Bottom–up protocell design: Gaining insights in the emergence of complex functions

Abstract

All contemporary living cells are a collection of self-assembled molecular elements that by themselves are non-living but through the creation of a network exhibit the emergent properties of self-maintenance, self-reproduction, and evolution. Protocells are chemical systems that should mimic cell behavior and their emergent properties through the interactions of their components. For a functional protocell designed bottom-up, three fundamental elements are required: a compartment, a reaction network, and an information system. Even if the functions of protocell components are very simplified compared to those of modern cells, realizing a system with true inter-connection and inter-dependence of all the functions should lead to emergent properties. However, none of the currently studied systems have yet reached the threshold level necessary to be considered alive. This chapter will discuss the on-going research that aims at creating artificial cells assembled from a collection of smaller components, i.e., protocell systems from bottom-up designs.