Giant "Breathing" Proteinosomes with Jellyfish-like Property.

The design and construction of "breathing" self-assemblies has been a rather popular topic due to their potential in materials science and nanotechnology. Inspired by the "breathing" behavior of natural jellyfish, herein, we presented the construction of a giant "breathing" proteinosome through an interfacial self-assembly of proteins and surfactants at the oil/water interface of emulsions: The proteinosome displays "breathing" behavior and can swell and shrink for multiple cycles by protein folding and unfolding through the alternate addition and removal of denaturant; more importantly, when green fluorescent proteins were selected as alternative protein building blocks, the fluorescence of proteinosome can be reversibly switched on/off just like the behavior of jellyfish. Moreover, accompanied by reversible swelling and shrinking and on/off fluorescence, the expanded and shrunk membrane pore can be tuned for distinguishing quantum dots of different sizes. The folding-responsive breathing behavior of intelligent proteinosomes provides a platform for functional biomaterials.