Priscilla Barger, PhD

Education

B.S., Auburn University
M.S., University of West Georgia
Ph.D., Auburn University

Biography

Dr. Barger was introduced to the magical world of microbes as an undergraduate at Auburn University.  Her research journey began in the Bacterial Physiology lab of Dr. Tom Pitta, where she studied gliding motility and virulence in the fish pathogen Flavobacterium columnare. This early exposure to aquatic pathogens led to a position as a research assistant in a fish health lab at the USDA-ARS Catfish Genetics Research Unit, where she gained hands-on experience in catfish husbandry and developed a deep appreciation for the complex interplay between aquatic ecosystems and animal health. This interest in aquatic ecology guided her master’s thesis, which focused on the population structure of Oscillatoria agardhii, a hypolimnetic cyanobacterium that produces a toxic metabolite affecting the taste of pond-raised and wild fish, as well as drinking water. This research further fueled her fascination with environmental microbiology and the complexity and connectivity of the aquatic ecosystem to terrestrial and aquatic animal health. These foundational experiences set the stage for her doctoral research, where she investigated the pathogenic mechanisms of hypervirulent Aeromonas hydrophila (vAh) in channel catfish. Her dissertation provided critical insights into the role of these virulence factors and how ecological adaptation drives the expression of specific genes linked to pathogenicity.

Her current research lies at the dynamic intersection of environmental microbiology, aquatic ecology, and bacterial pathogenesis, where she employs a blend of modern molecular biology techniques—such as PCR, transcriptomics, and homologous recombination—alongside proteomics and standard laboratory analyses to investigate the fundamental “How?” and “Why?” of bacterial pathogenesis. Specifically, she is interested in exploring the direct and indirect relationships between bacteria, their adaptive responses to changing environments, and their subsequent ability to cause disease.

Research Interests

Dr. Barger’s research interests span multiple disciplines at the intersection of microbiology, ecology, and aquaculture health. Her primary interests include:

• Bacterial Pathogenesis & Environmental Adaptation: Investigating how environmental factors drive the evolution of virulence in aquatic pathogens.
• Host-Pathogen Interactions: Studying the molecular mechanisms of infection and immune responses in aquaculture species.  Applying transcriptomics, proteomics, and real-time imaging to track pathogen behavior and disease progression.
• Microbial Ecology & Aquatic Health: Exploring how microbial communities influence ecosystem health and the emergence of opportunistic pathogens.

Beyond infectious diseases, Dr. Barger is eager to engage in interdisciplinary collaborations that integrate aquatic ecology, environmental microbiology, and molecular biology to address broader ecological and health challenges. She is particularly interested in using aquatic environments as indicators of ecosystem health, investigating ectosymbiotic relationships between bacteria and ground-dwelling insect larvae as potential sources for natural product discovery, and studying how introduced pathogens like A. hydrophila adapt to utilize native hosts as maintenance reservoirs.

Her long-term vision is to enhance the sustainability of aquaculture industries by advancing the understanding of pathogen dynamics and developing more effective strategies for disease prevention and control. Additionally, she aims to shift the study of emerging pathogens by integrating life history theory into research methodologies, providing a more comprehensive framework for understanding and managing pathogen evolution and virulence.