The Physics department colloquia are usually on Friday afternoons at 3:30 pm in Lapham Hall Room 160. Coffee and cookies are served at 3:15 pm in the same room. Anyone is welcome.

Untangling Conformational Heterogeneity in Allosteric Enzymes
Dr. Nozomi Ando, Assistant Professor of Chemistry, Princeton University

Biology uses protein allostery at key junctions in metabolic pathways. In this talk, I will discuss the use of small-angle X-ray scattering (SAXS) to examine complex allosteric enzymes that exist as conformational mixtures in solution. Examples of such enzymes include ribonucleotide reductase (RNR), an enzyme required by all organisms to produce DNA, and phenylalanine hydroxylase (PheH), an enzyme that plays a critical role in cognitive health. Using a combination of crystallography and SAXS, I will discuss how allosteric regulation of these enzymes entails dramatic conformational changes. I will also present the first demonstration of evolving factor analysis (EFA), a powerful variant of singular value decomposition, to data obtained by chromatography-coupled SAXS.