Supramolecular Protein Assembly Retains Its Structural Integrity at Liquid–Liquid Interface

Abstract

Adsorption of globular proteins at liquid–liquid interface results in compromised structures and functionalities to maintain a thermodynamically favorable state. However, the structural behavior of highly symmetrical supramolecular protein assemblies, adsorbed at the liquid–liquid interface, is not well understood. In this study, a model supramolecular protein assembly, E2 protein nanocage, a dodecahedral cage‐structured protein, is studied upon adsorption at the oil–water interface by both theoretical and experimental analyses. Molecular dynamics simulations and force estimation reveal that noncovalent interactions between E2 subunits dominate over the tangential force experienced by E2 at the interface allowing it to retain its structural integrity. Experimental analyses confirm the adsorption of E2 on the liquid–liquid interface with negligible penetration depth. Molecular structural analyses further suggest the structural integrity of the caged structure of E2 at the oil–water interface with minimal change in the tertiary and secondary structures. In conclusion, this study brings new insights into the behavior of highly symmetrical supramolecular protein assemblies at liquid–liquid interface which is important in preserving their functionalities.

Recent Advances on Pickering Emulsions Stabilized by Diverse Edible Particles: Stability Mechanism and Applications

“…Nanocages are similar to spheres so the stability mechanism of nanocages resembles that of spherical particles (22). Sarker et al (54,87) prepared dodecahedral hollow protein nanocages using E2 protein to stabilize pH-responsive Pickering emulsions and proved that the cage-shaped solid particles show assembled structure of approximately 25 nm in diameter with 12 openings of about 5 nm each (Figure 3C).…”