Journal: Journal of Applied Polymer Science

Article Title: Antibacterial and cytotoxic performance of methenamine‐based poly(lactic acid)/poly(ethylene glycol) (PLA/PEG) composite films

doi: 10.1002/app.55412

Figure Lengend Snippet: FIGURE 6 Antimicrobial activity results of PLA, PLA/PEG, and PLA/PEG/MA films against (a) Escherichia coli (E. coli) and (b) Staphylococcus aureus (S. aureus). PEG, poly(ethylene glycol); PLA, poly(lactic acid); MA, methenamine. [Color figure can be viewed at wileyonlinelibrary.com]

Article Snippet: The antimicrobial activity of PLA/PEG/MA films was examined by the contact-active method and was observed using two bacterial strains, gram-positive S. aureus ATCC 29213, and gram-negative E. coli ATCC 53323.

Techniques: Activity Assay

Journal: Journal of Applied Polymer Science

Article Title: Antibacterial and cytotoxic performance of methenamine‐based poly(lactic acid)/poly(ethylene glycol) (PLA/PEG) composite films

doi: 10.1002/app.55412

Figure Lengend Snippet: FIGURE 7 The results of antimicrobial activity of the PLA, PLA/PEG, and PLA/PEG/MA films on agar plates against (a) Escherichia coli and (b) Staphylococcus aureus. PEG, poly(ethylene glycol); PLA, poly(lactic acid); MA, methenamine. [Color figure can be viewed at wileyonlinelibrary.com]

Article Snippet: The antimicrobial activity of PLA/PEG/MA films was examined by the contact-active method and was observed using two bacterial strains, gram-positive S. aureus ATCC 29213, and gram-negative E. coli ATCC 53323.

Techniques: Activity Assay

Journal: BBA Advances

Article Title: Role of lipopolysaccharide in antimicrobial and cell penetrating peptide membrane interactions probed by deuterium NMR of whole cells

doi: 10.1016/j.bbadva.2022.100057

Figure Lengend Snippet: EDTA effects on lipid chain order, cell permeability and cell wall staining. A: 2H NMR spectra of deuterium-enriched E. coli that are untreated (black, SK-53); treated with 2.5 mM EDTA (blue, SK-38) and treated with 9 mM EDTA (red, SK-39) Dashed lines at ±12.5 kHz are included to facilitate the comparison of the spectra. Each spectrum is obtained from 110,000 scans recorded over 12 h at 37 °C in a 600 MHz NMR spectrometer and normalized by area. The top panel shows the overlaid spectra. Additional spectra obtained from samples with EDTA added are shown in Figs. S1 and S2. B: Cell count versus PI fluorescence intensity for E. coli cells treated with 2.5 mM and 9.0 mM EDTA as probed by flow cytometry with PI. The relatively small count numbers for high PI fluorescence intensity show that PI cannot penetrate 2.5 mM and 9.0 mM EDTA treated cells. C: Microscope images of cells treated with 9.0 mM EDTA and 2.5 mM EDTA after Gram staining. These show that 9.0 mM EDTA (but not 2.5 mM EDTA) treatment drastically changes bacterial shape and susceptibility to Gram staining. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article).

Article Snippet: Preparation of membrane deuterated E. coli JM109 (ATCC-68862) strain E. coli bacteria were grown with a PA -d 31 -DPC mixture incorporated in the growth medium as described before [45] and outlined below.

Techniques: Permeability, Staining, Comparison, Cell Counting, Fluorescence, Flow Cytometry, Microscopy

Journal: BBA Advances

Article Title: Role of lipopolysaccharide in antimicrobial and cell penetrating peptide membrane interactions probed by deuterium NMR of whole cells

doi: 10.1016/j.bbadva.2022.100057

Figure Lengend Snippet: CPP peptide increases the amplitude of lipid chain motions but does not induce membrane permeabilization. A: 2H NMR spectra of deuterium-enriched E. coli that are untreated (black, SK-53); after treatment with 30 % TP2 (pink, SK-71); and after treatment with 30 % MSI-78 (purple, SK-55) B:2H NMR spectra of deuterium-enriched E. coli that are untreated (black, SK-53); after treatment with 30 % TP2 (pink, SK-71) and after treatment with 9 mM EDTA followed by 30 % TP2 (orange, SK-72). Dashed lines at ±12.5 kHz are shown to facilitate the comparison of the spectra. Each spectrum is obtained from 110,000 scans recorded over 12 h at 37 °C in a 600 MHz NMR spectrometer and normalized by area. Only selected spectra are shown; additional spectra are shown in Fig. S6. C: Flow cytometry cell count vs. PI fluorescence intensity for E. coli cells treated with 30 % TP2 and 9.0 mM EDTA+TP2. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article).

