Giant vesicles as microreactors for enzymatic mRNA synthesis.

Giant vesicles have attracted much attention as possible microreactors for the conduction of enzymatic reactions in an artificial, cell-sized compartment. In this context, we demonstrated in the first part of the present work that giant vesicles formed from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine in an alternating electric field can be made more permeable to Ca(2+) ions or nucleotide triphosphates by addition of ethanol. This methodology is then applied in a second step whereby these giant vesicles are used as microreactors in which mRNA synthesis can occur. The macromolecules (the DNA template and the enzyme T7 RNA polymerase) are microinjected into a selected giant vesicle, while the substrate molecules (nucleotide triphosphates) are added from the external medium. The fact that mRNA synthesis can be detected is a further step towards our aim: the design of a microreactor that can be seen as a model for a protocell.