Date of Award


Document Type

Open Access Dissertation


Public Health

First Advisor

Alan Decho


Marine bacteria often exist in biofilms as communities attached to surfaces, like plastic. Growing concerns exist regarding marine plastics acting as potential vectors of pathogenic Vibrio, especially in a changing climate. It has been generalized that Vibrio vulnificus and Vibrio parahaemolyticus often attach to plastic surfaces. Different strains of these Vibrios exist having different growth and biofilm forming properties. This work evaluated how temperature and strain variability affect V. parahaemolyticus and V. vulnificus biofilm formation and characteristics on glass (GL), low-density polyethylene (LDPE), polypropylene (PP), and polystyrene (PS). This work also evaluated how human body related factors like temperature, pH, nutrient availability, and media composition such as Human Plasma-Like Media (HPLM), Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF) affect in vitro biofilm dispersal processes by human isolated V. parahaemolyticus and V. vulnificus, especially from microplastics. Taken together, these studies suggest that different strains of V. parahaemolyticus and V. vulnificus can rapidly form biofilms with high cell densities and rapidly disperse from different plastic types in vitro. However, these biofilm processes are highly variable and are species-, strain-specific, and dependent on plastic type, especially under different temperatures, pH, nutrients, and fluid compositions. These studies also suggest that different species of Vibrio can rapidly respond to different environmental conditions, especially those related to human digestion.


© 2023, Ryan Eric Leighton

Available for download on Saturday, August 31, 2024