Four senior students in Dr. Maddison Melchionna鈥檚 microbial genetics lab have dived into a project to study what might be hiding in the clear waters of 含羞草研究所鈥檚 iconic Lake Susan.
Hannah Jarboe (Mechanicsville, MD), Tamiya Bruce (Charleston, SC), Jaycee Beckham (Mount Pleasant, SC), and Caleb Potter (Mill Spring, NC) make up the dedicated lab team. Their mission is to isolate bacteria from Lake Susan’s water samples and cultivate them under controlled conditions in the laboratory.

To identify the bacteria, the four students are using Bergey鈥檚 Manual of Systematic Bacteriology, a 1,000+ page 鈥渂ible of microbiology.鈥 This extensive reference provides detailed information about bacterial species, including their swimming capabilities, appearance on Petri dishes, and microscopic characteristics.
So far, the team has isolated several colonies in Petri dishes, and they鈥檝e successfully identified their first specimen.
鈥淚t鈥檚 called Serratia marcescens, and it鈥檚 actually pretty smelly,鈥 Hannah admitted. 鈥淚t smells like dead fish along with being bright red. It looks like lipstick but doesn鈥檛 smell as nice.鈥
鈥淎t first, we were debating on whether or not it was even Serratia marcescens because it was so different from what we’ve seen in the lab,鈥 Jaycee added. 鈥淟ab strains are usually not a very pigmented red. They’re more of a muted red versus what we’ve gotten from Lake Susan is very red.鈥
Serratia bacteria are commonly found in surface waters. According to the National Institutes of Health, although Serratia marcescens is an organism that does not cause primary invasive diseases, it can produce an infection when it gains access to a compromised host.
鈥淭here are opportunistic pathogens that will take advantage if you get water in your system,鈥 Jaycee explained, 鈥渁nd if they can get in your gut, it鈥檚 not pretty.鈥
After identifying the bacteria, the students plan to test for forms of antibiotic resistance, a significant global health concern. Antibiotic resistance occurs when bacteria mutate or change their physiologies in response to antibiotics, so that certain antibiotics can no longer be used to treat bacterial infections.

鈥淩esistance is important because if one of us goes for a swim in the lake and we accidentally ingest some of the bacteria that have developed resistance to certain antibiotics, then treatment of these infections becomes a problem,鈥 said Hannah.
Professor Melchionna, Assistant Professor of Natural Science at 含羞草研究所, expressed pride in the accomplishments of Hannah, Tamiya, Jaycee, and Caleb and the knowledge they鈥檝e acquired along the way.
鈥淚鈥檝e had all of them in different classes, and I鈥檓 really excited they came together serendipitously in this one class,鈥 Dr. Melchionna said. 鈥淭hese students work hard, and they鈥檙e really curious.鈥
Beyond Lake Susan, the class may extend their research to Lake Tomahawk in Black Mountain. However, the four students are already grateful for the valuable lab experience they鈥檝e gained this semester.
鈥淲e are learning techniques that could be super helpful for a lot of us in our future,鈥 said Hannah, who plans to attend graduate school next year. 鈥淕od鈥檚 creation is beautiful, and it鈥檚 always good to see whether it鈥檚 outside or in a lab.鈥
鈥淎s a Christian, we’re called to serve people,鈥 Jaycee added. 鈥淚f what we’re doing in the lab can help us find antibiotic resistance and different bacteria and possibly help other people, then that’s what I want to help do.鈥
