Katherine Davis had just started setting up her chemistry lab at Emory College of Arts Sciences in early 2020 when the looming pandemic forced campus to shut down.
But even done remotely, the assistant chemistry professor’s work — developing and applying techniques to view the reactions from enzymes that use metals (known as metalloenzymes) to help sustain human life — has not escaped notice.
The Arnold and Mabel Beckman Foundation named Davis as one of 11 elite recipients of its Young Investigator Award this summer, just as her lab began the hands-on work exploring light-based methods to trigger and study metalloenzymes’ reactions that have the potential for energy, environmental and medical uses.
The $600,000 award will allow her to continue research that combines X-ray crystallography to create a 3-D picture of all atoms in a metalloenzyme with a type of X-ray spectroscopy to probe the metal.
In this way, Davis creates augmented “movies” that simultaneously capture dynamic behavior of the overall structure and changes to bound metal(s) as enzymes react.
“We know that the structure and metal changes have to work together, but we don’t know a lot about how those dynamics enable metalloenzyme reactivity,” Davis says of the study at the intersection of biology, chemistry and physics.
“It is tricky to get all the different components of the experiment functioning in unison,” she adds. “That challenge is what’s interesting.”
Chemistry is Davis’ adopted field. Her undergraduate degree from the University of Louisville in her home state of Kentucky is in physics, while biophysics was the focus of her doctoral work at Purdue University.
Her first formal work with structural methods was as a Beckman Postdoctoral Fellow in the chemistry department at Princeton University.
“Kate was trained as a physicist and has background in chemistry, but she is always willing to hear her students’ perspectives and learn,” says Kirklin McWhorter, a graduate research assistant in the lab. “It’s a relatively new area of study, so that collaboration makes the research more fun.”
Not only is the approach to studying how enzymes work new, so is much of the experimental setup. That includes a micro-spectrophotometer that McWhorter designed during lockdown.
He’s now building the device, which will allow researchers to measure the way in which the crystallized proteins absorb visible light, a characteristic influenced by the behavior of bound metals.
That makes it useful on projects such as the one McWhorter helped undergraduate researcher Cindy Amaya Lopez through this summer.
Amaya Lopez, a senior chemistry major, completed a project modifying the surface of a protein in ways that promote interactions between molecules, ultimately allowing it to be crystallized and analyzed by X-ray diffraction.
The lab prepped the crystals in liquid nitrogen and sent them to the Argonne National Lab, where they were hit with high-powered X-rays.
The lab’s attempts to determine the structure are ongoing, and the results would be significant given that the Davis team and collaborators at Princeton believe the enzyme could be a future antimicrobial drug target.
Amaya Lopez, who had no previous research experience, credits Davis and her graduate mentors for not only getting her ready to tackle the work but also making her feel part of the team.
“There is pressure being a Hispanic woman and first-generation student in the sciences, but Dr. Davis made a point when I first interviewed to say she’s here to guide and mentor,” Amaya Lopez says. “Her lab has helped me get over that pressure and touch so many different areas of science. She’s humble and says it’s no big deal, but it is. It really is.”
Davis deflects praise, crediting her lab’s five undergraduates and six graduate students on their commitment to collaborating with and learning from each another.
She has similar kudos for students’ commitment to interdisciplinary discovery. The undergraduates in her graduate-level physical biochemistry course last year, which she is again teaching this fall, kept up because of their willingness to tackle new concepts.
That’s why, although she initially shrugs off the prestige of the Young Investigator honor, she admits the four-year award will be significant for her bench work slowed by the pandemic.
“I have been super impressed with the undergraduates who readily take on this research,” Davis says. “With the award, we can now plan for experiments that could take years, knowing the project is supported.”