Skip to main content

03.01.2019 | Original Article | Ausgabe 6/2019

Lasers in Medical Science 6/2019

Sub-lethal antimicrobial photodynamic inactivation: an in vitro study on quorum sensing-controlled gene expression of Pseudomonas aeruginosa biofilm formation

Lasers in Medical Science > Ausgabe 6/2019
Saghar Hendiani, Majid Pornour, Nasim Kashef


During antimicrobial photodynamic inactivation (APDI) in the treatment of an infection, it is likely that microorganisms would be exposed to sub-lethal doses of APDI (sAPDI). Although sAPDI cannot kill microorganisms, it can significantly affect microbial virulence. In this study, we evaluated the effect of sAPDI using methylene blue (MB) on the expression of genes belonging to two quorum sensing (QS) operons (rhl and las systems) and two genes necessary for biofilm formation (pelF and pslA) under QS control in Pseudomonas aeruginosa. Biofilm formation ability of P. aeruginosa ATCC 27853 exposed to sAPDI (MB at 0.012 mM and light dose of 23 J/cm2) was evaluated using triphenyl tetrazolium chloride (TTC) assay and scanning electron microscopy (SEM). The effect of sAPDI on expression of rhlI, rhlR, lasI, lasR, pelF, and pslA were also evaluated by quantitative real-time polymerase chain reaction. Quantitative assay (TTC) results and morphological observations (SEM) indicated that a single sAPDI treatment resulted in a significant decrease in biofilm formation ability of P. aeruginosa ATCC 27853 compared to their non-treated controls (P = 0.012). These results were consistent with the expression of genes belonging to rhl and las systems and pelF and pslA genes. The results suggested that the transcriptional decreases caused by MB-sAPDI did lead to phenotypic changes.

Bitte loggen Sie sich ein, um Zugang zu diesem Inhalt zu erhalten

e.Med Interdisziplinär

Für Ihren Erfolg in Klinik und Praxis - Die beste Hilfe in Ihrem Arbeitsalltag als Mediziner

Mit e.Med Interdisziplinär erhalten Sie Zugang zu allen CME-Fortbildungen und Fachzeitschriften auf

Weitere Produktempfehlungen anzeigen
Über diesen Artikel

Weitere Artikel der Ausgabe 6/2019

Lasers in Medical Science 6/2019 Zur Ausgabe
  1. Das kostenlose Testabonnement läuft nach 14 Tagen automatisch und formlos aus. Dieses Abonnement kann nur einmal getestet werden.