Source: Mike White of TrendinTech
Date: 13FEB2017
Summary: A team of scientists discovered a new archaeon that could be the closest living relative to eukaryotes. Four lineages total have been found so far that fall under the Asgardian classification (the name given to these archaea).
Connection: We’ve discussed the lineage of bacteria, archaea, and eukaryotes and how they are similar/different.
Analysis: As far as relating to a crowd unfamiliar with microbiology, I felt this article did a pretty decent job in explaining some background. They for instance give a brief description of Earth and how early Earth did not have eukaryotes, and then go into how they are and could be related. They also hypothesize that these Asgardians are a possible precursor of sorts to eukaryotes. They even provide a picture demonstrating this. It was also interesting to note that these archaea have been found all over the world, not just in a single localized area.
Question: The article did not go into great detail, but it made me curious as to what exactly these archaea in particular have in common with eukaryotes.
1 Comment for “Newly Discovered Microbes, May Explain the Origin of Complex Life”
raeastwood
says:I love how a lot of things are coming up nowadays with names relating to the Vikings. In the case of this study, however, the name is suited to the discovery of the archea they found in Loki’s castle.
In regards to your question, I found a journal article regarding Lokiarchaeota and eukaryotes. One is “Complex archaea that bridge the gap between prokaryotes and eukaryotes,” by Spang, et al. 2015. https://web.b.ebscohost.com.proxy.library.uaf.edu/ehost/pdfviewer/pdfviewer?sid=4b007911-5403-4979-acdc-9242ccf6e74e%40sessionmgr120&vid=3&hid=115d
According to the authors, phylogenomically, Lokiarchaeota are closely related to eukaryotes. Also, apparently Lokiarchaeota share signature proteins with eukaryotes. Transcription machinery and a select few core genes associated with DNA in archaea, are more closely related to eukaryotes than they are to prokaryotes. They argue that eukaryotes may have arisen from a common ancestor to archaea, or they had emerged from within the archaeal domain (Spang,et al. 2015). Analysis of data sets regarding different proteins have been incorporated into a phylogenetic tree that indicates eukaryotes came about in one of two ways, from within the archaeal domain, and as a sister taxa. There is far more information within the journal article regarding similarities between the two domains.