scholarly journals The Effect of Silver and Zinc Nanoparticles on The Structural Characteristics of Bacterial Cells

2019 ◽  
Vol 9 (1) ◽  
pp. 3783-3789
Keyword(s):  
Silver Nanoparticles ◽  
Morphological Changes ◽  
Structural Characteristics ◽  
Membrane Surface ◽  
Bacterial Cells ◽  
Zinc Nanoparticles ◽  
E Coli ◽  
Mdbk Cells ◽  
Cell Membrane Surface ◽  
Nanoparticles Of Silver

The paper presents the results of studying the influence of nanoparticles of silver and zinc on the culture of Madin-Darby Bovine Kidney (MDBK) and bacterial cells of E. coli at various dilution rates and various incubation times. The interaction of MDBK cells with the nanoparticles of zinc has a strong deleterious effect on the cells and causes morphological changes in them. At the same time, no toxic effects were observed after the interaction of silver nanoparticles and the cells. During incubation of E. coli bacterial cells with zinc nanoparticles, not only changes in the morphology of the cell membrane surface but also the destruction of bacterial cells were observed. During incubation with silver nanoparticles at various dilution rates for various times, changes in the cell shape from rod-shaped to rounded, without symptoms of destruction were noted.

scholarly journals Altered Na+/K+-ATPase expression plays a role in rumen epithelium adaptation in sheep fed hay ad libitum or a mixed hay/concentrate diet

2011 ◽  
Vol 56 (No. 1) ◽  
pp. 36-48 ◽  
Author(s):  
J. Kuzinski ◽  
R. Zitnan ◽  
T. Viergutz ◽  
J. Legath ◽  
M. Schweigel
Keyword(s):  
Cell Membrane ◽  
Mrna Expression ◽  
Surface Area ◽  
Morphological Changes ◽  
Membrane Surface ◽  
Membrane Surface Area ◽  
Cell Layers ◽  
Ad Libitum ◽  
Atpase Localization ◽  
Cell Membrane Surface

In this study we investigated rumen papillae morphology and the localization and expression of the<br />Na<sup>+/</sup>K<sup>+</sup>-ATPase&nbsp;in eight sheep fed hay ad libitum (h) or hay ad libitum plus additional concentrate (h/c). Four sheep were provided with the ad libitum h-diet for the complete three-week experimental period. The second group of four sheep received the h-diet for only one week and was fed the mixed hay/concentrate (h/c) diet for another two weeks. The amount of concentrate supplement was stepwise increased from 150 to 1000 g/day and given in two meals. Following slaughter rumen papillae from the atrium ruminis (AR), the rumen ventralis (RV) and the ventral blind sac (BSV) were fixed and examined for morphological changes and Na<sup>+</sup>/K<sup>+</sup>-ATPase localization by morphometric methods and immunohistochemistry. Ruminal epithelial cells (REC) originating from the strata basale to granulosum were also isolated. Cellular Na<sup>+</sup>/K<sup>+</sup>-ATPase expression (mRNA and protein) and differentiation state were determined by RT-PCR, Western blot, and flow cytometry. Compared with data from h-fed sheep, morphometric analysis revealed an increased length and width of rumen papillae in h/c-fed sheep, resulting in a marked 41% and 62% increase in rumen papillae surface in AR and RV, respectively. The rumen mucosa of h/c-fed sheep was characterized by a predominant stratum corneum (42 &plusmn; 0.7 &micro;m vs. 28 &plusmn; 0.5 &micro;m), but the thickness of the metabolically active cell layers remained unchanged. REC suspensions from sheep fed the h/c diet generally contained more cells (7.30 &plusmn; 0.83 vs. 3.49 &plusmn; 0.52 &times; 10<sup>7</sup>/ml; P &lt; 0.001) and an increased proportion of REC positive for basal cytokeratin and for the differentiation marker cytokeratin 10 (P &lt; 0.05). Cellular (cell membrane) and epithelial (stratum basale to stratum granulosum) Na<sup>+</sup>/K<sup>+</sup>-ATPase localization was similar between rumen regions and was not changed by concentrate feeding. After two weeks on the h/c-diet, a 96% increase in the absolute number of Na<sup>+</sup>/K<sup>+</sup>-ATPase-positive REC (6.56 &plusmn; 0.84 vs. 3.35 &plusmn; 0.51 &times; 10<sup>7</sup>/ml; P = 0.003) and a 61% elevation (P = 0.043) in Na<sup>+</sup>/K<sup>+</sup>-ATPase protein expression in REC from the upper third of the suprabasal cell layers were found. Moreover, a two-fold (P = 0.001) elevation in cell membrane surface area accompanied by a reduction (1.19 &times; 10<sup>&ndash;7</sup> &plusmn; 1.72 &times; 10<sup>&ndash;9</sup> arbitrary units (AU)/cm2 vs. 1.73 &times; 10<sup>&ndash;7</sup> &plusmn; 8.16 &times; 10<sup>&ndash;9</sup> AU/cm<sup>2</sup> in the h-group; P &lt; 0.001) in specific Na<sup>+</sup>/K<sup>+</sup>-ATPase fluorescence per cm<sup>2</sup> of cell membrane surface area was observed after h/c-feeding. Na<sup>+</sup>/K<sup>+</sup>-ATPase &alpha; subunit mRNA expression was also reduced (P &lt; 0.0001) from 0.154 &plusmn; 0.013 to 0.057 &plusmn; 0.004 pg per pg S18 mRNA control in the h/c-compared with the h-group. Thus, the h/c-diet led to a rapid increase in REC number and total cell membrane surface area in metabolically active and resorptive cell layers and was accompanied by a reduction in Na<sup>+</sup>/K<sup>+</sup>-ATPase mRNA expression and abundance per cell membrane surface area.

