Journal: Virulence

Article Title: Colistin-induced transition from non-mucoid to mucoid phenotype in resistant Pseudomonas aeruginosa ST3351

doi: 10.1080/21505594.2025.2580097

Figure Lengend Snippet: Psa -ST3351(+CST) incorporates L-Ara4N into its lipid a structure. The lipid a structure of Psa -ST3351 was determined by MALDI-TOF mass spectrometry. (A) Lipid a spectra from Psa -ST3351 and Psa -ST3351(+CST) were obtained by negative-ion reflection MALDI-TOF mass spectrometry. Red arrows highlight L-Ara4N addition. (B) Predicted lipid a structures of Psa -ST3351 with and without modifications. m/z 1445 , penta-acylated lipid a; m/z 1576 and m/z 1747 , L-Ara4N modification (in red) to penta- and hexa-acylated forms, respectively. Hexa-acylation is indicated in blue.

Article Snippet: At a dose of 10 7 CFU, 60% infected mice with Psa -ST3351 reached the humane endpoint at 48 h p.i. , while all infected mice with Psa -ST3351 (+CST) had to be sacrificed at this time , while at a dose of 10 8 CFU, all mice infected with either Psa -ST3351 or Psa -ST3351 (+CST) had to be culled at 24 h ( ).

Techniques: Mass Spectrometry, Modification

Journal: Virulence

Article Title: Colistin-induced transition from non-mucoid to mucoid phenotype in resistant Pseudomonas aeruginosa ST3351

doi: 10.1080/21505594.2025.2580097

Figure Lengend Snippet: CST induces a transition from non-mucoid to a mucoid phenotype in Psa -ST3351. (A) Psa -ST3351 and Psa -ST3351(+CST) strains were grown on cetrimide agar plates for 24 h at 37 ° C and then at room temperature for an additional 24 h. The production of (B) pyoverdine and (c) pyocyanin was quantified and normalized at OD 600 . (D) Biofilm production on polystyrene surfaces, and (E) swarming motility was assessed on lb plates with 0.95 % (w/v) nutrient agar and quantified. Results represent the average of three biological repeats, performed in duplicate. Significant differences were obtained by a paired t-test. *, p < 0.05; ***, p < 0.0001; ****, p < 0.00001.

Article Snippet: At a dose of 10 7 CFU, 60% infected mice with Psa -ST3351 reached the humane endpoint at 48 h p.i. , while all infected mice with Psa -ST3351 (+CST) had to be sacrificed at this time , while at a dose of 10 8 CFU, all mice infected with either Psa -ST3351 or Psa -ST3351 (+CST) had to be culled at 24 h ( ).

Techniques:

Journal: Virulence

Article Title: Colistin-induced transition from non-mucoid to mucoid phenotype in resistant Pseudomonas aeruginosa ST3351

doi: 10.1080/21505594.2025.2580097

Figure Lengend Snippet: CST inhibits ExoS release via the T3SS and enhances bacterial competition in Psa -ST3351. (A) Psa -ST3351 was grown to early stationary phase under T3SS-inducing conditions either without (-) or with (+) CST. ExoS and GroEL were detected in filtered bacterial supernatants by Western blotting. PAO1 and ATCC 9027 (a strain lacking the T3SS) were used as positive and negative controls, respectively. Protein mass was estimated using the precision plus Protein dual color standard. ExoS and GroEL are indicated with arrows. (B) In competition assays, Escherichia coli DH10B (prey) was incubated with Psa- ST3351 (predator) in the absence (-) or presence (+) of CST at prey-to-predator ratios of 1:1 or 2:1. Results represent the average of three biological repeats, performed in duplicate. The graphs show the Fold change in CFUs recovered relative to the input. As a control, heat-killed (red bar) Psa -ST3351 exposed to CST was used at a 2:1 ratio. One-way anova with Tukey’s test for multiple comparisons was performed. ns, non-significant; ****, p < 0.00001.

Article Snippet: At a dose of 10 7 CFU, 60% infected mice with Psa -ST3351 reached the humane endpoint at 48 h p.i. , while all infected mice with Psa -ST3351 (+CST) had to be sacrificed at this time , while at a dose of 10 8 CFU, all mice infected with either Psa -ST3351 or Psa -ST3351 (+CST) had to be culled at 24 h ( ).

Techniques: Western Blot, Incubation, Control

Journal: Virulence

Article Title: Colistin-induced transition from non-mucoid to mucoid phenotype in resistant Pseudomonas aeruginosa ST3351

doi: 10.1080/21505594.2025.2580097

Figure Lengend Snippet: Reduced cell adhesion and internalization of Psa -ST3351(+CST) by macrophages. Monolayers of human THP1-monocytes differentiated to macrophages were infected with Psa -ST3351 with (+) or without (-) CST at an moi of 50 for 30 min. (A) CFUs were quantified to assess adherence, (B) phagocytosis, (C) bacterial survival, and (D) cytotoxicity. Results represent the average of three biological repeats, performed in duplicate. Significant differences were obtained using a paired t-test. ns, non-significant; ****, p < 0.00001.

