Thanks, Jonathan. I never knew him but I won't forget him, either. Thanks for the link!
"The branched and reticulate phytanyl tails and the lipid monolayers all seem to be adaptations to scalding temperatures."
To predict the domain diversification I find it helpful to contrast Valentine's energy theory on archaea with Lane's energy theory on eukaryotes.
Lane puts eukaryotes as high energy density specialists having access to ~ 10^5 the energy density of bacteria by way of mitochondria specialized genomes energy plants. Several ecological niche inventions follows.
Valentine puts archaeas as low energy density specialists by way of low ion leakage membranes and small genomes. They naturally separate out from bacteria in almost all ecological niches, by temperature but also other characteristics like salinity et cetera.
I therefore assumed that the absence of parasitism in the form of other specialization (life cycles and what not) could be predicted by the generic niche pressure of minimizing genomes.
By exclusion, bacterias finds their niches as medium energy generalists.
Tracing membrane metabolism phylogenetically it looks like the DNA UCA was a non-chiral lipid generalist. With 50 % chance of choosing each chirality as niche specialization happened, I think the resulting 2-1 result is reasonable.
"No one really knows, although some have guesses."
Well and good, but mind that astrobiology texts (which is my interest) lists a lot of similar mechanisms.
"experiments suggest there may be archaeal species that can tolerate temperatures of 140 to 150C. Lest you forget, water boils at 100C."
Mind that these life forms live at ocean pressures where such hot water doesn't boil. So it is continuous with earlier cellular lifestyles.
But, 140-150 degC!? That is a teaser, and no references given! No papers yet?
As for histones, it seems to this layman that persistent DNA binding proteins are legion. "Histone-like" proteins are found in bacteria and viruses alike: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3326515/ .
If bacteria dumped their ancestral histones, it wouldn't be unprecedented. I hear that the reason insects Hox organization is so peculiar is that they, like generic bacteria, rushes their development. It is perhaps more "Hox-like" than Hox proper, as they do everything 'at once'.
This post is epic Jennifer! Enjoyed it like a good novel.
Great overview of Archaea, Jennifer, thanks! And a nice tribute to Woese. I wonder ... are misnomers common, left over from more ignorant times? I checked the Haloquadratum link and found they are members of the "Halobacteriaceae".
I have read the above facts and they are truely amazing but I have a query to be solved that why are "postage stamp like sheets of cell" of archaea found in red sea?
I am hoping for a quick reply to this.
Wonderful tribute. I have been compiling other tributes and related information about Woese here: http://phylogenomics.blogspot.com/2012/12/rip-carl-woese-collecting-posts-notes.html