Date of Graduation

Summer 2021


Master of Science in Biology



Committee Chair

Babur Mirza


Bacterial impairment of water systems is a major issue facing mankind. Bacteria that are introduced into a system have the potential to cause harmful diseases to wildlife and humans. In Greene and Polk counties, many water systems have become bacterially impaired over the years. Despite this, little is known about the contamination of known harmful bacteria in this region. To address this issue, I investigated the presence of known human pathogens across water systems in these two counties, many of which have displayed high levels of E. coli and fecal indicator microorganisms over many years. I used a high-throughput sequencing approach to determine what pathogens were present at these locations. Overall, it was found that pathogens such as Legionella, Shigella/E. coli, and Yersinia were found in high abundance in one site in the Little Sac watershed and one site in the Pearson Creek watershed. Additionally, these pathogens were found to be abundant at Sequiota Park’s spring at different time points across a year. qPCR was also used to determine the presence of four commonly reported cyanotoxin genes: cylindrospermopsin, anatoxin-a, microcystin, and saxitoxin. Cyanotoxins are produced by Cyanobacteria and are known to cause various diseases. Of the four tested, only the anatoxin-a gene was detected. It was found that there was an increase in anatoxin-a containing cyanobacteria at site LS_171. Additionally, this site displayed increased abundance in Planktothrix-related sequences, suggesting that the increase in the anatoxin-a gene could be due to the increase in Planktothrix at this site. Conclusively, utilizing these methods may be able to help prevent diseases outbreaks associated with these pathogens.


bacterial impairment, bacterial pathogens, cyanobacteria, cyanotoxins, anatoxin-a, high-throughput sequencing, qPCR

Subject Categories

Environmental Health and Protection | Environmental Microbiology and Microbial Ecology | Environmental Monitoring | Pathogenic Microbiology


© John C. Kincaid

Open Access