Heterologous expression of the surface-layer-like protein SllB induces the formation of long filaments of Escherichia coli consisting of protein-stabilized outer membrane

Microbiology ◽  
2010 ◽  
Vol 156 (12) ◽  
pp. 3584-3595 ◽  
Author(s):  
Franziska Linda Lederer ◽  
Tobias Jan Günther ◽  
Katrin Flemming ◽  
Johannes Raff ◽  
Karim Fahmy ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Heterologous Expression ◽  
Morphological Changes ◽  
Single Cells ◽  
Stationary Growth Phase ◽  
Foreign Protein ◽  
Bacterial Cells ◽  
E Coli ◽  
Composition And Structure ◽  
Micro Organisms

Escherichia coli is one of the best studied micro-organisms and is the most widely used host in genetic engineering. The Gram-negative single cells are rod-shaped, and filaments are usually not found. Here, we describe the reproducible formation of elongated E. coli cells. During heterologous expression of the silent surface (S)-layer protein gene sllB from Lysinibacillus sphaericus JG-A12 in E. coli BL21(DE3), the cells were arranged as long chains which were surrounded by highly stable sheaths. These filaments had a length of >100 μm. In the stationary growth phase, microscopic analyses demonstrated the formation of unusually long transparent tube-like structures which were enclosing separate single cells. The tube-like structures were isolated and analysed by SDS-PAGE, infrared-spectroscopy and different microscopic methods in order to identify their unusual composition and structure. The tube-like structures were found to be like outer membranes, containing high levels of proteins and to which the recombinant S-layer proteins were attached. Despite the entire structure being indicative of a disordered cell division, the bacterial cells were highly viable and stable. To our knowledge, this is the first time that the induction of drastic morphological changes in E. coli by the expression of a foreign protein has been reported.

scholarly journals Assessment Of Biologically Synthesized Ag Nanoparticles Toxicity Against E. coli, Staphylococcus aureus, Parachlorella kessleri And Sinapis alba

