RT Journal Article
SR Electronic
T1 The sunlit microoxic niche of the archaeal eukaryotic ancestor comes to light
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 385732
DO 10.1101/385732
A1 Paul-Adrian Bulzu
A1 Adrian-Ştefan Andrei
A1 Michaela M. Salcher
A1 Maliheh Mehrshad
A1 Keiichi Inoue
A1 Hideki Kandori
A1 Oded Beja
A1 Rohit Ghai
A1 Horia L. Banciu
YR 2018
UL http://biorxiv.org/content/early/2018/08/06/385732.abstract
AB The discovery of Asgardaeota archaea, the closest extant relative of eukaryotes to date, has reignited the two-domain of life theory. While it is apparent that Asgardaeota encode multiple eukaryotic-specific proteins, the lack of genomic information and metabolic characterization has precluded inferences about the closest eukaryotic ancestor and the metabolic landscape that laid the grounds for the emergence of the hallmark eukaryotic subcellular architecture. Here, we propose that Heimdallarchaeia (phylum within Asgardaeota) are the closest extant relatives to all eukaryotes and shed light on their facultative aerobic lifestyle, characterized by the capacity to use Sun’s energy and aerobic metabolic pathways unique among archaea. Remarkably, the visualization of Heimdallarchaeia organisms revealed a compacted genetic material that is highly unusual for prokaryotes at large. Our results support an evolutionary model in which both protoeukaryote ancestors (archaeal and bacterial) possessed the metabolic repertoire for oxygenic respiration and point towards a late mitochondrial acquisition.