Tue, Dec. 16, 2014, 3:15pm - 5:30pm
Frick Chemistry Laboratory, Taylor Auditorium
Host: Sal Torquato
3:15 p.m. – Public research seminar, Taylor Auditorium
4:30 p.m. – Research proposal, A81
Design principles for heterogeneous structure synthesis: Lessons from biology
Complex biological structures like the ribosome are often made of many distinct species of macromolecules that are non-covalently bound into a heterogeneous structure. Biological systems assemble such structures through means that are fundamentally different from synthetic approaches; they are able to fix errors, fine tune assemblies and repurpose structures. By unraveling the principles behind these systems, we can not only improve existing synthetic methods of materials science but also discover completely new kinds of materials. However, results from the physical chemistry of systems with only a few distinct species are inadequate to understand the highly heterogeneous systems found in biology.
In this talk, I will first show that even basic questions about the assembly of heterogeneous structures, such as the optimal concentrations of different species in protein complexes or synthetic DNA strand assemblies, can have counter-intuitive answers from the perspective of homogeneous systems. In the second part of the talk, I will discuss a basic assumption in current frameworks for both biological and synthetic molecular self-assembly – namely, that only one structure can be targeted by the static interactions between a set of molecular species. In contrast, I will show, using results from spin glasses, that we can “store’’ and “retrieve’’ multiple desired structures in the static interactions of a highly heterogeneous system. Interference between different stored structures is minimized by a notion of frustration inherent in any 2-dim or 3-dim supramolecular structure.