Article Snippet: Preparation of membrane deuterated E. coli JM109 (ATCC-68862) strain E. coli bacteria were grown with a PA -d 31 -DPC mixture incorporated in the growth medium as described before [45] and outlined below.

Techniques: Membrane, Comparison, Flow Cytometry, Cell Counting, Fluorescence

Journal: BBA Advances

Article Title: Role of lipopolysaccharide in antimicrobial and cell penetrating peptide membrane interactions probed by deuterium NMR of whole cells

doi: 10.1016/j.bbadva.2022.100057

Figure Lengend Snippet: 2H NMR spectra of membrane-deuterated E. coli are reproducible. Shown are spectra from 3 independent preparations of bacteria (purple, SK-53; red, SK-37; green, SK-31). Dashed lines at ±12.5 kHz are included to facilitate the comparison of the spectra. Each spectrum is obtained from 110,000 scans recorded over 12 h at 37°C in a 600 MHz NMR spectrometer and normalized by area. The high degree of overlap in the stacked spectra on top shows that the spectra are reproducible. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article).

Article Snippet: Preparation of membrane deuterated E. coli JM109 (ATCC-68862) strain E. coli bacteria were grown with a PA -d 31 -DPC mixture incorporated in the growth medium as described before [45] and outlined below.

Techniques: Membrane, Bacteria, Comparison

Journal: BBA Advances

Article Title: Role of lipopolysaccharide in antimicrobial and cell penetrating peptide membrane interactions probed by deuterium NMR of whole cells

doi: 10.1016/j.bbadva.2022.100057

Figure Lengend Snippet: LPS pre-treatment increases the susceptibility of bacteria to AMP as judged by 2H NMR and flow cytometry. A: 2H NMR spectra of deuterium-enriched E. coli that are untreated (black, SK-53); after treatment with 30 % MSI-78 (green, SK-47) (% by dry weight of bacteria), and after treatment with 9 mM EDTA followed by 30 % MSI-78 (purple, SK-55). The top panel shows the overlaid spectra. Dashed lines at ∼±12.5 kHz are shown to facilitate the comparison of the spectra. The inset showing overlaid spectra is included to better show spectral changes around the center of the spectra. Each spectrum is obtained from 110,000 scans recorded over 12 h at 37 °C in a 600 MHz NMR spectrometer and normalized by area. Only selected spectra are shown. Additional spectra are shown in Figs S4 and S5. B: Cell count vs. PI fluorescence intensity for treated E. coli cells treated with 30 % MSI-78 alone and 9.0 mM EDTA + MSI-78, as probed by flow cytometry with PI. Peptide amounts are given as a % weight by dry weight of bacteria to facilitate calculation of AMP: lipid ratios and allow comparisons with other types of AMP studies [41].

Article Snippet: Preparation of membrane deuterated E. coli JM109 (ATCC-68862) strain E. coli bacteria were grown with a PA -d 31 -DPC mixture incorporated in the growth medium as described before [45] and outlined below.

Techniques: Bacteria, Flow Cytometry, Comparison, Cell Counting, Fluorescence

Journal: FEMS microbiology letters

Article Title: Identification of an antibacterial protein by functional screening of a human oral metagenomic library.

doi: 10.1093/femsle/fnv142

Figure Lengend Snippet: Figure 2. Activity screening of p112C subclones in pTGEX vector expressed in E. coli DH5α. The vector alone negative control and the 7 and 3.9 kb subclones did not show antagonistic activity against the overlaid B. subtilis. However, the 4.7 kb subclone clearly showed a zone of growth inhibition.

Article Snippet: The indicator bacteria tested were as follows: Bacillus subtilis BS78H (a chloramphenicol resistant derivative of CU2189), Staphylococcus epidermidis NCTC 11964 and B4268, S. aureus NCTC 12493 NCTC 11561 and ATCC 35696, Pseudomonas aeruginosa ATCC 9027, Neisseria subflava ATCC A1078, Escherichia coli K12 JM109 and E. coli B BL21(DE3), Fusobacterium nucleatum ATCC 25586 and NCTC 11326, Prevotella intermedia ATCC 25611, Veillonella parvula ATCC 10790 and Lactobacillus casei NCTC 6375.

Techniques: Activity Assay, Plasmid Preparation, Negative Control, Inhibition