Persistence in the Lab Pays Off for Chemistry Senior

For Martha Spletzer, chemistry is all about the reaction.

"Chemistry is amazing because it will tell you how tiny, tiny things are moving to give larger results," said Spletzer, who is a senior on the biochemistry track. "They'll tell you how bonds are forming and breaking and why they're forming and breaking."

A member of the Guo Group run by Yisong (Alex) Guo, associate professor of chemistry, Spletzer studies an enzyme, known as TqaL, which contains iron ions. Since enzymes are organic molecules, they typically do not contain ions from the heavy metal groups, making this type of enzyme unusual.

The Guo Group hopes to use this enzyme to target specific proteins and promote healthy cell functions. To learn how the enzyme can be used, first the team needs to understand how the enzyme and its functional groups react.

Spletzer's role is to investigate the intermediate phases of reactions that form when the enzyme is exposed to a substrate. She uses spectroscopy to learn the different configurations of the enzyme and to determine which configuration is most effective. She further utilizes bioinformatics to discover new enzymes that exhibit a similar enzymatic behavior as that of TqaL in the genomic data.

An enzymatic reaction occurs in a step-wise fashion, where different molecules are formed then consumed as the final molecule or compound is created. These intermediate species are important to fine tuning catalysis and the reaction's final product.

"It was interesting seeing what kinds of intermediate species can form during a mechanism," Spletzer said. "Because you're working with an iron atom within an active site, you can have all kinds of different activities and different intermediate species."

Spletzer works closely with Jared Paris, a Ph.D. student in the Guo group. Along with Guo, they are coauthors on an upcoming paper.

"Martha is persistent," Guo said. "Early on when the protein expression was not going very well, she and Jared had tried a lot of different things. But she was still persistent, which I think is a very important aspect of a good scientist."

Paris was happy to see her achievements.

"It has been quite rewarding to mentor Martha over these past few years, particularly with how much she has grown as a scientist," Paris said. "It has been great seeing her gain confidence in designing experiments and interpreting data. She is also an extremely dedicated student and would readily connect what she was learning in the classroom with whatever our latest research obstacle was. She has a bright future ahead of her."

Outside of the lab, Spletzer finds an outlet in creative writing. She was accepted into Carnegie Mellon's Fifth Year Scholar program for the 2023-2024 academic year, where she will conduct a community impact program and take creative writing courses and others outside of her chemistry major.