Nikola Zlatkov Kolev
Department of Molecular Biology
Umea University, Sweden

AND

Medical University of Vienna
Department of Pathology
Prof. DDr. Kenner's Group

Program

"Evolutionary dynamics on contemporary timescales and the impact of micronanoplastics"

Bacterial eco-evolutionary dynamics are driven either by natural selection or key innovations, which can be induced by spontaneous mutations and novel ecological conditions. 

The mechanisms behind key innovations (complex evolutionary events) and whether they may result from contemporary evolutionary processes remain uncertain. Escherichia coli is among the bacterial species exhibiting the greatest diversity of ecovars, indicating significant eco-evolutionary mechanisms at play. In this talk, I argue that the B2 E. coli ecovars are genetically isolated from the main phylogroup A to a degree that correlates with their sequence divergence rather than with their habitat. I give examples of how nutritional stress triggers contemporary key innovation events in the B2 group, linked to the use of citrate—one of the forbidden phenotypes of this species. I correlate the fitness of the evolved strains to the effects of host environments, such as blood, urine, and cerebrospinal fluid, and show that they have opposite effects on the regulation of the gene flow. In the end, I speculate how the use of citrate can be linked to atypical pathogenicity.

Nevertheless, ecology encompasses any combination of biotic and abiotic factors that can exert selective pressure. Although plastic pollution's effects are generally acknowledged as a global concern, little is known about the molecular activities of nanoplastics (NPs) as a novel environmental factor. I also present preliminary data on the mutagenic potential of selected polystyrene and polymethyl methacrylate NPs on bacteria. Being the constant feature of life due to the bacteria's small size, short generation time, and enormous adaptive and metabolic potential, bacteria are a good test subject for interactions with NPs. Here, I provide some examples of interaction between NPs and the bacterial cell wall as well as of mutagenic and adaptive events resulting from NP interactions with the bacterial genome.
 

Host: Ulrike RESCH

Contact for questions: Helmut KUBISTA