Sub-lethal antimicrobial photodynamic inactivation affects Pseudomonas aeruginosa PAO1 quorum sensing and cyclic di-GMP regulatory systems
| Autor: | Tim Tolker-Nielsen, Morten Rybtke, Nasim Kashef, Saghar Hendiani |
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| Rok vydání: | 2019 |
| Předmět: |
Cyclic di-GMP
Virulence Factors Biophysics Dermatology Real-Time Polymerase Chain Reaction medicine.disease_cause Virulence factor Microbiology chemistry.chemical_compound Pyocyanin medicine Pharmacology (medical) Cyclic GMP Photosensitizing Agents Pyoverdine biology Pseudomonas aeruginosa Biofilm Quorum Sensing Gene Expression Regulation Bacterial biology.organism_classification Methylene Blue Quorum sensing Photochemotherapy Oncology chemistry Genes Bacterial Biofilms Bacteria |
| Zdroj: | Photodiagnosis and Photodynamic Therapy. 27:467-473 |
| ISSN: | 1572-1000 |
| DOI: | 10.1016/j.pdpdt.2019.07.025 |
| Popis: | Background Antimicrobial photodynamic inactivation (APDI) is a new therapeutic modality which needs more precision during application due to the possibility of exposure of bacteria to sub-lethal doses (sAPDI). In this study, we aimed to evaluate the effect of sAPDI on Pseudomonas aeruginosa quorum sensing (QS) and c-di-GMP signaling which are important virulence factor regulatory systems. Methods Biofilm formation, pyoverdine, pyocyanin and protease production of P. aeruginosa was evaluated before and after a single sAPDI treatment with 0.8 mM methylene blue (MB) plus 1, 2, and 5-min irradiation with red laser light. Fluorescent lasB, rhlA, pqsA, and cdrA reporters of P. aeruginosa PAO1 and P. aeruginosa ΔmexAB-oprM were treated individually with sAPDI and the regulatory signals were detected. The gene expressions were also assessed after sAPDI using quantitative real-time PCR analysis. Results Morphological observations and molecular assessments indicated that sAPDI with 0.8 mM MB along with 2- and 5-min irradiation led to an increase in the expression of the Las QS system and c-di-GMP signaling, while 1 min irradiation revealed dissimilar results (increase in lasB expression and decrease in c-di-GMP levels). Expression of rhlA and pqsA did not change in response to sAPDI. Further, a severe lethal effect of sAPDI was observed in P. aeruginosa ΔmexAB-oprM as compared with the wild type strain, whilst there was no difference in QS and c-di-GMP levels as detected by reporters between treated and untreated samples. Conclusion The results suggest that sAPDI affects QS and c-di-GMP signaling inP. aeruginosa in a time-dependent manner. |
| Databáze: | OpenAIRE |
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