Effect of surface lipopolysaccharide on the nature of membrane vesicles liberated from the Gram-negative bacterium Pseudomonas aeruginosa

2003 ◽  
Vol 52 (5) ◽  
pp. 465-469 ◽  
Author(s):  
T. T. Nguyen
2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Genevieve Johnson ◽  
Carine R. Mores ◽  
Alan J. Wolfe ◽  
Catherine Putonti

Pseudomonas aeruginosa is a Gram-negative bacterium that has the ability to survive in and readily adapt to a variety of environmental conditions. Here, we report 2 genome sequences of P. aeruginosa strains, UMB1046 and UMB5686, isolated from the female urogenital tract.


2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Lingyue Yan ◽  
Ming Yan ◽  
Lin Xu ◽  
Li Wei ◽  
Liting Zhang

Pseudomonas aeruginosa is a Gram-negative bacterium, which uses a variety of organic chemicals as carbon sources. Here, we report the genome sequence of the Cu1510 isolate from wastewater containing a high concentration of N , N -dimethyl formamide.


2013 ◽  
Vol 79 (6) ◽  
pp. 1874-1881 ◽  
Author(s):  
Carla Pérez-Cruz ◽  
Ornella Carrión ◽  
Lidia Delgado ◽  
Gemma Martinez ◽  
Carmen López-Iglesias ◽  
...  

ABSTRACTOuter membrane vesicles (OMVs) from Gram-negative bacteria are known to be involved in lateral DNA transfer, but the presence of DNA in these vesicles has remained difficult to explain. An ultrastructural study of the Antarctic psychrotolerant bacteriumShewanella vesiculosaM7Thas revealed that this Gram-negative bacterium naturally releases conventional one-bilayer OMVs through a process in which the outer membrane is exfoliated and only the periplasm is entrapped, together with a more complex type of OMV, previously undescribed, which on formation drag along inner membrane and cytoplasmic content and can therefore also entrap DNA. These vesicles, with a double-bilayer structure and containing electron-dense material, were visualized by transmission electron microscopy (TEM) after high-pressure freezing and freeze-substitution (HPF-FS), and their DNA content was fluorometrically quantified as 1.8 ± 0.24 ng DNA/μg OMV protein. The new double-bilayer OMVs were estimated by cryo-TEM to represent 0.1% of total vesicles. The presence of DNA inside the vesicles was confirmed by gold DNA immunolabeling with a specific monoclonal IgM against double-stranded DNA. In addition, a proteomic study of purified membrane vesicles confirmed the presence of plasma membrane and cytoplasmic proteins in OMVs from this strain. Our data demonstrate the existence of a previously unobserved type of double-bilayer OMV in the Gram-negative bacteriumShewanella vesiculosaM7Tthat can incorporate DNA, for which we propose the name outer-inner membrane vesicle (O-IMV).


2016 ◽  
Vol 4 (4) ◽  
Author(s):  
Brock A. Arivett ◽  
Dave C. Ream ◽  
Steven E. Fiester ◽  
Destaalem Kidane ◽  
Luis A. Actis

Pseudomonas aeruginosa , a Gram-negative bacterium that causes severe hospital-acquired infections, is grouped as an ESKAPE ( Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa , and Enterobacter species) pathogen because of its extensive drug resistance phenotypes and effects on human health worldwide. Five multidrug resistant P. aeruginosa strains isolated from wounded military personnel were sequenced and annotated in this work.


1986 ◽  
Vol 39 (8) ◽  
pp. 1205 ◽  
Author(s):  
S Stojkovski ◽  
RJ Magee ◽  
J Liesegang

The uptake of molybdenum by certain bacteria hinders its role as a trace metal in the micronutrients for plant growth. The binding of molybdenum by the Gram-negative bacterium Pseudomonas aeruginosa, PAO1, has been investigated. A molybdenum complex of uronic acid, which forms in the extracellular polysaccharide layer (slime), was isolated and characterized by a variety of techniques. Comparisons with 'mimic' compounds of uronic acids suggest that Pseudomonas aeruginosa, PAO1, produces a binuclear, di-oxo-bridged magnesium salt MgMo2O4(C6H8O7)2.5H2O; this indicates the important role of uronic acids in metallic uptake by bacteria.


