Figure 4.

Some macromolecules used in experimental approaches to the synthesis of protocells based on vesicles as containers. (a,b) Two views of the α-hemolysin pore protein are shown. It has been used as a membrane channel to create selective permeability conditions in phospholipid vesicles. (c) The ATP synthase enzyme, spontaneously incorporated to liposome membranes and able to pump protons inside them, thus allowing a simple metabolism to be maintained. (d) The T7 RNA polymerase structure is shown, with a small piece of the DNA chain also indicated.