Dr Robert Best from the National Institutes of Health in the USA will present the Department of Chemistry seminar with a talk entitled, "Investigating the properties of unfolded and intrinsically disordered proteins via experiment and molecular simulation".

Disordered or unfolded proteins are challenging to study by any experimental method due to the diverse ensemble of structures populated — yet their importance in biology is increasingly recognized. The difficulty in experimental interpretation has led to differing conclusions being reached by different experimental methods. This is illustrated by a recent discrepancy between the results of small-angle X-ray scattering  and single-molecule FRET experiments regarding the effect of chemical denaturants on unfolded proteins, and which has been termed one of the key issues in protein folding remaining to be resolved. In a close collaboration with three experimental groups, we have used single molecule FRET, small angle X-ray scattering, 2-focus fluorescence correlation spectroscopy, dynamic light scattering and molecular simulation to investigate this phenomenon. Molecular simulation plays a key role in justifying some of the assumptions made in interpreting experiment, resolving the controversy, and suggesting improved ways for interpreting the experiments.

Dr Robert Best is a graduate from the Department of Chemistry at UCT.