scholarly journals Bacterial plasma membrane is the main cellular target of silver nanoparticles in Escherichia coli and Pseudomonas aeruginosa

2018 ◽  
Author(s):  
Olesja M Bondarenko ◽  
Mariliis Sihtmäe ◽  
Julia Kuzmičiova ◽  
Lina Ragelienė ◽  
Anne Kahru ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Silver Nanoparticles ◽  
Plasma Membrane ◽  
Antimicrobial Properties ◽  
Consumer Products ◽  
Minimal Bactericidal Concentration ◽  
Flow Cytometry Analysis ◽  
E Coli ◽  
Cellular Target

ABSTRACTSilver nanoparticles (AgNP) are widely used in consumer products, mostly due to their excellent antimicrobial properties. One of the well-established antibacterial mechanisms of AgNP is their efficient contact with bacteria and dissolution on cell membranes. To our knowledge, the primary mechanism of cell wall damage and the event(s) initiating bactericidal action of AgNP are not yet elucidated.In this study we used a combination of different assays to reveal the effect of AgNP on i) bacterial envelope in general, ii) outer membrane (OM) and iii) on plasma membrane (PM). We showed that bacterial PM was the main target of AgNP in Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa. AgNP depolarized bacterial PM, induced the leakage of the intracellular K+, inhibited respiration and caused the depletion of the intracellular ATP. In contrast, AgNP had no significant effect on the bacterial OM. Most of the adverse effects on bacterial envelope and PM occurred within the seconds and in the concentration range of 7-160 μM AgNP, depending on the bacteria and assay used, while irreversible inhibition of bacterial growth (minimal bactericidal concentration after 1-h exposure of bacteria to AgNP) occurred at 40 μM AgNP for P. aeruginosa and at 320 μM AgNP for E. coli.Flow cytometry analysis showed that AgNP were binding to P. aeruginosa but not to E. coli cells and were found inside the P. aeruginosa cells. Taking into account that AgNP did not damage OM, we speculate that AgNP entered P. aeruginosa via specific mechanism, e.g., transport through porins.

scholarly journals АНТИМІКРОБНА АКТИВНІСТЬ ЕТАНОЛЬНОГО ЕКСТРАКТУ SERRATULA CORONATA L. (ASTERACEAE) ЗА ІНТРОДУКЦІЇ В ЖИТОМИРСЬКОМУ ПОЛІССІ

2016 ◽  
Vol 6 (01) ◽  
pp. 290-303 ◽  
Author(s):  
I.V. Ivashchenko
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Candida Albicans ◽  
Antimicrobial Properties ◽  
Ethanol Extract ◽  
Antimicrobial Effect ◽  
Minimal Bactericidal Concentration ◽  
Lower Sensitivity ◽  
Serratula Coronata

<p> Antimicrobial properties of <em>Serratula coronata </em>L<em>., </em>introduced in Zhytomyr Polissya, were studied against test cultures of <em>Escherichia coli</em> (coliform bacillus) UCM B-906 (ATCC 25922), <em>Staphylococcus aureus</em>(golden staphylococcus) UCM B-904 (ATCC 25923), <em>Pseudomonas aeruginosa</em> (blue pus bacillus) UCM B-900 (ATCC9027), <em>Candida albicans</em> UCM Y-(ATCC 885-653).</p><p><em>Serratula coronata </em>L.<em> </em>40 % ethanol extract showed potent antimicrobial effect against gram-positive bacteria <em>Staphylococcus aureus</em>. Compared with the solvent, MIC (minimal inhibitory concentration) and MBC (minimal bactericidal concentration) increased 32 and 8 times, respectively. The other microorganisms’ cultures demonstrated much lower sensitivity. The study revealed less significant effect of the extract against <em>Candida albicans, Pseudomonas aeruginosa, </em>and it failed to display any bactericidal/fungicidal effect against gram-negative strains of <em>Escherichia coli, Pseudomonas aeruginosa </em>and fungus <em>Candida albicans.</em>The data obtained experimentally show that further study of <em>Serratula coronata </em>L<em>. </em>and its application as the basis for new pharmaceutical anti-staphylococcus preparations may be considered promising and having a great potential.</p>

Integrated approach to evaluating the toxicity of novel cysteine-capped silver nanoparticles to Escherichia coli and Pseudomonas aeruginosa

The Analyst ◽  
2014 ◽  
Vol 139 (5) ◽  
pp. 954-963 ◽  
Author(s):  
John H. Priester ◽  
Aditi Singhal ◽  
Binghui Wu ◽  
Galen D. Stucky ◽  
Patricia A. Holden
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Silver Nanoparticles ◽  
Bacterial Growth ◽  
Ag Nanoparticles ◽  
Cell Membranes ◽  
Integrated Approach ◽  
E Coli ◽  
Particle Dissolution ◽  
Measured Particle

