Richard Haburcak
Xu Laboratory
Department of Chemistry
Brandeis University
Ligand-Receptor Binding Modulates Supramolecular Assemblies of Small Peptides
Poster Abstract
Proteins and small molecules exhibit dynamic and intricate binding behavior in biological and biomedical domains. However, while enzymatic transformations that modulate the binding of proteins are common, it is rare for small molecules. We explore how a ligand-receptor binding interaction between Vancomycin and D-Ala-D-Ala modulates the morphology of supramolecular assemblies formed by enzyme-instructed self-assembly (EISA) of small peptides. Without the binding interaction, a precursor molecule is enzymatically dephosphorylated (to give a hydrogelator) and further assembles into long nanofibers; binding interactions cause the formation of precipitates containing short nanofibers. Additionally, by itself, the hydrogelator assembles into nanosheets or nanofibers that do not bind Vancomycin. Addition of a surfactant breaks up the assemblies and restores binding. Further, an excess amount of Vancomycin can disrupt the assembled hydrogelator. The presence of Vancomycin hence biases the assembly pathway, demonstrating how binding modulates self-assembly kinetics. As the first example of such a phenomenon for small molecules, we provide a solution to evaluate the interaction between aggregates and target molecules, and insight into emergent behavior of supramolecular systems.
Personal Statement
Undergraduate research has been a huge part of my college experience. Working in the lab before my freshman year, I found not only a place where I was comfortable but also a place where my opinions were respected and I was challenged. Summer research is an important aspect of the undergraduate experience, as the semesters present endless classes, reading, and assignments that leave hardly any time, at least in my case, for research during the school year. However, research has always been a time to get away from assignments and focus on questions that may have an impact beyond a grade.
Participating in research has not only allowed me to expand my knowledge and work with leaders in the field but to gain personal relationships with other professors at the university. In addition, participating in research has allowed me to work on projects that later went on to be published, including a paper on which I was the first author. This unique experience as a Bauer Research Fellow has pushed me to grow both academically, as many topics covered in courses held potential to be useful in future research. Personally, I have sought out opportunities to teach and mentor other undergraduates. Overall, my undergraduate career would be incredibly different without research, and much less fulfilling.