2021 ◽  
Author(s):  
Ozlem Gur Ozdal ◽  
Omer Faruk ALGUR

Abstract Extensive applications of pesticides have led to the contamination of ecosystem. Therefore, the isolation of new pesticide degrading bacteria is important. For the biodegradation of α-endosulfan and α-cypermethrin, new bacteria isolates were isolated from grasshopper (Poecilimon tauricola). According to different tests, these isolated bacteria were identified as Pseudomonas aeruginosa B5, Acinetobacter johnsonii B6, Acinetobacter schindleri B7, Bacillus megaterium B9 and Brevibacillus parabrevis B12. The first two of these bacteria have been isolated as those that can use only α-endosulfan and the last two only use α-cypermethrin. Moreover, A. schindleri B7 was determined to be able to degrade both pesticides. When glucose was added to non-sulfur medium containing α-endosulfan (100 mg/L) and minimal salt medium containing α-cypermethrin (100 mg/L), both pesticide degradation and bacterial growth was increased. As a result, A. schindleri, a new gram negative bacterium, can inevitably be used in the biological treatment of environments exposed to pesticides.


2020 ◽  
pp. 1041-1044
Author(s):  
G.C.K.W. Koh ◽  
Sharon J. Peacock

Pseudomonas aeruginosa is a highly versatile environmental Gram-negative bacterium that can be isolated from a wide range of habitats, including soil, marshes, and the ocean, as well as from plant and animal tissues. It is resistant to many disinfectants and antibiotics, giving it a selective advantage in hospitals. It rarely causes infection in the healthy host but is a major opportunistic pathogen. Diagnosis is usually straightforward when the organism is cultured from samples collected from normally sterile sites, but is often challenging when infection is suspected in non-sterile sites such as a catheterized urinary tract, burns, or skin ulcers, because P. aeruginosa may be either a pathogen or an innocent bystander. Treatment can be challenging as P. aeruginosa is intrinsically resistant to a broad range of antimicrobials.


Microbiology ◽  
2011 ◽  
Vol 157 (7) ◽  
pp. 2172-2180 ◽  
Author(s):  
Sivan Elias ◽  
Elena Degtyar ◽  
Ehud Banin

Bacteria acquire iron through a highly specific mechanism involving iron-chelating molecules termed siderophores. The Gram-negative bacterium Pseudomonas aeruginosa can utilize siderophores produced by other micro-organisms to facilitate iron uptake. Here we show that a P. aeruginosa strain deficient in siderophore production can use the Vibrio cholerae siderophore vibriobactin as an iron source. In addition, we identified a P. aeruginosa gene, PA4156 (fvbA), encoding a protein highly homologous to the V. cholerae vibriobactin receptor (ViuA). A P. aeruginosa mutant in the two endogenous siderophores (pyoverdine and pyochelin) and in fvbA was unable to utilize vibriobactin as an iron source. Additionally, preliminary analyses revealed the involvement of vibriobactin, Fur protein and an IclR-type regulator, FvbR (PA4157), in fvbA regulation.


2008 ◽  
Vol 190 (11) ◽  
pp. 3969-3978 ◽  
Author(s):  
Yosuke Tashiro ◽  
Nobuhiko Nomura ◽  
Ryoma Nakao ◽  
Hidenobu Senpuku ◽  
Reiko Kariyama ◽  
...  

ABSTRACT Pseudomonas aeruginosa is an opportunistic bacterial pathogen that is one of the most refractory to therapy when it forms biofilms in the airways of cystic fibrosis patients. To date, studies regarding the production of an immunogenic and protective antigen to inhibit biofilm formation by P. aeruginosa have been superficial. The previously uncharacterized outer membrane protein (OMP) Opr86 (PA3648) of P. aeruginosa is a member of the Omp85 family, of which homologs have been found in all gram-negative bacteria. Here we verify the availability of Opr86 as a protective antigen to inhibit biofilm formation by P. aeruginosa PAO1 and several other isolates. A mutant was constructed in which Opr86 expression could be switched on or off through a tac promoter-controlled opr86 gene. The result, consistent with previous Omp85 studies, showed that Opr86 is essential for viability and plays a role in OMP assembly. Depletion of Opr86 resulted in streptococci-like morphological changes and liberation of excess membrane vesicles. A polyclonal antibody against Opr86 which showed reactivity to PAO1 cells was obtained. The antibody inhibited biofilm formation by PAO1 and the other clinical strains tested. Closer examination of early attachment revealed that cells treated with the antibody were unable to attach to the surface. Our data suggest that Opr86 is a critical OMP and a potential candidate as a protective antigen against biofilm formation by P. aeruginosa.


Author(s):  
Chandni Sharma ◽  
Ashish K Shukla ◽  
Amitabha Acharya

Successful and effective treatment of different types of infections depends upon fast and selective identification of the microorganisms. Pseudomonas aeruginosa is a gram-negative bacterium which is involved in number of...


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