The toxicity of cysteine capped Ag nanoparticles toE. coliandP. aeruginosawas evaluated using an integrated approach that measured particle dissolution, bacterial growth, and effects on cell membranes.

scholarly journals Plasma membrane is the target of rapid antibacterial action of silver nanoparticles in Escherichia coli and Pseudomonas aeruginosa

2018 ◽  
Vol Volume 13 ◽  
pp. 6779-6790 ◽  
Author(s):  
Olesja M Bondarenko ◽  
Mariliis Sihtmäe ◽  
Julia Kuzmičiova ◽  
Lina Ragelienė ◽  
Anne Kahru ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Silver Nanoparticles ◽  
Plasma Membrane ◽  
Antibacterial Action

scholarly journals Sintesis del óxido de cobre nanoestructurado asistida con irradiación gamma o ultrasonido y sus propiedades antimicrobianas

2019 ◽  
pp. 3-7
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Copper Oxide ◽  
Gamma Irradiation ◽  
Antimicrobial Properties ◽  
Ultrasound Irradiation ◽  
Cuo Nanoparticles ◽  
E Coli

Sintesis del óxido de cobre nanoestructurado asistida con irradiación gamma o ultrasonido y sus propiedades antimicrobianas Synthesis of nanostructured copper oxide assisted with Gamma or ultrasound irradiation and its antimicrobial properties Kety León, Alcides López, Javier Gago, José Solís División de Materiales, Dirección de Investigación y Desarrollo, Instituto Peruano de Energía Nuclear. Av Canadá 1470, San Borja Facultad de Ciencias, Universidad Nacional de Ingeniería. Av. Túpac Amaru 210, Rímac. DOI: https://doi.org/10.33017/RevECIPeru2011.0001/ RESUMEN Se han sintetizado nanopartículas de óxido de cobre (CuO) mediante irradiación gamma o ultrasonido. La actividad antimicrobiana de las nanopartículas de CuO se determinaron mediante el método de excavación en placa cultivo, con 3 cepas microbianas: Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 y Pseudomonas aeruginosa ATCC 27853. La concentración bacteriana inicial fue 1x107 UFC / mL, y fueron sembradas sobre Agar Muller Hinton e incubadas a 37ºC por 24 h. Las nanopartículas de CuO obtenidas mediante ultrasonido son nanoesferas con una mayor actividad antimicrobiana para la bacteria S. aureus que para E. coli y sin actividad frente a P. aeruginosa; mientras que las nanopartículas de CuO obtenidas con radiación gamma con una dosis de 8 kGy tienen actividades antimicrobianas similares para S. aureus y E. coli y las obtenidas a dosis de 15 y 25 kGy solo tienen actividad antimicrobiana frente a E. coli. Descriptores: Nanopartículas, actividad antimicrobiana, sonoquímica, radiación gamma. ABSTRACT Copper oxide (CuO) nanoparticles have been synthesized using gamma irradiation or ultrasound. The antimicrobial activity of CuO nanoparticles was determined by excavation method in plate culture in three microbial strains: Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853. The initial bacterial concentration was 1x107 CFU / mL and seeded onto Muller Hinton Agar and incubated at 37 °C for 24 h. The CuO nanoparticles obtained by ultrasound are nanospheres with a higher antimicrobial activity for S. aureus than for E. coli and no activity against P. aeruginosa, while CuO nanoparticles obtained by gamma irradiation with a dose of 8 kGy have antimicrobial activity similar to S. aureus and E. coli and those obtained at doses of 15 and 25 kGy only have antimicrobial activity against E. coli. Keywords: Nanoparticles, antimicrobial activity, sonochemistry, gamma radiation.

Антимікробна резистентність провідних збудників інфекцій сечових шляхів у Києві (Україна)

2017 ◽  
Vol 1 (2) ◽  
pp. 48-60
Author(s):  
A.G. Salmanov ◽  
A.V. Rudenko
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Klebsiella Pneumoniae ◽  
Staphylococcus Epidermidis ◽  
Klebsiella Oxytoca ◽  
Enterobacter Aerogenes ◽  
Enterobacter Cloacae ◽  
Proteus Vulgaris ◽  
Providencia Rettgeri ◽  
E Coli

