Integration of an Inducer-Producing Metabolic Pathway in an Artificial Cell

Synthetic cell-like system are common architectures employed to study biological processes (enzyme-catalysed reactions, simple metabolic pathways, transcription/translation) and inter-cellular communication (between artificial cells or between artificial and natural cells) or as drug-delivery and gene therapy agents. Conventional artificial cells are based on the self assembly of lipid components (liposomes, water-oil lipid droplets) providing an amphiphilic environment essential for integrating membrane proteins. Alternative synthetic cell-like systems such as polymersomes were developed to offset lipid systems which can be limited by the impermeability of the lipid membrane or by an environment that is not sufficiently crowded. Another promising alternative to lipid-based protocellular micro-compartments are proteinosomes, which are delineated by a semi-permeable, enzymatically active membrane consisting of protein-polymer nano-conjugates. In this work, we demonstrate the versatility of such proteinosomes as multi-functional protocellular micro-compartments. The enzyme-polymer membrane functions as an integral part of a multi-enzyme pathway, facilitating the production of a natural inducer which subsequently initiates fluorescent protein expression from an in vitro transcription-translation system encapsulated within the artificial cell.