Soft, crystalline, expandable, self-healing porous materials are desirable in numerous applications, including selective separation, gas storage, and sensors. Hyper expandable soft crystalline materials have been synthesized by integrating macromolecular ferritin complexes with polyelectrolytes (Nature <b>557</b>, 86–91, 2018). The protein complexes keep the hydrogel connectivity while maintaining a crystalline structure. The interaction of polymers with the chemically rich protein surfaces determines the capability to engineer new materials. Hence, it is crucial to elucidate the interactions between the different protein surface functional groups (e.g., charged, polar, and hydrophobic) with varying types of charged polymer groups. We use molecular simulations to investigate the interaction of ferritin with uncharged, opposite-charged, and like-charged polymer groups. Ferritin is a 24-meric, quasi-spherical protein cage that exhibits positive and negative polarity surface regions. We observe that the ferritin cage adsorbs positively and negatively charged polyelectrolyte groups due to the surface heterogeneity. We discuss the role of the inner protein residues and the effective protein dielectric constant in the polyelectrolyte adsorption on the protein surface. We foresee our findings to be relevant for designing materials mechanoresponsive to external fields.

Elucidating protein-polymer interfaces in flexible protein lattices

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.