Мета роботи — вивчити резистентність до антибіотиків бактеріальних збудників інфекцій сечових шляхів (ІСШ), виділених у пацієнтів урологічного стаціонару в м. Києві. Матеріали і методи. Досліджено 1612 штамів бактерій, виділених із сечі хворих з ІСШ (цистит, уретрит, пієлонефрит), госпіталізованих в урологічне відділення ДУ «Інститут урології НАМН України» у м. Києві протягом 2016 р. Серед пацієнтів переважали жінки — 1201 (74,5 %). Вік хворих становив від 17 до 74 років. Для збору даних використано медичну документацію лікарні. Мікробіологічні дослідження виконано у лабораторії мікробіології ДУ «Інститут урології НАМН України». Аналізували результати культурального дослідження зразків сечі, зібраних за наявності клінічних ознак ІСШ. Дослідження клінічного матеріалу та інтерпретацію отриманих результатів проводили загальноприйнятими методами. Вивчено чутливість уропатогенів до 31 антибіотика дискодифузійним методом відповідно до рекомендацій Інституту клінічних та лабораторних стандартів США (Clinical and Laboratory Standards Institute (CLSI)). Результати та обговорення. Аналіз мікробного спектра сечі виявив домінування серед уропатогенів штамів Escherichia coli (32,0 %), Enterococcus faecalis (19,5 %), Klebsiella pneumoniae (10,9 %), Staphylococcus epidermidis (8,9 %), S. haemolyticus (6,5 %) та Pseudomonas aeruginosa (6,4 %). Частка Enterococcus faecium, Enterobacter aerogenes і Streptococcus viridans становила відповідно 2,5, 2,2 і 1,6 %, Enterobacter cloacae, Klebsiella oxytoca, Acinetobacter baumannii, Proteus vulgaris та Providencia rettgeri — менше 1,0 %. У більшості випадків (69,7 %) мікроорганізми виділено у монокультурі, у решті випадків — у мікробних асоціа- ціях. Високу резистентність до тестованих антибіотиків виявили штами E. aerogenes (45,1 %), E. cloacae (45,7 %), E. faecium (40,9 %), E. faecalis (40,7 %), E. coli (39,9 %), P. aeruginosa (34,0 %), K. pneumoniae (28,6 %). Найбільш активними до уропатогенів були іміпенем (E. coli — 87,6 %, P. aeruginosa — 75,7 %, E. cloacae — 67,3 %, E. aerogenes — 72,6 %, K. pneumoniae — 93,2 %), меропенем (E. coli — 89,1 %, P. aeruginosa — 76,7 %, K. pneumoniae — 82,6 %), лефлоцин (E. coli — 74,5 %, ентерококи — 78,7 %, P. aeruginosa — 76,7 %, E. cloacae — 73,9 %, E. aerogenes — 80,4 %, K. pneumoniae — 83,5 %), амоксицилін/клавуланат (ентерококи — 84,6 %), фурагін (ентерококи — 82,6 %), цефоперазон (K. pneumoniae — 89,2 %, P. aeruginosa — 73,8 %), цефтріаксон (K. pneumoniae — 80,1 %). Висновки. Антибіотикорезистентність збудників ІСШ — важлива терапевтична проблема. Найбільшою активністю до уропатогенів характеризуються іміпенем, меропенем, лефлоцин, амоксицилін/ клавуланат, фурагін, цефоперазон, цефтріаксон, які можна розглядати як препарат вибору для призначення стартової терапії ІСШ. Необхідно здійснювати постійний моніторинг за резистентністю до дії антибіотиків. Політику використання антибіотиків у кожному стаціонарі слід визначати залежно від локальних даних щодо резистентності до протимікробних препаратів.

Antimicrobial Activity of Silver Nanoparticles Prepared Under an Ultrasonic Field

2011 ◽  
Vol 4 (3) ◽  
pp. 1491-1496
Author(s):  
Umadevi M ◽  
Rani T ◽  
Balakrishnan T ◽  
Ramanibai R
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Reduction Method ◽  
Therapeutic Potential ◽  
Chemical Reduction ◽  
Ultrasonic Field ◽  
Great Promise ◽  
Chemical Reduction Method ◽  
E Coli

Nanotechnology has great promise for improving the therapeutic potential of medicinal molecules and related agents. In this study, silver nanoparticles of different sizes were synthesized in an ultrasonic field using the chemical reduction method with sodium borohydride as a reducing agent. The size effect of silver nanoparticles on antimicrobial activity were tested against the microorganisms Staphylococcus aureus (MTCC No. 96), Bacillus subtilis (MTCC No. 441), Streptococcus mutans (MTCC No. 497), Escherichia coli (MTCC No. 739) and Pseudomonas aeruginosa (MTCC No. 1934). The results shows that B. subtilis, and E. coli were more sensitive to silver nanoparticles and its size, indicating the superior antimicrobial efficacy of silver nanoparticles. 

scholarly journals Transcriptome analysis of Escherichia coli K1 after therapy with hesperidin conjugated with silver nanoparticles

