Efficient detergent removal using a polydivinylbenzene adsorbent in membrane protein solubilization

Membrane proteins (MPs) are essential for various cellular functions and therefore critical targets for the drug industry. However structural and functional studies of MPs are challenging due to the difficulty and cost of solubilization and purification. Effective solubilization typically requires the incorporation of MPs into detergent micelles. Despite that this is a common practice, it has the potential to destabilize MPs. Alternatively, detergent-free systems have emerged, and reconstitution of MPs in Amphipol (APol) is one of the common methods. Polystyrene beads are generally used for this purpose. We investigated and evaluated the effectiveness of polydivinylbenzene Purolite™ PuroSorb™ PAD600 beads for detergent removal in membrane protein solubilization. To accomplish this, the membrane protein FtsH, solubilized in either DDM or LMNG, was exchanged with varying concentrations of APol, and detergents were removed by Purolite™ PuroSorb™ PAD600 beads. The results demonstrate that Purolite™ PuroSorb™ PAD600 beads are effective for detergent removal when the mass ratio of the Membrane Protein:Amphipol (MP:APol) is increased up to 1:10. The usage of Purolite™ PuroSorb™ PAD600 beads supports biochemical applications for membrane protein isolation and purification studies.