One more proof that archaeon was derived from gram-positive bacterium
Valery Anisimov, A2iA
28 November 2012
Practically all bacteria and mostly deep lines of archaea (Korarchaeota, Thaumarchaeota) possess only
one copy of the DNA-directed RNA polymerase subunit A' (COG0086K) but all the rest of archaea's domains possess two of them (subunits A' and subunit A''), following each other. Interesting enough that most of Euryarchaeota possess also two homologs of the RNA polymerase subunit B (COG0085K), so it looks like branching order was: Gram-positive bacteria => early archaeons (Korarchaeota, Thaumarchaeota) => Crenarchaeota => Euryarchaeota.
One more proof that archaeon was derived from gram-positive bacterium
28 November 2012
Practically all bacteria and mostly deep lines of archaea (Korarchaeota, Thaumarchaeota) possess only
one copy of the DNA-directed RNA polymerase subunit A' (COG0086K) but all the rest of archaea's domains possess two of them (subunits A' and subunit A''), following each other. Interesting enough that most of Euryarchaeota possess also two homologs of the RNA polymerase subunit B (COG0085K), so it looks like branching order was: Gram-positive bacteria => early archaeons (Korarchaeota, Thaumarchaeota) => Crenarchaeota => Euryarchaeota.
Competing interests
None declared