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Abdulkader Masri ◽  
Naveed Ahmed Khan ◽  
Muhammad Zarul Hanifah Md Zoqratt ◽  
Qasim Ayub ◽  
Ayaz Anwar ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Silver Nanoparticles ◽  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Neonatal Meningitis ◽  
E Coli ◽  
Drug Candidates ◽  
Metabolic Genes ◽  
Genetic Mechanisms ◽  
Cell Stress Response

Abstract Backgrounds Escherichia coli K1 causes neonatal meningitis. Transcriptome studies are indispensable to comprehend the pathology and biology of these bacteria. Recently, we showed that nanoparticles loaded with Hesperidin are potential novel antibacterial agents against E. coli K1. Here, bacteria were treated with and without Hesperidin conjugated with silver nanoparticles, and silver alone, and 50% minimum inhibitory concentration was determined. Differential gene expression analysis using RNA-seq, was performed using Degust software and a set of genes involved in cell stress response and metabolism were selected for the study. Results 50% minimum inhibitory concentration with silver-conjugated Hesperidin was achieved with 0.5 μg/ml of Hesperidin conjugated with silver nanoparticles at 1 h. Differential genetic analysis revealed the expression of 122 genes (≥ 2-log FC, P< 0.01) in both E. coli K1 treated with Hesperidin conjugated silver nanoparticles and E. coli K1 treated with silver alone, compared to untreated E. coli K1. Of note, the expression levels of cation efflux genes (cusA and copA) and translocation of ions, across the membrane genes (rsxB) were found to increase 2.6, 3.1, and 3.3- log FC, respectively. Significant regulation was observed for metabolic genes and several genes involved in the coordination of flagella. Conclusions The antibacterial mechanism of nanoparticles maybe due to disruption of the cell membrane, oxidative stress, and metabolism in E. coli K1. Further studies will lead to a better understanding of the genetic mechanisms underlying treatment with nanoparticles and identification of much needed novel antimicrobial drug candidates.

scholarly journals High-density transposon libraries utilising outward-oriented promoters identify mechanisms of action and resistance to antimicrobials

2020 ◽  
Vol 367 (22) ◽  
Author(s):  
Chris Coward ◽  
Gopujara Dharmalingham ◽  
Omar Abdulle ◽  
Tim Avis ◽  
Stephan Beisken ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Pathogenic Bacteria ◽  
Selective Advantage ◽  
Mechanisms Of Action ◽  
Over Expression ◽  
E Coli ◽  
Synthase Inhibitor ◽  
Established Technique ◽  
Bacterial Transposon

ABSTRACT The use of bacterial transposon mutant libraries in phenotypic screens is a well-established technique for determining which genes are essential or advantageous for growth in conditions of interest. Standard, inactivating, transposon libraries cannot give direct information about genes whose over-expression gives a selective advantage. We report the development of a system wherein outward-oriented promoters are included in mini-transposons, generation of transposon mutant libraries in Escherichia coli and Pseudomonas aeruginosa and their use to probe genes important for growth under selection with the antimicrobial fosfomycin, and a recently-developed leucyl-tRNA synthase inhibitor. In addition to the identification of known mechanisms of action and resistance, we identify the carbon–phosphorous lyase complex as a potential resistance liability for fosfomycin in E. coli and P. aeruginosa. The use of this technology can facilitate the development of novel mechanism-of-action antimicrobials that are urgently required to combat the increasing threat worldwide from antimicrobial-resistant pathogenic bacteria.

scholarly journals Fabrication of a Novel AgBr/Ag2MoO4@InVO4 Composite with Excellent Visible Light Photocatalytic Property for Antibacterial Use

Nanomaterials ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1541
Author(s):  
Jie Zhang ◽  
Jia Wang ◽  
Qingjun Zhu ◽  
Binbin Zhang ◽  
Huihui Xu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Degradation Rate ◽  
Photocatalytic Property ◽  
Photocatalytic Reaction ◽  
Composite Photocatalyst ◽  
E Coli ◽  
Radical Trapping ◽  
Visible Light Photocatalytic

A novel AgBr/Ag2MoO4@InVO4 composite photocatalyst with different heterojunction structures was successfully constructed by compounding InVO4 with Ag2MoO4 and AgBr. According to the degradation, antibacterial and free radical trapping data, the photocatalytic antibacterial and antifouling activities of AgBr/Ag2MoO4@InVO4 composite were evaluated, and the corresponding photocatalytic reaction mechanism was proposed. Adding AgBr/Ag2MoO4@InVO4 composite, the degradation rate of ciprofloxacin (CIP) achieved 95.5% within 120 min. At the same time, the antibacterial rates of Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) achieved 99.99%. The AgBr/Ag2MoO4@InVO4 composite photocatalyst showed promising usage in photocatalytic antibacterial and purification areas.

Sign in / Sign up

Export Citation Format

Share Document