Originally developed to decipher the genetic code and study gene regulation, cell-free transcription-translation (TX-TL) systems are becoming powerful platforms to construct biological systems in vitro through the expression of synthetic gene circuits. In the past decade, considerable efforts have been made to expand the capabilities of these systems that can be used as quantitative chassis for biophysics and biochemistry.
My lab has developed an all E. coli cell-free TX-TL system to prototype gene networks in vitro. Recently we have shown that entire phages can be synthesized in cell-free TX-TL reactions from their genomes. The bacteriophage T7, composed of about 60 genes, is entirely synthesized in a single test tube reaction from its 40 kbp genomic DNA. Replication of the phage genome occurs concurrently with phage expression and DNA packaging. Cell-free synthesis of T7 is a model system to characterize the relationship information-self-assembly as well as to quantify biophysical aspects such as molecular crowding. Encapsulated inside cell-sized phospholipid liposomes, the TX-TL system is used to construct a minimal cell using a bottom-up approach. I will present this cell-free biology platform and our last experiments.