Digging into antibiotic resistance

Claire Brown ’22 discovered her love of research in high school, when she worked as a summer intern in a biochemical engineering lab at Iowa State University. So when she came to Providence from her hometown of Waukee, IA, she pursued her passion right away.

“I started working in Professor Belenky's lab during the second semester of my first year on campus,” she says. “I’ve always been interested in microbiology, and his research involved antibiotic resistance, another topic I’m really interested in, so it felt like a great fit.”

Peter Belenky, PhD, an assistant professor of molecular microbiology and immunology, studies how microbes respond to external stresses like antimicrobial agents and, in turn, how that affects the gut microbiome. One of his doctoral students, Jenna Wurster PhD’21, took Brown under her wing to teach her laboratory and computational skills. Earlier this year, when Wurster needed to expand on her dissertation research, “Claire jumped at the opportunity to spearhead this follow-up question,” she says.

“I really missed being in the lab,“ says Brown, who had been in Iowa during the pandemic. She applied for an Undergraduate Teaching and Research Award (UTRA) so she could return to campus, help Wurster, and begin her senior thesis. The award offers students the necessary financial support to work full time in a faculty member’s lab. “I thought it would be the perfect way to spend my summer,” Brown says.

Wurster’s dissertation research examines how high blood sugar affects the gut microbiome’s response to antibiotics and opportunistic pathogens. With the PhD candidate’s guidance, Brown collected gut samples from “diabetic-like” mice as well as healthy mice. “Claire subsequently singlehandedly extracted nucleic acids from the samples, performed 16S rRNA sequencing [to identify and classify the microbes], and analyzed said data,” Wurster says. 

The pair found that the combination of diabetes and antibiotics made mice more susceptible to Salmonella infection and modified their microbiomes, Brown says. “[Claire] did a tremendous job, and she and Jenna are currently working on resubmitting a manuscript and describing this work,” Belenky adds. 

For her own thesis, Brown wants to see how a diet that’s high in fat and sugar, as opposed to a high-fiber one, combined with antibiotic treatment early in life affects future weight gain. Though the research is still in the early stages, she says, “it’s seeming like the high-fat/high-sugar diets are definitely making an impact.” She adds, “Working in the Belenky lab has definitely reinforced in me the importance of eating healthy and using antibiotics sparingly.”

Brown also took on what she calls a “side quest”: isolating bacteria that were contaminating slides in the lab and running DNA sequences to figure out what they were. “It ended up being Klebsiella oxcytoca, which was unsurprising—Klebsiella are an opportunistic pathogen, and the mice in our facilities have a tendency to be colonized by it,” Brown says.  

Overall, Belenky says, Brown had “a wonderfully productive summer and [she was] a real help to the lab.”

Brown still hasn’t set her sights on a particular career path, “but I know I want more research in my future,” she says. “I've been thinking this since before coming to college, and all of my work with Professor Belenky’s lab has just solidified it.”