  
2016 ◽  
Vol 7 (4) ◽  
Author(s):  
Wael Elhenawy ◽  
Michael Bording-Jorgensen ◽  
Ezequiel Valguarnera ◽  
M. Florencia Haurat ◽  
Eytan Wine ◽  
...  

ABSTRACTOuter membrane vesicles (OMV) are proposed to mediate multiple functions during pathogenesis and symbiosis. However, the mechanisms responsible for OMV formation remain poorly understood. It has been shown in eukaryotic membranes that lipids with an inverted-cone shape favor the formation of positive membrane curvatures. Based on these studies, we formulated the hypothesis that lipid A deacylation might impose shape modifications that result in the curvature of the outer membrane (OM) and subsequent OMV formation. We tested the effect of lipid A remodeling on OMV biogenesis employingSalmonella entericaserovar Typhimurium as a model organism. Expression of the lipid A deacylase PagL resulted in increased vesiculation, without inducing an envelope stress response. Mass spectrometry analysis revealed profound differences in the patterns of lipid A in OM and OMV, with accumulation of deacylated lipid A forms exclusively in OMV. OMV biogenesis by intracellular bacteria upon macrophage infection was drastically reduced in apagLmutant strain. We propose a novel mechanism for OMV biogenesis requiring lipid A deacylation in the context of a multifactorial process that involves the orchestrated remodeling of the outer membrane.IMPORTANCEThe role of lipid remodeling in vesiculation is well documented in eukaryotes. Similarly, bacteria produce membrane-derived vesicles; however, the molecular mechanisms underlying their production are yet to be determined. In this work, we investigated the role of outer membrane remodeling in OMV biogenesis inS. Typhimurium. We showed that the expression of the lipid A deacylase PagL results in overvesiculation with deacylated lipid A accumulation exclusively in OMV. AnS. Typhimurium ΔpagLstrain showed a significant reduction in intracellular OMV secretion relative to the wild-type strain. Our results suggest a novel mechanism for OMV biogenesis that involves outer membrane remodeling through lipid A modification. Understanding how OMV are produced by bacteria is important to advance our understanding of the host-pathogen interactions.


2012 ◽  
Vol 195 (2) ◽  
pp. 213-219 ◽  
Author(s):  
Aimee K. Wessel ◽  
Jean Liew ◽  
Taejoon Kwon ◽  
Edward M. Marcotte ◽  
Marvin Whiteley

ABSTRACTGram-negative bacteria produce outer membrane vesicles (OMVs) that package and deliver proteins, small molecules, and DNA to prokaryotic and eukaryotic cells. The molecular details of OMV biogenesis have not been fully elucidated, but peptidoglycan-associated outer membrane proteins that tether the outer membrane to the underlying peptidoglycan have been shown to be critical for OMV formation in multipleEnterobacteriaceae. In this study, we demonstrate that the peptidoglycan-associated outer membrane proteins OprF and OprI, but not OprL, impact production of OMVs by the opportunistic pathogenPseudomonas aeruginosa. Interestingly, OprF does not appear to be important for tethering the outer membrane to peptidoglycan but instead impacts OMV formation through modulation of the levels of thePseudomonasquinolone signal (PQS), a quorum signal previously shown by our laboratory to be critical for OMV formation. Thus, the mechanism by which OprF impacts OMV formation is distinct from that for other peptidoglycan-associated outer membrane proteins, including OprI.


Vaccine ◽  
2009 ◽  
Vol 27 (13) ◽  
pp. 1912-1922 ◽  
Author(s):  
Vanessa Durand ◽  
Joanne MacKenzie ◽  
Joel de Leon ◽  
Circe Mesa ◽  
Valérie Quesniaux ◽  
...  

Author(s):  
Carlos Fernando Macedo da Silva ◽  
Marcelo Lancellotti

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.


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