Ranaspumin-2 (Rsn-2) is a surfactant protein that has been identified as an important component in the foam nests of the tungara frog. It is not immediately obvious structurally, as in the case of other surfactant proteins such as the hydrophobins, how or why Rsn-2 is so surface active. Previous work has suggested that Rsn-2 undergoes an 'un-hinging’ mechanism at the interface, whereby the hydrophobic core of the protein is exposed to the interface whilst keeping its overall secondary structure motifs. In this work we study the interfacial activity of both wild type Rsn-2 and several mutants using both experiment and molecular dynamics simulations. We find the interfacial adsorption of Rsn-2 is described by a 2-step process and identify a mechanism by which the protein undergoes this unusual 'clam shell-like’ structural transition.
This is a weekly series of informal talks given primarily by members of the soft condensed matter and statistical mechanics groups, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..