New Peptidic Foldamer Structures

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

The Macromolecular, Supramolecular and Nanochemistry Program of the Chemistry Division supports the research of Professor Samuel Gellman, who is a faculty member in the Department of Chemistry at the University of Wisconsin - Madison. Gellman's group develops new types of protein-like molecules, based on biologically-inspired designs. Biological systems contain sequence-specific oligomers and polymers that fold to particular shapes. Gellman's laboratory creates unnatural oligomers, or "foldamers", that also adopt discrete shapes. This research employs beta- and gamma-amino acids as alternative building blocks to the natural alpha-amino acids. The protein folding process arranges key subunits into the precise three-dimensional arrays that are necessary for binding to other molecules and catalyzing chemical reactions. A central aim of the Gellman group's research is to develop synthetic foldamers that display protein-like binding and/or catalytic properties. These materials ultimately might surpass proteins in terms of specific functions. This basic research may lead to new types of drug molecules or new types of nanoscale manufacturing capabilities. Conducting this research provides outstanding interdisciplinary training to undergraduates and graduate students. The study of foldamers is an area of chemistry research that offers opportunities for invention in terms of basic research and practical development. This research focuses on cutting-edge challenges in terms of molecular design. One aim is to link understanding of small-molecule conformational propensities to the higher-order structure preferences that emerge in oligomers built from the smaller molecules. In particular, The Gellman group creates secondary structures containing beta- and/or gamma-amino acid residues that form new helical secondary structures with large internal cavities, a feature not found among protein secondary structures. A second aim is to leverage previously acquired knowledge of beta-peptide and alpha/beta-peptide folding behavior to arrange pairs of reactive groups in ways that catalyze synthetically useful reactions. A third aim focuses on quantitative assessment of structure-stability relationships for foldamer helices, information that has been largely unavailable to date. The research group seeks to understand how changes in subunit structure affects the stability of foldamer secondary structures. Progress toward each of these goals may improve understanding of relationships between molecular structure and function.