Mechanism of Coupled Protein Folding and Ligand Binding Through Multiple Pathways

Graduate student Kyle Daniels (Oas lab) has determined a complex protein folding mechanism.

This study which was recently published in The Journal of the American Chemical Society, employed stopped-flow fluorescence data, x-ray crystallography and isothermal titration calorimetry to deduce the equilibrium flux through 18 possible pathways in the coupled folding and pyrophosphate binding reaction of RNase P protein.  The work involved the collaboration of three other groups whose expertise includes Bayesian statistics, protein crystallography and enzymology.  It represents the first application of the concept of flux to determine the mechanism by which an intrinsically disordered protein is induced to fold by the addition of ligand.  As depicted below, which pathways have the greatest flux depends strongly on ligand concentration.