Development of a Flow Cytometry Method for the Identification and Enumeration of Enterococcus faecalis

<p>A multi-color flow cytometry method coupled with fluorescent staining was developed to detect and quantify <em>E. faecalis</em> concentrations in coastal waters as an alternative to the traditional membrane filtration method. The developed method was used to characterize <em>E. faecalis </em>during batch growth and yielded consistent results across the various physiological states of the cells. Additionally, the application of propidium iodide (i.e., a viability stain), afforded the method the ability to differentiate between cells with intact and compromised cell membranes, which raises the potential of quantifying cells that are in viable-but-non-culturable (VBNC) state. Initial field test using natural seawater samples spiked with <em>E. faecalis</em>, demonstrated high accuracy (98-120 % recovery rate) and precision (6-10% CV) of the method to detect <em>E. faecalis</em>. The short analysis time (~ 2 hours) and absence of labor-intensive steps (vacuum filtration, agar plating, and a series of confirmatory steps), increase the potential for the method to increase the throughput of routine monitoring of water quality. A shorter response time to potential outbreaks of <em>E. faecalis</em> and the ability to quantify VBNC cells would further reduce risks to public health and safety.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Masters Thesis

Year dc:date.available

2024

Author dc:creator

• Magbitang, Riza

Contributors dc:contributor

• Kristina Mojica
• Alan Shiller
• Stephan Howden

• E. faecalis
• Multi-color Flow Cytometry
• Fluorescently labeled Antibodies
• Analytical Chemistry
• Environmental Monitoring
• Marine Biology
• Water Resource Management

Repository record dc:identifier

https://aquila.usm.edu/masters_theses/1048

OAI identifier oai:identifier

oai:aquila.usm.edu:masters_theses-2141