Activation of a diluted E. coli cell-free transcription-translation system within liposomes by hypertonic concentration.

We present a protocol for activating protein synthesis in liposomes encapsulating a diluted E. coli cell extract-based TX-TL (transcription-translation) system by hypertonic concentration. Protein expression is turned on in the liposome-encapsulated TX-TL system by simple treatment with a concentrated external solution. The expression of sfGFP is demonstrated here, but it can be applied to other proteins. This protocol can be applied to the development of artificial cells utilizing the switch-on mechanism to activate protein expression, responding to the outer environment. For complete details on the use and execution of this protocol, please refer to Akui et al. (2021).

Transcription-translation of the Escherichia coli genome within artificial cells.

Here we created artificial cells in which information of the genome of living cells is expressed by the elements encoded in the genome. We confirmed that the system works normally within artificial cells, which paves the way for reconstructing living cells from biomolecules.