(571d) Molecular Dynamics Simulations of Hydrophobins Near Gas/Water and Oil/Water Interfaces

Hydrophobins are a class of proteins produced by filamentous fungi in soil. Preliminary experiments suggest that these proteins can encapsulate oil in cylindrical ‘blobs’, or gases in cylindrical bubbles, which implies a striking surface activity. These properties, as well as the abundance and ease of biosynthetic manufacture of hydrophobins, suggest that they could be used as ‘natural’ oil spill dispersants. Here we report molecular dynamics (MD) simulations and potential of mean force (PMF) calculations for a class I hydrophobin, EAS, near gas/water and oil/water interfaces.  Interfacial properties such as free energies, density profiles radius of gyration and secondary structure of the hydrophobins were probed in our simulations using both all-atom and coarse-grained models. The EAS molecules prefer to remain at the interfaces, with the adsorption behavior being strong and irreversible. Significant changes in the radius of gyration and secondary structure of the hydrophobins were observed upon binding to the gas/water and oil/water interfaces. These interfacial properties are relevant for the possible use of hydrophobins as ‘natural’ oil dispersants.