Steven Romberger, Ph.D.

Edward J. Smerek Chair in Mathematics, the Sciences, and Technology; Director of the Office of Scholarly Endeavors; Associate Professor of Chemistry; Coordinator of Biochemistry Major

Contact

Education

Ph.D. Biochemistry, Microbiology, and Molecular Biology, Pennsylvania State University, 2011
B.S. Biochemistry, Susquehanna University, 2005

Until it happened, I never imagined myself as a college professor. While finishing up my Ph.D., I took a position as an adjunct professor – at the time, I saw my time in academia as a temporary thing until I found the right position in industry. That adjunct position evolved into a visiting professor at a neighboring university and before I realized it, I was doing most of the things that a more traditional professor was doing. That led me to do a job search and that was when I found this eclectic, interdisciplinary college called Hiram.

Steven Romberger is an Associate Professor of Chemistry and Coordinator of the Biochemistry major. He currently teaches courses in biochemistry and analytical chemistry but has previously taught in the first-year program. His research focuses on studying the biochemistry of photosynthesis in unusual organisms. Of particular interest are the poorly understood heliobacteria. He maintains an active research group with several undergraduate collaborators. When not in the laboratory, he can likely be found with his wife Stacy throwing ball for their cattle dogs Lily and Argos and, on occasion, has been spotted hiking the trails near their home in Hiram.

ADDITIONAL RESPONSIBILITIES

Mentoring my research students
Advisor of the Chemistry Club (Request More Information)
Director of the Office of Scholarly Endeavors
Coordinator for Hiram’s Choose Ohio First program
Sugar Day Coordinator (Learn More About Sugar Day)

Steven P. Romberger and John H. Golbeck (2012), “The FX iron-sulfur cluster serves as the terminal bound electron acceptor in heliobacterial reaction centers.” Photosynthesis Research, 111(3), 285 – 290.
Josephine Sarrou, Zahid Khan, John Cowgill, Su Lin, Daniel Brune, Steven P. Romberger, John H. Golbeck and Kevin E. Redding (2012), “Purification of the photosynthetic reaction center from Heliobacterium modesticaldum.” Photosynthesis Research,111(3), 291 – 302.
Yusuke Tsukatani, Steven P. Romberger, John H. Golbeck and Donald A. Bryant (2012), “Isolation and characterization of a homodimeric type-I reaction center complex from Candidatus Chloracidobacterium thermophilum, an aerobic chlorophototroph.” Journal of Biological Chemistry, 287(8), 5720-5732.
Amaya M. Garcia Costas, Yusuke Tsukatani, Steven P. Romberger, Gert T. Oostergetel, Egbert J.Boekema, John H. Golbeck, Donald A. Bryant (2011), “Ultrastructural analysis and identification of envelope proteins of “Candidatus Chloracidobacterium thermophilum” chlorosomes.” Journal of Bacteriology, 193, 6701-6711.
Steven P. Romberger, Christian Castro, Yili Sun and John H. Golbeck (2010), “Identification and characterization of PshBII, a second FA/FB – containing polypeptide in the photosynthetic reaction center of Heliobacterium modesticaldum.” Photosynthesis Research, 104, 293 – 304.

Basic Biochemistry
Intermediate Biochemistry
Quantitative Analysis
Senior Seminar
Research Techniques in Biochemistry
Various Special Topics Courses

Favorite Course TO TEACH

“This is actually something of a trick question since I don’t have one particular favorite course. Instead, I have a few favorite topics or ideas that show up in different courses. For instance, much of my scientific background is in protein structure and function and these are two topics that we spend significant time on in Basic Biochemistry, but we also do a semester-long, student-designed enzymology research project in Intermediate Biochemistry, so those two sections are really fun sections to teach. Quantitative Analysis completely changed the way I thought about chemistry as a student, so helping my own students through that process while teaching that same course is really satisfying.”

Research

Lab Research Summary

Photosynthesis is often taught as the conversion of water and carbon dioxide into glucose and oxygen using the energy of captured light. While this is not an incorrect statement, it paints a rather incomplete picture. One might say it is 2/8 of the picture, as there are 8 distinct taxa of photosynthetic organisms and only 2 do photosynthesis in this manner: plants and cyanobacteria (formerly called blue-green algae). To be fair, those are the two that are most important from a human perspective because they are the only two who can convert water into oxygen. Of the six taxa remaining, only three convert carbon dioxide into other compounds and they are never as complex as the 6-carbon compound glucose; they will synthesis much simpler, 3-carbon compounds such as pyruvate. By subtraction then, there are three taxa of photosynthetic organisms left and all we really know about their photosynthetic reactions are something plus light presumably yields something else.

My research group predominantly works with one of those three taxa, a group of anaerobic bacteria called the heliobacteria, and we are trying to determine the something and something else. Our recent results suggest that the heliobacteria are photosynthetically very different and are the only known phototrophs to function in a light-limited manner. Unlike other organisms, where it is the later chemical or biological reactions that limit the rate of photosynthesis, it is the initial photochemical reaction, which turns light into chemical energy, that limits photosynthesis in the heliobacteria.

Check out this poster for a recent summary of our findings.

Figure 1. Diagram showing the relationship between the eight distinct taxa of phototrophs and their balanced equation of photosynthesis. Each taxon is colored to match the most common colors of the organisms in that group. You’ll notice that photosynthesis actually covers the entire visible spectrum and that a few of the names are something of misnomers (for instance, the green-sulfur bacteria have members species that brown)

In a broader context, while the Romberger research group is focused on the biochemistry of photosynthesis, we have a diversity of scientific interests. From a more fundamental perspective, we aim to better understand the structure-function relationships of proteins and how those relationships impact the biology of the parent organism. While we emphasize enzymology and advanced spectroscopic techniques, such as whole-cell spectroscopy, we use a variety of methods to investigate photosynthesis, such as bioinformatics, protein structure homology modeling, and classic microbiology. Because of the intimate connection between photosynthesis, solar energy, and sustainability, we often have projects related to green chemistry, especially those that bridge the gap between analytical chemistry and biochemistry. Finally, because of my own interests in pedagogy and the scientific community’s recognition of the reproducibility crisis, our laboratory regularly hosts course-based and independent research projects that reevaluate previous discoveries using more modern techniques. In this way, our lab contributes to the preservation and reproducibility of scientific knowledge. Check out the posters below to see some of the work recently presented by students in the Romberger group

Student Research Poster Presentations

“I have a pretty active research group, typically with 6 – 12 students at any one time, all working on different projects. Thus, making sure they each get the one-on-one mentoring to be successful with their projects, as well as the behind-the-scenes management of those projects and my laboratory space (i.e. ordering supplies, maintaining equipment, etc.) is a big responsibility.”