In 2001, Szostak, Bartel, and Luisi proposed a concept of “protocell” that is composed of lipid bilayer membrane and capable to evolve and continue metabolism. Eighteen years have passed since then, with the development of various technologies, the protocell has come just before the realization. The protocell is a chemical model that elaborately imitates the dynamics of living cells in a constitutive approach. In order to understand these studies, especially for graduate students and researchers from other fields, we classify chemical models of cell–sized closed lipid bilayer membrane (giant vesicle) in eight directions and discuss them here: preparation of giant vesicles, encapsulation of DNA/RNA, introduction of membrane proteins, install of cell division mechanics, self–reproduction, functionalization for motility, signal communication, and recurrent cycle of mutation and selection.