2015 ◽  
Vol 14 (1) ◽  
pp. 69-77 ◽  
Author(s):  
Jana Kaduková ◽  
Oksana Velgosová ◽  
Anna Mražíková ◽  
Renáta Marcinčáková ◽  
Eva Tkáčová
Keyword(s):  
Staphylococcus Aureus ◽  
Silver Nanoparticles ◽  
Seed Germination ◽  
Root Growth ◽  
Sinapis Alba ◽  
Bacterial Cells ◽  
Inhibitory Effects ◽  
Plant Seed ◽  
E Coli ◽  
Parachlorella Kessleri

Abstract In general, Ag+ ions and AgNPs are considered to be the most toxic for bacterial cells and less toxic for higher organisms. In the present work inhibitory effects of biologically prepared silver nanoparticles on the growth of bacteria E. coli CCM 3954 and Staphylococcus aureus CCM 3953, green microscopic alga Parachlorella kessleri LARG/1 and seed germination and root growth of plant Sinapis alba seeds were investigated. Surprisingly, silver nanoparticles showed much stronger inhibitory effects on plant seed germination and root growth than on the bacterial growth. At concentration of 75 mg/l AgNPs both seed germination and root growth of Sinapis alba was inhibited whereas inhibition of the growth of E. coli and S. aureus was observed at >195 mg/l. Growth inhibition of alga Parachlorella kessleri was recorded at 300 mg/l AgNPs concentration. The inhibitory effect of silver ions was much higher compared to silver nanoparticles. Even 20 mg/l concentration of Ag+ ions inhibited the root growth and concentration > 45 mg/l inhibited germination of Sinapis alba seeds. Inhibition zones in both studied bacteria were found at concentration > 140 mg/l.

scholarly journals Antibacterial and Antifungal Properties of Silver Nanoparticles—Effect of a Surface-Stabilizing Agent

Biomolecules ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1481
Author(s):  
Agnieszka Gibała ◽  
Paulina Żeliszewska ◽  
Tomasz Gosiewski ◽  
Agnieszka Krawczyk ◽  
Dorota Duraczyńska ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Epigallocatechin Gallate ◽  
Medical Application ◽  
Biologically Active ◽  
Bacterial Cells ◽  
Ion Release ◽  
Main Hypothesis ◽  
Stabilizing Agent ◽  
E Coli ◽  
Antibacterial And Antifungal

The biocidal properties of silver nanoparticles (AgNPs) prepared with the use of biologically active compounds seem to be especially significant for biological and medical application. Therefore, the aim of this research was to determine and compare the antibacterial and fungicidal properties of fifteen types of AgNPs. The main hypothesis was that the biological activity of AgNPs characterized by comparable size distributions, shapes, and ion release profiles is dependent on the properties of stabilizing agent molecules adsorbed on their surfaces. Escherichia coli and Staphylococcus aureus were selected as models of two types of bacterial cells. Candida albicans was selected for the research as a representative type of eukaryotic microorganism. The conducted studies reveal that larger AgNPs can be more biocidal than smaller ones. It was found that positively charged arginine-stabilized AgNPs (ARGSBAgNPs) were the most biocidal among all studied nanoparticles. The strongest fungicidal properties were detected for negatively charged EGCGAgNPs obtained using (−)-epigallocatechin gallate (EGCG). It was concluded that, by applying a specific stabilizing agent, one can tune the selectivity of AgNP toxicity towards desired pathogens. It was established that E. coli was more sensitive to AgNP exposure than S. aureus regardless of AgNP size and surface properties.

scholarly journals Study of Antibacterial Efficacy of Hybrid Chitosan-Silver Nanoparticles for Prevention of Specific Biofilm and Water Purification

2011 ◽  
Vol 2011 ◽  
pp. 1-11 ◽  
Author(s):  
Somnath Ghosh ◽  
Tasneem Kausar Ranebennur ◽  
H. N. Vasan
Keyword(s):  
Silver Nanoparticles ◽  
Hybrid Film ◽  
Saline Solution ◽  
Morphological Changes ◽  
Steel Strip ◽  
Antibacterial Properties ◽  
Layer By Layer ◽  
Antibacterial Efficacy ◽  
Ag Nps ◽  
E Coli

