Meet Gabriella Rizzo

Program
Genetics, Cellular and Molecular Biology, PhD

Degree you currently have
B.S. in Microbiology from UMass Amherst

Hometown
Nutley, NJ

Why did you select your program?
I first joined the Weber Lab through Nebraska’s Bioenergy Systems Summer Research Program in 2023. I was immediately fascinated by the questions the lab was asking: Can microorganisms essentially “eat” rocks? How do they transform minerals or contribute to the formation of new ones? How can a community of six microorganisms cooperate so closely that they thrive together in an environment where they might not survive alone? And what can these interactions teach us about the possibility of life on planets such as Mars?

Just as importantly, I felt that I had found my home at Nebraska. From the moment I arrived, continuing my research here felt less like a question and more like the natural next step.

What has been your best experience as a graduate student at Nebraska?
One of my best experiences has been sharing science with communities across Nebraska. I have participated in Dinosaurs & Disasters, an annual hands-on science event at Morrill Hall, and connected with high schools to develop an “Astrobiology in High School” guide. Because Nebraska does not currently have a formal astrobiology pathway, I want students to know that careers exploring life beyond Earth are still within their reach.

I have also loved becoming part of the broader Nebraska community—from joining campus affinity groups such as Pride Affinity, to exploring local businesses and communities across the state. Having lived in the Northeast my entire life, I have been especially touched by the hospitality and sense of connection I have found in the Midwest.

Who have been some of your strongest mentors or role models here?
I have been fortunate to learn from many exceptional faculty members in the School of Biological Sciences, including Dr. Wayne Riekhof, Dr. Ken Nickerson, Dr. Sherilyn Fritz, Dr. Etsuko Moriyama, and Dr. Heriberto Cerutti. There are truly too many to name.

Above all, my advisor, Dr. Karrie Weber, has been one of my strongest mentors. I admire not only the scientific careers and research accomplishments of these faculty members, but also the genuine care, enthusiasm, and commitment they bring to their students, the department, and their fields. They have shown me that being an excellent scientist and being a compassionate mentor are not separate goals.

Do you have research and/or creative activity experience?
Yes! My research centers on microorganisms that survive in extreme environments and what they can teach us about microbial life both on Earth and beyond it.

At Nebraska, I use a naturally derived microbial enrichment culture to investigate what microbial interactions and mineral transformations may look like below Earth’s surface. My work brings together microbiology, geology, and chemistry to examine how microorganisms share resources, use hydrogen for energy, interact with rocks and minerals, and influence their surrounding environment. Understanding these fundamental subsurface processes also helps us identify chemical signs of life that could inform future searches for life on Mars and other worlds.

I have also studied heat-loving microorganisms from deep-sea hydrothermal vents, helped identify a new methane-producing species, and investigated salt-loving microbes that could support manufacturing in space. Most recently, at the Marine Biological Laboratory, I isolated a heat-loving bacterium from a commercial dishwasher and studied its ability to form resilient biofilms on silicone and stainless steel.

Although these projects span environments from Nebraska’s subsurface to the deep ocean and outer space, they are connected by one question: How does microbial life adapt, cooperate, and persist under extreme conditions?

What are your plans once you have earned the degree?
After earning my Ph.D., I hope to pursue a career in NASA astrobiology and contribute to missions exploring potentially habitable environments and searching for life beyond Earth—from Mars to ocean worlds such as Europa and Enceladus.

As a microbiologist, I want to bring a stronger biological perspective to the earliest stages of mission planning. Determining whether an environment could support life requires more than identifying water or promising chemistry; we must also understand how microorganisms obtain energy, adapt to extreme conditions, and leave behind detectable evidence of their activity. Those biological questions should help guide which instruments we send, how sensitive they must be, and how we interpret the data they return.

Ultimately, I hope to bridge the gap between what is biologically possible and what is technologically feasible, helping future missions ask better questions—and giving us the best possible chance of recognizing life if we find it.