The Origin of Complex Cells
Van Leeuwenhoek Lecture on BioScience.
Thijs Ettema is distinguished Professor of Microbiology in Wageningen since 2019. He studied Biology in Wageningen and graduated cum laude in 2000. He obtained an MA cum laude in 2005 in Microbiology also in Wageningen. He heldThe various postdoc positions, including at Uppsala Univrsity in Sweden, where he built up a groundbreaking research group over the past 12 years in the field of microbial diversity and evolution.
At Uppsala University, Thijs Ettema was an Associate Professor in Molecular Evolution. He concentrated on mapping the large variety of micro-organisms and their evolution, with special attention to the emergence of complex cellular life. By using modern genomics strategies, such as metagenomics and single cell genomics, he has discovered countless new micro-organisms, including the "Asgard-Archeae" -micro-organisms that are descended from the ancestor from which complex life forms such as plants, animals and fungi have also arisen. He has won various prizes and research grants, included personal research grants (for more than 6 million euros devoted to research).
In his research he will focus on integrating and expanding new genomics technologies in ongoing research as well as setting up his own research group. Particular attention will be paid to developing methods to grow new, as yet unknown micro-organisms on a large scale, with the aim of studying them in detail.
The origin of the eukaryotic cell represents an enigmatic evolutionary puzzle. Ever since the discovery of the archaeal domain of life by Carl Woese and coworkers, Archaea have featured prominently in hypotheses for the origin of eukaryotes. According to Woese's "universal tree" , eukaryotes and Archeae represent sister lineages, suggesting that Archaea and Eukarya emerged from a common ancestor. Whereas the classical "Three domains" scenario has received considerable support for the so-called "Two domains" tree of life, in which eukaryotes emerged from within the archaeal domain of life. More specifically, the latest advanced phylogenomic analyses have indicated the eukaryotes form a clade with the Asgard Archeae, a diverse group of archeae that was recently discovered. Using metabologenomic analyses, several genomes of Asgard archeae lineages have been reconstructed in recent studies. Analyses of these genomes has allowed us to reconstruct the nature of the last common ancestor between archaea and eukaryotes, and infer the events that led to the symbiotic origin of the eukaryotic cell in more detail than ever before. In the present conference contribution, I wil, provide an overview of the latest work of my group, providing several new pieces of the eukaryotic puzzle.