Bacteria Get Sick, Too, Says Utah State University Undergraduate Researcher

Like other living things, bacteria get sick, too, says Utah State University biochemist Brendon Guinn.

The single-celled organisms are vulnerable to viruses, which depend on bacteria to replicate.

“Viruses can’t reproduce on their own, so they attach to bacterial cells, injecting their DNA into the cells, which often damages or kills the host cell and allows new viruses colonize additional bacterial cells,” says Guinn, an undergraduate researcher in the lab of USU Chemistry and Biochemistry faculty mentor Ryan Jackson.

But bacteria aren’t entirely defenseless, he says.

“Many bacteria develop an immune system, known as CRISPR, to defend themselves against invading viruses called phages,” says Guinn, who was selected as a USU Peak Summer Undergraduate Research Fellow for summer 2024.

Guinn is among about 30 USU scholars who’ll present research posters to state legislators in Salt Lake City on Thursday, Feb. 20, as part of 2025 Undergraduate Research Day on Utah’s Capitol Hill. The annual event, initiated in 2000, brings scholars from Utah State and the University of Utah to the hub of legislative activity to highlight the importance of university research to the welfare of local communities and in preparing Utah scholars to tackle future challenges.

CRISPR, Guinn says, is an acronym for “clustered regularly interspaced short palindromic repeats.” CRISPR systems are simple yet powerful genome editors capable of chopping up the DNA of threatening phages.

“Bacteria are really amazing,” Guinn says. “Humans need entire organs to develop functional immune systems, yet bacteria can do it with several proteins in a single cell.”

Guinn, who was awarded a College of Science Undergraduate Research Minigrant, along with a USU Undergraduate Research and Creative Opportunities (URCO) grant to support his research efforts, studies a lesser-known Type IV CRISPR system studied by the Jackson Lab.

“A lot of people know about CRISPR-Cas9, which has been used in breakthrough treatment of sickle cell anemia,” Guinn says. “We’re just beginning to learn about Type IV systems, including CRISPR-Cas12a2 which, unlike CRISPR-Cas9, completely destroys the DNA in an infected cell.”

A 2019 graduate of Utah’s American Fork High School, Guinn chose Utah State because his mother is a USU alumna and because of the research opportunities.

“I wanted to pursue medical studies or something medically adjacent,” he says. “I sought out Dr. Jackson during my freshman year, as I’d read about his CRISPR research.”

Jackson, USU’s R. Gaurth Hansen Professor, put Guinn to work in his lab, starting with simple tasks.

“At first I volunteered once a week, washing up lab equipment,” Guinn says. “Gradually, I learned more and more about the lab, and learned basic lab techniques and procedures.”

The undergrad biochemistry major spent more and more hours in the lab.

“Dr. Jackson and doctoral student Thom Hallmark began giving me assignments, where I performed procedures over and over until I mastered them,” he says. “With each assignment, they gave me more responsibilities, until I was ready to take on a project of my own.”

Those long hours and late nights, Guinn says, prepared him to apply for the USU funding opportunities that, he hopes, will propel him to graduate studies in biochemistry following graduation this spring.

“The Peak Fellowship, along with the URCO and minigrant, enabled me to focus solely on research this past summer,” he says. “I’d never done such mentally intensive work full-time. It was difficult, but it taught me I could push through challenges.”

Gaining that realization and confidence, he says, is critical for undergraduates.

“Pursuing research is achievable, but you have to decide you really want it and commit to it,” Guinn says. “You have to take the initiative and chase down opportunities with professors. Don’t be afraid to take the first step yourself.”