Characterizing the Impact of DAHP Synthase Mutations on Growth and Virulence in Pseudomonas aeruginosa Strain PAK
Faculty Mentor
Ben Lundgren
Presentation Type
Poster
Start Date
4-14-2026 2:00 PM
End Date
4-14-2026 4:00 PM
Location
PUB NCR
Primary Discipline of Presentation
Chemistry and Biochemistry
Abstract
Pseudomonas aeruginosa is a gram-negative opportunistic pathogen that causes infections ranging from mild rashes to severe pneumonia. The shikimate pathway synthesizes virulent aromatic metabolites to outcompete other microorganisms, with 3-deoxy-D-arabinoheptulosonate 7-phosphate (DAHP) synthase catalyzing the first step. We hypothesized that deletion of two DAHP synthase encoding genes would impair growth and metabolite production in P. aeruginosa strain PAK. To test this hypothesis, single and double knockout mutant strains were constructed. Growth assays, virulence metabolite production (pyoverdine and pyocyanin), and biofilm formation were evaluated in minimal and nutrient-rich media and compared with wild type (WT) PAK. Across multiple experiments, the mutant strains’ growth was significantly hindered while WT growth remained robust independent of conditions. Amino acid supplementation with phenylalanine, tyrosine, and tryptophan partially restored growth in the mutants. Mutants showed increased biofilm formation and altered pyoverdine and pyocyanin production. Disruption of DAHP synthase encoding genes impairs P. aeruginosa PAK viability in vitro. Accordingly, the shikimate pathway plays an important role in P. aeruginosa. These findings support aromatic amino acid biosynthesis as a potential antimicrobial target. The shikimate pathway is absent in humans, so it may be a target for antimicrobial drug development. Targeting DAHP synthase may help limit bacterial growth and virulence in P. aeruginosa infections. These studies provide a framework to genetically investigate toxin-related metabolic dependencies in clinically relevant infection models.
Recommended Citation
Simpson, Justin and Lough, Donovan, "Characterizing the Impact of DAHP Synthase Mutations on Growth and Virulence in Pseudomonas aeruginosa Strain PAK" (2026). 2026 Symposium. 15.
https://dc.ewu.edu/srcw_2026/ps_2026/p3_2026/15
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Characterizing the Impact of DAHP Synthase Mutations on Growth and Virulence in Pseudomonas aeruginosa Strain PAK
PUB NCR
Pseudomonas aeruginosa is a gram-negative opportunistic pathogen that causes infections ranging from mild rashes to severe pneumonia. The shikimate pathway synthesizes virulent aromatic metabolites to outcompete other microorganisms, with 3-deoxy-D-arabinoheptulosonate 7-phosphate (DAHP) synthase catalyzing the first step. We hypothesized that deletion of two DAHP synthase encoding genes would impair growth and metabolite production in P. aeruginosa strain PAK. To test this hypothesis, single and double knockout mutant strains were constructed. Growth assays, virulence metabolite production (pyoverdine and pyocyanin), and biofilm formation were evaluated in minimal and nutrient-rich media and compared with wild type (WT) PAK. Across multiple experiments, the mutant strains’ growth was significantly hindered while WT growth remained robust independent of conditions. Amino acid supplementation with phenylalanine, tyrosine, and tryptophan partially restored growth in the mutants. Mutants showed increased biofilm formation and altered pyoverdine and pyocyanin production. Disruption of DAHP synthase encoding genes impairs P. aeruginosa PAK viability in vitro. Accordingly, the shikimate pathway plays an important role in P. aeruginosa. These findings support aromatic amino acid biosynthesis as a potential antimicrobial target. The shikimate pathway is absent in humans, so it may be a target for antimicrobial drug development. Targeting DAHP synthase may help limit bacterial growth and virulence in P. aeruginosa infections. These studies provide a framework to genetically investigate toxin-related metabolic dependencies in clinically relevant infection models.
