Effect of exoU vs exoS genes in Pseudomonas aeruginosa bloodstream isolateson Galleria mellonella

Session Number

Project ID: MEDH 27

Advisor(s)

Dr. Alan Hauser; Northwestern Feinberg School of Medicine

Discipline

Medical and Health Sciences

Start Date

22-4-2020 10:25 AM

End Date

22-4-2020 10:40 AM

Abstract

Pseudomonas aeruginosa is a highly antibiotic-resistant bacteria causing hospital-acquired infections. It utilizes a Type 3 Secretion System and four effector proteins (ExoS, ExoT, ExoU, and ExoY) to carry out its infections. Past studies in mice have shown that ExoU strains are the most harmful causing immediate cell lysis. However, almost all studies researching P. aeruginosa have been conducted using the lengthy and expensive mouse model. Recently, researchers are looking to the cheaper, easier, and quicker Galleria mellonella model as an alternative. This study analyzed the effects of the exoU gene versus the exoS gene being present in P. aeruginosa on the survival of G. mellonella. Larvae between 250-350mg were injected with three different dilutions (10 larvae per dilution) of each P. aeruginosa strain and were scored after 18 hours of incubation. This process was repeated for 96 strains of P. aeruginosa and strains were binned based on high, medium, and low virulence. The results of this research reject the hypothesis, with the exoS gene being more virulent than the exoU gene in G. mellonella. These results are contrary to past studies on mice, therefore suggesting that the Galleria model requires further research to effectively replace the mouse model.

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Apr 22nd, 10:25 AM Apr 22nd, 10:40 AM

Effect of exoU vs exoS genes in Pseudomonas aeruginosa bloodstream isolateson Galleria mellonella

Pseudomonas aeruginosa is a highly antibiotic-resistant bacteria causing hospital-acquired infections. It utilizes a Type 3 Secretion System and four effector proteins (ExoS, ExoT, ExoU, and ExoY) to carry out its infections. Past studies in mice have shown that ExoU strains are the most harmful causing immediate cell lysis. However, almost all studies researching P. aeruginosa have been conducted using the lengthy and expensive mouse model. Recently, researchers are looking to the cheaper, easier, and quicker Galleria mellonella model as an alternative. This study analyzed the effects of the exoU gene versus the exoS gene being present in P. aeruginosa on the survival of G. mellonella. Larvae between 250-350mg were injected with three different dilutions (10 larvae per dilution) of each P. aeruginosa strain and were scored after 18 hours of incubation. This process was repeated for 96 strains of P. aeruginosa and strains were binned based on high, medium, and low virulence. The results of this research reject the hypothesis, with the exoS gene being more virulent than the exoU gene in G. mellonella. These results are contrary to past studies on mice, therefore suggesting that the Galleria model requires further research to effectively replace the mouse model.