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Updated: Jun 12, 2026
08:03
Heuristic Mining of Hierarchical Genotypes and Accessory Genome Loci in Bacterial Populations
Published on: December 7, 2021
Gene ancestries reveal diverse microbial associations during eukaryogenesis
Moisès Bernabeu1,2, Saioa Manzano-Morales1,2, Marina Marcet-Houben1,2,3
1Barcelona Supercomputing Centre (BSC), Plaça Eusebi Güell, Barcelona, Spain.
Nature
|June 10, 2026
Summary
The origin of eukaryotes involved complex microbial ecosystems. Multiple bacterial gene transfers, potentially aided by viruses, shaped early life before the last eukaryotic common ancestor (LECA).
Area of Science:
- Evolutionary Biology
- Genomics
- Microbiology
Background:
- The origin of eukaryotes is a major biological puzzle.
- A symbiosis between an alphaproteobacterium and an Asgard archaeon is key, but other partners and viral roles are debated.
Purpose of the Study:
- To investigate the roles of additional bacterial partners and viruses in eukaryotic origins.
- To reconstruct the proteome of the last eukaryotic common ancestor (LECA) and trace gene origins.
Main Methods:
- Utilized advanced phylogenomic approaches.
- Analyzed comprehensive datasets of cellular life and viruses.
- Performed phylogenetic analysis to trace protein family origins.
Main Results:
- Provided a revised reconstruction of the LECA proteome.
- Found evidence for multiple horizontal gene transfer (HGT) waves from diverse bacteria, predating mitochondrial endosymbiosis.
- Inferred traits of major bacterial donors and their functional contributions.
- Suggested a facilitating role for Nucleocytoviricota viruses.
Conclusions:
- HGT significantly shaped pre-LECA proteomes.
- Eukaryotic origins likely occurred in complex microbial ecosystems through diverse associations.
- Viral interactions may have played a role in facilitating eukaryotic evolution.
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