Cell free expression in proteinosomes prepared from native protein-PNIPAAm conjugates

Abstract

Towards the goal of building synthetic cells from the bottom-up, the establishment of micrometer-sized compartments that contain and support cell free transcription and translation that couple cellular structure to function is of critical importance. Proteinosomes, formed from crosslinked cationized protein-polymer conjugates offer a promising solution to membrane-bound compartmentalisation with an open, semi-permeable membrane. Critically, to date, there have been no demonstration of cell free transcription and translation within water-in-water proteinosomes. Herein, we present a novel approach to the fabrication of proteinosomes directly from native protein-polymer (BSA-PNIPAAm) conjugates. We show that these native proteinosomes offer an excellent alternative as artificial cell chassis. Significantly, the native proteinosomes are stable under high salt conditions and can consequently support cell free transcription and translation. The native proteinosomes offer enhanced protein expression compared to proteinosomes prepared from traditional methodologies. Furthermore, we demonstrate the integration of proteinosomes into higher order cellular architectures with membrane free compartments and liposomes. The integration of bioinspired architectural elements with the central dogma is an essential building block for realizing minimal synthetic cells and is key for exploiting artificial cells in real-world applications.