Journal: International Journal of Molecular Sciences

Article Title: Green Synthesis of Silver Nanoparticles with Antibacterial, Anti-Inflammatory, and Antioxidant Activity Using Convolvulus arvensis

doi: 10.3390/ijms27031210

Figure Lengend Snippet: Scanning Electron Microscopy (SEM) images showing the morphological effects of silver nanoparticles synthesized from C. arvensis. ( A – C ) demonstrate the effect on Gram-positive S. aureus (MRSA and ST), E-H demonstrate the effect on Gram-negative E. coli ESBL and ST) bacterial strains. described above, and the cells exhibited a division-related septum, broadening, and cytoplasm leakage. Scanning electron microscope images showed that the untreated control groups ( A , C , E , G ), bacterial cells exhibited normal morphology with intact cell walls and smooth surfaces. In contrast, treated cells ( B , D , F , H ) showed significant morphological changes: S. aureus cells displayed shrinkage and deformations in their spherical shape, while E. coli cells exhibited marked structural disintegration and severe membrane damage. These observations confirm the destructive effects of silver nanoparticles on bacterial cell integrity. Most of the cells were damaged and perforated, which changed the cell structure and shape, and it was noted that some of them were empty. In addition, most cells appeared to stick together compared to untreated cells. As is clear in .

Article Snippet: Four bacterial strains were used in this study: one standard Gram-positive strain ( Staphylococcus aureus ATCC 29213 ), one standard Gram-negative strain ( Escherichia coli ATCC 25922 ), and two clinical isolates (SP1 and SP2) obtained from patient samples.

Techniques: Electron Microscopy, Synthesized, Microscopy, Control, Membrane

Journal: Frontiers in Microbiology

Article Title: The antibacterial activity of a photoactivatable diarylacetylene against Gram-positive bacteria

doi: 10.3389/fmicb.2023.1243818

Figure Lengend Snippet: Screening lead compounds for antibacterial activity against Gram-positive and Gram-negative bacteria. Two-fold dilutions of six lead compounds (labelled 1–6) were applied in 6 μL volumes to the surface of a soft agar overlay inoculated with Bacillus subtilis , Staphylococcus epidermidis , Escherichia coli or Pseudomonas fluorescens . The LB agar plates were exposed to light at 365 nm for 5 min and then incubated for 24 h at 37°C prior to imaging. Controls without light activation or with application of DMSO are shown in .

Article Snippet: Bacillus subtilis 168 (ATCC 23857), Staphylococcus epidermidis (ATCC 12228), Pseudomonas fluorescens (ATCC 13525) and Escherichia coli FDA strain Seattle 1946 (ATCC 25922) were obtained from the American Type Culture Collection.

Techniques: Activity Assay, Bacteria, Incubation, Imaging, Activation Assay

Journal: Frontiers in Microbiology

Article Title: The antibacterial activity of a photoactivatable diarylacetylene against Gram-positive bacteria

doi: 10.3389/fmicb.2023.1243818

Figure Lengend Snippet: Effect of Compound 2 on bacterial growth. Escherichia coli (A) , B. subtilis (B) and S. epidermidis (C) were cultivated in LB broth at 37°C in 96-well plates in a plate reader with continuous shaking. Growth was monitored at OD 600nm in samples exposed to light at 365 nm for 5 min (filled symbols) or without light treatment (open symbols). Samples contained 2 μM Compound 2 or 0.2% DMSO indicated by circles or squares, respectively.

Article Snippet: Bacillus subtilis 168 (ATCC 23857), Staphylococcus epidermidis (ATCC 12228), Pseudomonas fluorescens (ATCC 13525) and Escherichia coli FDA strain Seattle 1946 (ATCC 25922) were obtained from the American Type Culture Collection.

Techniques:

Journal: Frontiers in Microbiology

Article Title: The antibacterial activity of a photoactivatable diarylacetylene against Gram-positive bacteria

doi: 10.3389/fmicb.2023.1243818

Figure Lengend Snippet: Real-time monitoring of bacterial membrane integrity. The BacLight assay of membrane integrity following photoactivation of Compound 2 . S. epidermidis (A) , B. subtilis (B) , P. fluorescens (C) and E. coli (D) in mid-log phase of growth were stained with PI (magenta) and SYTO 9 (yellow) and imaged by confocal microscopy without light activation (−) or 10 min after photoactivation with the 405 nm laser (+). The laser was applied at 30% power for 1 min. The bar represents 3 μm.

Article Snippet: Bacillus subtilis 168 (ATCC 23857), Staphylococcus epidermidis (ATCC 12228), Pseudomonas fluorescens (ATCC 13525) and Escherichia coli FDA strain Seattle 1946 (ATCC 25922) were obtained from the American Type Culture Collection.

Techniques: Membrane, BacLight Assay, Staining, Confocal Microscopy, Activation Assay

Journal: Frontiers in Microbiology

Article Title: The antibacterial activity of a photoactivatable diarylacetylene against Gram-positive bacteria

doi: 10.3389/fmicb.2023.1243818

Figure Lengend Snippet: Role of the E. coli outer membrane in protecting against Compound 2 toxicity. (A) The viability of E. coli O + , O − and Δ rfaC cells was evaluated as in with exposure to 2 μM Compound 2 with or without light activation. (B) PI assay of E. coli strains to monitor loss of membrane integrity. (C) Real-time imaging of E. coli strains stained with PI (magenta) and SYTO 9 (yellow) by confocal microscopy. Images taken prior to light exposure (−) and 10 min after photoactivation (+) as indicated. The bar represents 3 μm.

Article Snippet: Bacillus subtilis 168 (ATCC 23857), Staphylococcus epidermidis (ATCC 12228), Pseudomonas fluorescens (ATCC 13525) and Escherichia coli FDA strain Seattle 1946 (ATCC 25922) were obtained from the American Type Culture Collection.

Techniques: Membrane, Activation Assay, Imaging, Staining, Confocal Microscopy

Journal: Frontiers in Microbiology

Article Title: The antibacterial activity of a photoactivatable diarylacetylene against Gram-positive bacteria

doi: 10.3389/fmicb.2023.1243818

Figure Lengend Snippet: Susceptibility of E. coli strains deficient in oxidative damage and tolerance pathways. The viability of bacteria exposed to 2 μM Compound 2 after photoactivation is shown. Serial dilutions of bacteria were applied to LB agar plates and colonies counted to determine CFU/ml. A representative image of each strain is shown (A) and the CFU/ml (B) represents the mean and standard error of three independent experiments.

Article Snippet: Bacillus subtilis 168 (ATCC 23857), Staphylococcus epidermidis (ATCC 12228), Pseudomonas fluorescens (ATCC 13525) and Escherichia coli FDA strain Seattle 1946 (ATCC 25922) were obtained from the American Type Culture Collection.

Techniques: Bacteria