Antibacterial efficacy of silver nanoparticles (Ag NPs) deposited alternatively layer by layer (LBL) on chitosan polymer in the form of a thin film over a quartz plate and stainless steel strip has been studied. An eight-bilayer chitosan/silver (Cs/Ag)8 hybrid was prepared having a known concentration of silver. Techniques such as UV-visible spectroscopy, inductively coupled plasma optical emission spectroscopy (ICP-OES), and atomic force microscopy (AFM) were carried out to understand and elucidate the physical nature of the film. Gram-negative bacteria, Escherichia coli (E. coli), were used as a test sample in saline solution for antibacterial studies. The growth inhibition at different intervals of contact time and, more importantly, the antibacterial properties of the hybrid film on repeated cycling in saline solution have been demonstrated. AFM studies are carried out for the first time on the microbe to know the morphological changes affected by the hybrid film. The hybrid films on aging (3 months) are found to be as bioactive as before. Cytotoxicity experiments indicated good biocompatibility. The hybrid can be a promising bioactive material for the prevention of biofilms specific to E. coli and in purification of water for safe drinking.

scholarly journals Silver Nanoparticles Enhance Antimicrobial Efficacy of Antibiotics and Restore That Efficacy against the Melioidosis Pathogen

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 839
Author(s):  
Sathit Malawong ◽  
Saengrawee Thammawithan ◽  
Pawinee Sirithongsuk ◽  
Sakda Daduang ◽  
Sompong Klaynongsruang ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Burkholderia Pseudomallei ◽  
Inhibitory Concentration ◽  
Morphological Changes ◽  
Bacterial Cells ◽  
Bacterial Strains ◽  
Antibacterial Effects ◽  
Negative Bacillus ◽  
Conventional Antibiotics ◽  
Potential Therapeutics

Melioidosis is an infectious disease caused by Gram-negative bacillus bacteria Burkholderia pseudomallei. Due to the emerging resistance of B. pseudomallei to antibiotics including ceftazidime (CAZ), the development of novel antibiotics and alternative modes of treatment has become an urgent issue. Here, we demonstrated an ability to synergistically increase the efficiency of antibiotics through their combination with silver nanoparticles (AgNPs). Combinations of four conventional antibiotics including CAZ, imipenem (IMI), meropenem (MER), and gentamicin sulfate (GENT) with starch-stabilized AgNPs were tested for their antibacterial effects against three isolates of B. pseudomallei. The combination of each antibiotic with AgNPs featured fractional inhibitory concentration (FIC) index values and fractional bactericidal concentration (FBC) index values ranging from 0.312 to 0.75 µg/mL and 0.252 to 0.625 µg/mL, respectively, against the three isolates of B. pseudomallei. The study clearly showed that most of the combinatorial treatments exhibited synergistic antimicrobial effects against all three isolates of B. pseudomallei. The highest enhancing effect was observed for GENT with AgNPs. These results confirmed the combination of each antibiotic with AgNPs restored their bactericidal potency in the bacterial strains that had previously been shown to be resistant to the antibiotics. In addition, morphological changes examined by SEM confirmed that the bacterial cells were severely damaged by combinations at the FBC level. Although bacteria produce fibers to protect themselves, ultimately the bacteria were killed by the antibiotic–AgNPs combinations. Overall, these results suggest the study of antibiotic–AgNPs combinations as an alternative design strategy for potential therapeutics to more effectively combat the melioidosis pathogen.

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. 

