Here are some good links on the subject:
My Name is LUCA -- The Last Universal Common Ancestor:
http://www.actionbioscience.org/newfrontiers/poolepaper.html
What is the Last Universal Common Ancestor:
http://www.actionbioscience.org/...ontiers/poolearticle.html
Were Bacteria the First Forms of Life on Earth?:
http://www.actionbioscience.org/...tiers/jeffares_poole.html
and this paper traces the origin of all RNA metabolism back to LUCA:
Comparative genomics and evolution of proteins involved in RNA metabolism. Anantharaman V, Koonin EV, Aravind L. Nucleic Acids Res 2002 Apr 1;30(7):1427-64. PMID: 11917006
maybe it deserves its own thread in the origin of life forum?
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