Session September 2022: "Giant bacteria and the evolution of eukaryotes"
Talks "The role of mitochondrial energetics in the origin and diversification of eukaryotes" and "Thiomargarita magnifica, the largest bacterium ever observed is a complex macroscopic single-cell" In our September Forum on "Giant bacteria and the evolution of eukaryotic cells", Sergio Muñoz-Gómez presented theoretical predictions of feasible cell sizes for bacteria and eukaryotes, which he had recently published with our panel discussant Paul Schavemaker. Their work concerns limits on cells size that are relevant for eukaryote evolution and our understanding of the role of mitochondria (both as carriers of DNA and as a powerful source of “cheap” energy via respiration). As a concrete case that both challenges and confirms the theory, Jean-Marie Volland presented the recently discovered giant bacteria Thiomargarita magnifica, which are up to 2 centimeters long and can have 500.000 copies of their DNA. Sergio’s and Paul’s work refers to a 2010 paper “The