Complex patterns predicted in an in vitro experimental model system for the evolution of molecular cooperation

An isothermal biochemical in vitro amplification system with two trans-cooperatively coupled amplifying DNA molecules was investigated homogeneously using a hierarchy of kinetic models and as a simplified reaction diffusion system. In our model of this recently developed experimental system, no reaction mechanism higher than second order occurs, yet numerical simulations show a variety of complex spatiotemporal patterns which arise in response to finite amplitude perturbations in a flow reactor. In a certain domain of the kinetic parameters the system shows self-replicating spots. These spots can stabilize the cooperative amplification in such evolving systems against emerging parasites. The results are of high relevance for experimental studies on these functional in vitro ecosystems in spatially resolved microstructured reactors.