Article Snippet: At a dose of 10 7 CFU, 60% infected mice with Psa -ST3351 reached the humane endpoint at 48 h p.i. , while all infected mice with Psa -ST3351 (+CST) had to be sacrificed at this time , while at a dose of 10 8 CFU, all mice infected with either Psa -ST3351 or Psa -ST3351 (+CST) had to be culled at 24 h ( ).

Techniques: Infection

Journal: Virulence

Article Title: Colistin-induced transition from non-mucoid to mucoid phenotype in resistant Pseudomonas aeruginosa ST3351

doi: 10.1080/21505594.2025.2580097

Figure Lengend Snippet: Macrophages infected with Psa- ST3351 and Psa -ST3351(+CST) release proinflammatory cytokines. Monolayers of human THP1-monocytes differentiated to macrophages were infected with Psa -ST3351 with (+) or without (-) CST at an moi of 50 for 30 min. At 24 h p.I. supernatants were collected for the quantification of (A) TNFα, (B) IL-1β, (C) IL-17A, (D) IL-8, (E) IL-13, and (F) IL-22 by elisa. Results represent the average of three biological repeats, performed in duplicate. ni, non-infected. Significant differences were obtained using a paired t-test. ns, non-significant; *, p < 0.05; **, p < 0.01.

Article Snippet: At a dose of 10 7 CFU, 60% infected mice with Psa -ST3351 reached the humane endpoint at 48 h p.i. , while all infected mice with Psa -ST3351 (+CST) had to be sacrificed at this time , while at a dose of 10 8 CFU, all mice infected with either Psa -ST3351 or Psa -ST3351 (+CST) had to be culled at 24 h ( ).

Techniques: Infection, Enzyme-linked Immunosorbent Assay

Journal: Virulence

Article Title: Colistin-induced transition from non-mucoid to mucoid phenotype in resistant Pseudomonas aeruginosa ST3351

doi: 10.1080/21505594.2025.2580097

Figure Lengend Snippet: Pathogenicity of Psa -ST3351(+CST) in a mouse pneumonia model. Seven groups of BALB/c mice (five mice per cage) were used. One group was intranasally mock-infected with saline solution. In contrast, the remaining groups were intranasally infected with 10 6 (continuous line), 10 7 (dotted line), or 10 8 (dashed line) CFUs of either (A) Psa -ST3351 or (B) Psa -ST3351(+CST) per mouse. Kaplan-meier graphs were created with graph prism 9.0, showing the data from two independent experiments. (C) lungs from uninfected and infected mice (24 hours post-infection) with Psa -ST3351 or Psa -ST3351(+CST) were processed and stained with H&E. Representative images of mice treated with pbs and infected with Psa -ST3351 or Psa -ST3351(+CST) are shown. Images were taken with a 60x objective; arrows indicate the presence of neutrophils, and arrowheads indicate the presence of monocytes. Bars indicate 20 μm. br, bronchiole. The quantification of neutrophils in peribronchial areas was from five aleatory images from three animals ( n = 15). A significant difference was obtained by a paired t-test. *, p < 0.05.

Article Snippet: At a dose of 10 7 CFU, 60% infected mice with Psa -ST3351 reached the humane endpoint at 48 h p.i. , while all infected mice with Psa -ST3351 (+CST) had to be sacrificed at this time , while at a dose of 10 8 CFU, all mice infected with either Psa -ST3351 or Psa -ST3351 (+CST) had to be culled at 24 h ( ).

Techniques: Infection, Saline, Staining

Journal: bioRxiv

Article Title: LSD1 inhibitors induce neuronal differentiation of Merkel cell carcinoma by disrupting the LSD1-CoREST complex and activating TGFβ signaling

doi: 10.1101/2020.04.14.041657

Figure Lengend Snippet: a , Bulk mouse skin labeled with IgM-PE mouse isotype control. b , Bulk mouse skin labeled with NCAM-PE. DAPI - cells were sorted. c , Merkel cells labeled with IgM-PE mouse isotype control. d , Merkel cells labeled with NCAM-PE. DAPI - /NCAM + cells were sorted. Each plot shows the subpopulation gated for in the preceding plot to the left.

Article Snippet: Merkel cells were stained with anti-PSA-NCAM-PE antibody (Miltenyi Biotec, Cat. 130-117-394) or with mouse IgM-PE isotype control (Miltenyi Biotec, Cat. 130-120-070) according to manufacturer’s instructions, for 10 min at 4°C.

Techniques: Labeling, Control