Vibrio cholerae, a natural inhabitant of the marine environment, is capable of evolving from a strictly environmental to a pathogenic lifestyle. Upon this transition, the bacterium may cause the severe diarrheal disease cholera. To cause disease, ingested V. cholerae must survive a number of host defenses. Similarly, within the marine, V. cholerae is subject to various ecological pressures; these pressures may prompt the bacterium to develop adaptations that increase their survival in the environment as well as in response to host defenses. In the marine, V. cholerae can be found in different fractions: in sediment, in association with cyanobacteria, or in water. It is possible that different pressures found in each of these fractions may lead to specific host-associated phenotypes that increase the potential of V. cholerae to emerge as a pathogen. V. cholerae that do evolve into pathogens comprise a phylogenetically confined subset within the species that encode allelic variations of core genes, such as ompU, that confer virulence adaptations. In this study, we examined whether environmental V. cholerae isolated from different marine fractions exhibit distinct host-associated phenotypes and encode virulence associated alleles. We found that V. cholerae we isolated from different marine fractions did not show differences among the host-associated phenotypes tested, nor did fraction appear to select for and enrich a given virulence associated allele. Nevertheless, this study provides insight on the role of environmental conditions on the pathogenic potential of environmental V. cholerae.

Thesis Completion




Thesis Chair/Advisor

Almagro-Moreno, Salvador


Bachelor of Science (B.S.)


College of Medicine


Burnett School of Biomedical Sciences

Degree Program

Biomedical Sciences



Access Status

Campus Access

Length of Campus-only Access

5 years

Release Date