The enzyme phenylalanine hydroxylase (PAH) is a highly dynamic, allosterically regulated tetramer, and its dysfunction is the root cause of the metabolic disorder phenylketonuria (PKU). Understanding how PAH switches between states – and the role of ligand binding and disease-associated mutations in the transition – requires a powerful, integrated biophysical approach.

In this on-demand webinar, Kushol shows how a suite of five solution-based techniques (mass photometry, AUC, SEC-MALS, SEC-SAXS, and time-resolved SAXS) were used to define a two-state quaternary landscape for PAH and identify the structural transitions that drive enzyme activation. These insights are further strengthened by newly determined cryo-EM structures that capture critical regulatory domain movements and reveal the atomic-level mechanisms of allosteric switching.

Together, these approaches represent a modern, multimodal framework for dissecting the behavior of complex, heterogeneous enzymes – deepening our understanding of PAH regulation and PKU-associated dysfunction.

You also find out about Refeyn’s innovation MyMassMP, a mass photometer designed for rapid sample checks prior to cryo-EM, native MS, SPR, and BLI.