The Future of My Research

PgfS is a novel GT-A type glycosyltransferase (GT) found in the Pgf pathway. GTs are specialized proteins that play a role in both bacteria and animals by transferring a sugar molecule into various different lipid carriers or proteins. This pathway has been associated with the glycosylation of surface proteins critical to the adhesion of S. mutans to collagen. By playing a role in the glycosylation of surface proteins, such as Cnm and Cbm, PgfS contributes to the overall virulence of certain serotypes of S. mutans in human dental caries, resulting in their ability to migrate into the endocardium and cause infective endocarditis. This ability is unique and can be deadly if left untreated. While current predictive models suggest that PgfS exists as a tetramer complex, little research has been done to understand the role oligomerization plays in the function of PgfS.  Furthermore, it is unknown whether PgfS functions only as a result of oligomerization or if the monomers can glycosylate independently of each other. Thus, this project aims to elucidate the importance of oligomerization in PgfS glycosylation. This will be achieved through the isolation of PgfS monomers through a point mutation that disrupts oligomerization. Oligomerization is the process by which protein subunits come together to form larger complexes. Once isolated, the monomers will be analyzed through an in-vitro glycosylation assay to determine whether glycosylation occurs in lipidic carriers while PgfS is unable to oligomerize. Currently, it is predicted that PgfS must oligomerize to properly function due to similar GT-A proteins utilizing a mechanism viable only through oligomerization. The results of this study will ultimately contribute to a greater understanding of PgfS and related GT-As in terms of glycosylation, thereby helping to establish a potential novel target for future drug development. 

Initially, this topic was a part of a much larger study spearheaded by my graduate student in understanding the role of this GT protein and other homologous proteins. However, rather unexpectedly, a collaboration between a lab at Princeton and Oxford uploaded a pre-print paper on a very similar topic. Whenever a pre-print is released, there is little to no reason to continue working on your specific research question if it is answered by them already. Thus, this very project was planned to be abandoned. However, this gave gave me an opportunity.

Since the pre-print made by the collaboration only looked at the wild-type protein, or simply the protein found naturally in organisms, a study based on a mutant protein could still be a viable study to conduct. Given this, my graduate student encouraged me to continue working on the same protein and work independently on it since it was the perfect scope for someone new to research. The hope will be to look at other proteins similar to PgfS and determine the importance of the complexes made by the subunits.

This misfortune taught me a valuable lesson: research is never rigid. Unexpected things happen all the time with both data collection and other research projects. Because of this, it's important to always stay flexible and ready to change direction whenever there is a need to do so. Since it was my first time experiencing such a thing, having mentors by my side allowed me to navigate this bump. Had it not been for my graduate student's ingenuity, I would've just decided to abandon the project and scrap all the data I had gather up until that point.