Exploring ‘minimal metabolism’ as a central concept for understanding the origins of life and developing systems biology

Abstract

Origins of life (OL) research, as the name suggests, is concerned with the question of how cellular organisms could have develop, starting from complex chemical reaction systems, i.e.the transition from geo-chemistry to bio-chemistry. This vast and interdisciplinary research field has been dominated for many years by rather reductionistic approaches, that were mainly searching for a primordial type of biopolymer. However, in recent years, a shift towards a more systems oriented view of life and its origins has taken place, spurred by the emergence of fields like `systems biology' and `systems chemistry'. Rather than focusing on a single type of biomolecule or biochemical reaction pathway, these new approaches target the way in which molecular components and transformation processes are organized within biological (and proto-biological) systems. On these lines, the motivation behind this dissertation is to introduce the idea of `minimal metabolism' (MM) as a heuristic construct that lies at the interface between chemistry and biology. So this theoretical proposal should not be taken as a final or complete characterization of metabolism, but as a particular contemporary way of thinkingabout it to encourage further research. With that aim, an attempt is made at modelling such aminimal metabolic system. This is achieved through the implementation of two different types of computational models, each focusing on a certain aspect associated with MM. The results of these two modelling approaches are then compared and critically discussed. Finally, a general outlook and perspective for future research on MM, and OL in general, is given.