In the three domains of life, there is a great diversity of metabolisms. This diversity is the consequence of multiple evolutionary events, linked to changes in the ecological niches and constrained by the ancestral metabolic network topology. Methanogenesis, one of the most ancient pathways in Archaea, represents a particularly suitable model pathway for the analysis of dynamics of metabolism. Although being very ancient and central in metabolism, it has been lost several times during the diversification of Archaea. Due to the place occupied by the methanogenesis, it is thought that its loss has induced a drastic reshuffle of the central metabolism, such as losses of ancient metabolic blocks associated to methanogenesis (MBAM), acquisitions of alternative enzymes to methanogenesis and MBAM, and substantial modifications of related enzymes.
The aim of my research is to identify the key events of MBAM losses that have profoundly influenced the evolution of Archaea, using comparative genomics and phylogenomics. This work also holds potential for biotechnological advancements, particularly through the discovery of novel enzymes. Furthermore, it will provide critical insights into the dynamics of metabolism at the scale of an entire domain of life and reveal the evolutionary constraints tied to the structure of metabolic networks. This enhanced understanding will shed light on the physiology of the earliest living organisms.
MBAM Schematics (Credits: Pierre GARCIA)
