Lokiarchaea are close relatives of Euryarchaeota, not bridging the gap between prokaryotes and eukaryotes.

ABSTRACT: The eocyte hypothesis, in which Eukarya emerged from within Archaea, has been boosted by the description of a new candidate archaeal phylum, "Lokiarchaeota", from metagenomic data. Eukarya branch within Lokiarchaeota in a tree reconstructed from the concatenation of 36 universal proteins. However, individual phylogenies revealed that lokiarchaeal proteins sequences have different evolutionary histories. The individual markers phylogenies revealed at least two subsets of proteins, either supporting the Woese or the Eocyte tree of life. Strikingly, removal of a single protein, the elongation factor EF2, is sufficient to break the Eukaryotes-Lokiarchaea affiliation. Our analysis suggests that the three lokiarchaeal EF2 proteins have a chimeric organization that could be due to contamination a

SUBMITTER: Da Cunha V 

PROVIDER: S-EPMC5484517 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature