Protein synthesis in liposomes with a minimal set enzymes …

Luisi, 2007Protein synthesis in liposomes with a minimal set of enzymes.

Protein synthesis in liposomes with a minimal set of enzymes

Cell-free protein synthesis is becoming a powerful technique to construct and to study complex informational processes . Engineering synthetic gene circuits in a test tube, however, is seriously limited by the transcription repertoire of modern cell-free systems, composed of only a few bacteriophage regulatory elements. Here, we report the construction and the phenomenological characterization of synthetic gene circuits engineered with a cell-free expression toolbox that works with the seven sigma factors. The endogenous holoenzyme E70 is used as the primary transcription machinery. Elementary circuit motifs, such as multiple stage cascades, AND gate and negative feedback loops are constructed with the six other sigma factors, two bacteriophage RNA polymerases, and a set of repressors. The circuit dynamics reveal the importance of the global mRNA turnover rate and of passive competition-induced transcriptional regulation. Cell-free reactions can be carried out over long periods of time with a small-scale dialysis reactor or in phospholipid vesicles, an artificial cell system. This toolbox is a unique platform to study complex transcription/translation-based biochemical systems .

Protein synthesis in liposomes with a minimal set of enzymes.

To avoid the problem of low enzyme production yields, liposomes were recently fed with newly synthesized proteins and lipid precursors from the outside. However, also in this case phospholipid formation was inefficient and the claimed membrane growth of

Protein synthesis in liposomes with a minimal set of enzymes.
Giovanni Murtas, Yutetsu Kuruma, Paolo Bianchini, Alberto Diaspro and Pier Luigi Luisi,
Biochemical and Biophysical Research Communications 2007, 363, 12-17.