Thursday February 29 at 18:00 in Centro Carlos Santamaria (room to be announced). The talk will be hybrid. If you want to participate, please contact amontf94@gmail.com

ABSTRACT Free-living microorganisms typically display a wide range of physiological and behavioral features, inhabiting very diverse environments where spontaneous mutations and strong selective pressure make rapid adaptation possible. The coexistence of different species and their interactions provide microbial populations with a great variety of properties and functions, broadening the space of possible phenotypes. Nevertheless, biological diversity can also be observed in less open conditions, where populations of genetically similar individuals thrive in much more homogeneous microenvironments, and still demonstrate a surprisingly high phenotypic variability. This phenomenon reflects the importance of individuality within a collective/multicellular context and has been extensively observed in different species and organizational contexts — not only in artificially cultured bacteria but also in more complex cases, like cancer cells grown in tissue. Microbial phenotypic heterogeneity manifests in different ways, including morphological changes, macromolecular composition, different growth rates, reproductive strategies, motility mechanisms or specific metabolic signatures. So far, analyses performed to study this variability have mostly focused on cell growth rates, which are not sufficient to develop a satisfactory (minimally comprehensive) interpretation of phenotypic heterogeneity.
My PhD project, which I will briefly introduce in this session, focuses on the theoretical modelling of microbial metabolisms, with the aim to compensate for this deficit: i.e., expanding the study of phenotypic diversity beyond growth rates, to include the choice of specific metabolic regimes (derived from fluxomics data analysis), which is at the basis of most additional biological processes. On these lines, a preliminary ‘conceptual map’ will be presented, where we distinguish between metabolic plasticity and metabolic heterogeneity, as properties to be ascribed, respectively, to an individual organism and to the population, which may include cross-feeding (ecological) as well as kinship (phylogenetic) relationships. In this context, the distinction between potential and actual (ontogenic, or developmental) plasticity/heterogeneity will be made, as a bridge to connect the issue with the problem of evolvability. It is important to emphasize here that phenotypic heterogeneity is an evolutionary trait and can, in turn, shape the phylogenetic trajectories within a population. Therefore, one of the main aims of my work would be to correlate phenotypic diversity (understood specifically in terms of metabolic plasticity/heterogeneity) with ecological and evolutionary aspects. Through this “eco-evo-meta” perspective, we will try to contribute to a better understanding of the role of individual organisms in the emergence of population phenotypes and its evolutionary implications at the most fundamental biological level: the microbial world.