40th Annual Naff Symposium
University of Kentucky
College of Arts & Sciences
Dr. Todd Yeates, Department of Chemistry and Biochemistry at UCLA
Abstract: Nature has evolved myriad sophisticated structures based on the assembly of protein subunits. Many types of natural protein assemblies (such as virus capsids) have been studied extensively, while a number of equally sophisticated natural protein assemblies are only beginning to be appreciated. Among the latter group is a broad class of giant, capsid-like assemblies referred to as bacterial microcompartments. They serve as primitive metabolic organelles in many bacteria by encapsulating sequentially acting enzymes within a selectively permeable protein shell. Our laboratory has elucidated key mechanisms of these protein-based bacterial organelles through structural studies. On the engineering side, sophisticated natural protein assemblies like these have for many years represented an ultimate goal in protein design. By exploiting principles of symmetry that are shared by nearly all natural self-assembling structures, we have developed methods for engineering novel proteins that assemble to form a variety of complex, symmetric architectures. Recent successful designs include hollow protein cages composed of 12 or 24 identical subunits in cubic arrangements. Symmetric materials that extend by growth in two or three dimensions are also possible. Natural and engineered protein assemblies will be discussed, along with their future prospects for synthetic biology and biomedical applications.