Degree Name
MS (Master of Science)
Program
Biology
Date of Award
12-2026
Committee Chair or Co-Chairs
Sean J. Fox
Committee Members
Erik M. Petersen, Antonio E. Rusinol
Abstract
The global rise in antimicrobial resistance has catalyzed a greater focus on polymicrobial research aimed at characterizing microbial interactions and uncovering new therapeutic strategies. Though it has long been of interest, environmental soil-derived bacteria remain largely under-represented in research and thus uncharacterized in this field. This project aimed to identify soil microbes that display inhibitory mechanisms to potential nosocomial pathogens. Soil sample S1S3-2 displayed inhibitory phenotypes toward numerous bacteria and was identified as Pseudomonas baetica. In both planktonic and biofilm growth, P. baetica was able to inhibit Salmonella arizonae through a contact-dependent and temperature-dependent manner. Screening of a transposon insertion library of P. baetica against Salmonella revealed loss-of-function candidates linked to genes coding for Coniferyl Aldehyde Dehydrogenase, and methionine sulfide reductase. When utilized in a C. elegans in-vivo model, P. baetica was able to suppress the bacterial burden of Salmonella during coinfections. Taken collectively, this data demonstrates that P. baetica has a unique ability to inhibit the growth of Salmonella when in polymicrobial environments. Delineation of this mechanism could potentially be used as a suppressant to Salmonella or other foodborne bacteria.
Document Type
Thesis - unrestricted
Recommended Citation
Stout, Braxton E.M., "Exploring Competitive Dynamics Between Pseudomonas baetica and Salmonella in a Polymicrobial System" (2026). Electronic Theses and Dissertations. Paper 4766. https://dc.etsu.edu/etd/4766
Copyright
Copyright by the authors.
Included in
Bacteriology Commons, Environmental Microbiology and Microbial Ecology Commons, Molecular Genetics Commons
