Bioinformatics and the origin of the eukaryotic cell

Damien Devos

Date and place: Wednesday January, 27th 12:30 at 1/75 (B6c)

I will highlight the interplay between large-scale bioinformatics, experimental molecular biology, and microscopy to contribute to biologically relevant questions, in this case, the origin of the eukaryotes.

Despite decades of research, the origin of eukaryotic cells remains an unsolved issue. The endomembrane system defines the eukaryotic cell, and its origin is linked to that of eukaryotes. We used large-scale bioinformatic protein analysis to search within all known sequences for proteins that are characteristic of the eukaryotic endomembrane system, using a combination of fold types that is uniquely found in the membrane coat proteins. Outside eukaryotes, such proteins were solely found in the Planctomycetes-Verrucomicrobia-Chlamydiae (PVC) bacterial superphylum. By immuno-electron microscopy, one of these bacterial proteins was found to localize adjacent to the membranes of vesicles found within the cells of one member of the PVC superphylum. Thus, there appear to be similarities between bacterial and eukaryotic compartmentalization systems, suggesting that the bacterial PVC superphylum may have contributed significantly to eukaryogenesis.