Antimicrobial Activity of Silver Nanoparticles Synthesized by Streptomyces Species JF714876

2012 ◽  
Vol 5 (1) ◽  
pp. 1638-1642 ◽  
Author(s):  
Vidyasagar G M ◽  
Shankaravva B ◽  
R Begum ◽  
Imrose ◽  
Sagar R ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Silver Ions ◽  
Human Beings ◽  
Streptomyces Species ◽  
Force Microscopy ◽  
E Coli ◽  
Extracellular Synthesis ◽  
Atomic Force ◽  
Uv Visible

Microorganisms like fungi, actinomycetes and bacteria are considered nanofactories and are helpful in the production of nanoparticles useful in the welfare of human beings. In the present study, we investigated the production of silver nanoparticles from Streptomyces species JF714876. Extracellular synthesis of silver nanoparticles by Streptomyces species was carried out using two different media. Silver nanoparticles were examined using UV-visible, IR and atomic force microscopy. The size of silver nanoparticles was in the range of 80-100 nm. Antimicrobial activity of silver nanoparticle against bacteria such as E. coli, S. aureus, and dermatophytes like T. rubrum and T. tonsurans was determined. Thus, this study suggests that the Streptomyces sp. JF741876 can produce silver ions that can be used as an antimicrobial substance.

Efficacy of Silver Nanoparticles Synthesized from Hymenocallis species (Spider Lilly) Leaf Extract as Antimicrobial Agents

2019 ◽  
Vol 12 (5) ◽  
pp. 4644-4647
Author(s):  
K.K. Gupta ◽  
Neha Kumari ◽  
Neha Sinha ◽  
Akruti Gupta
Keyword(s):  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Antimicrobial Agents ◽  
Color Change ◽  
Bacterial Species ◽  
Antimicrobial Property ◽  
Biogenic Synthesis ◽  
E Coli ◽  
Light Yellow ◽  
Antibiotic Property

Biogenic synthesis of silver nanoparticles synthesized from Hymenocallis species (Spider Lilly) leaf extract was subjected for investigation of its antimicrobial property against four bacterial species (E. coli, Salmonella sp., Streptococcus sp. & Staphylococcus sp.). The results revealed that synthesized nanoparticles solution very much justify the color change property from initial light yellow to final reddish brown during the synthesis producing a characteristics absorption peak in the range of 434-466 nm. As antimicrobial agents, their efficacy was evaluated by analysis of variance in between the species and among the different concentration of AgNPs solution, which clearly showed that there was significant variation in the antibiotic property between the four different concentrations of AgNPs solution and also among four different species of bacteria taken under studies. However, silver nanoparticles solution of 1: 9 and 1:4 were proved comparatively more efficient as antimicrobial agents against four species of bacteria.

Toxic Effect of 2-ethyl (bicyclo[2.2.1] heptane) on Bacterial Cells

2019 ◽  
Vol 35 (6) ◽  
pp. 67-72 ◽  
Author(s):  
I.V. Manukhov ◽  
L.S. Yaguzhinsky ◽  
M.V. Bermeshev ◽  
M.A. Zisman ◽  
V.G. Pevgov ◽  
...  
Keyword(s):  
Toxic Effect ◽  
Atmospheric Oxygen ◽  
Inducible Promoter ◽  
Oxygen Species ◽  
Bacterial Cells ◽  
Unique Identifier ◽  
E Coli ◽  
Lux Biosensors ◽  
High Level ◽  
Ministry Of Higher Education

Toxic effect of 2-ethylnorbornane (2-ethyl(bicyclo[2.2.1]heptane) (EBH)) on bacteria has been studied using the E. coli pRecA-lux and E. coli pKatG- lux cells as lux-biosensors. It was shown that the addition of EBH to the incubation medium leads to death and growth retardation, high level oxidative stress and DNA damage in E. coli cells. It is assumed that the oxidation of EBH with atmospheric oxygen causes the formation of reactive oxygen species in the medium, which makes a major contribution to the toxicity of this substance. biosensor, luciferase, bioluminescence, inducible promoter, PrecA, PkatG The authors are grateful to Stanislav Filippovich Chalkin for the development of interdisciplinary ties in the scientific community. The work was financially supported by the Ministry of Higher Education and Science of Russia (Project Unique Identifier RFMEFI60417X0181, Agreement No. 14.604.21.0181 of 26.09.2017).

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