Arranging the polymers by their structure in an evolutionary tree is a deceiving approach: for DNA, it doesn't reflect the introns/exons issues, nor the post-translational modifications; for proteins, it doesn't hit upon the existence of iso(alo)enzymes.
How to build such a tree? Using solely RNA is not a a solution either, for the same reasons; probably best is to have 3 different trees, for RNA, DNA and AAA (proteins), that must overlap for a particular metabolic feat (like a single metabolic change - 1 bit), and then create hyper trees for a metabolic path, a metabolic chain and further on, networks.
It is interesting to speculate on the metabolism of organisms such as M. genitarium (or better yet, M. laboratorium) and the minimum of metabolic reactions necessary to sustain/replicate life. It is certainly enticing to envision such a system as the precursor of at current unicellular beings. Even a replicator, as suggested by Eigen, ought to have a branched phylogenetic tree.
http://www.nytimes.com/2009/02/10/science/10tree.html?ex=1391922000&en=7f8374c58013a4f5&ei=5124&partner=digg&exprod=digg ( spur of the moment)
http://biology.plosjournals.org/archive/1545-7885/6/1/pdf/10.1371_journal.pbio.0060018-L.pdf (Orgel's last thoughts on the issue)
e Ai
How to build such a tree? Using solely RNA is not a a solution either, for the same reasons; probably best is to have 3 different trees, for RNA, DNA and AAA (proteins), that must overlap for a particular metabolic feat (like a single metabolic change - 1 bit), and then create hyper trees for a metabolic path, a metabolic chain and further on, networks.
It is interesting to speculate on the metabolism of organisms such as M. genitarium (or better yet, M. laboratorium) and the minimum of metabolic reactions necessary to sustain/replicate life. It is certainly enticing to envision such a system as the precursor of at current unicellular beings. Even a replicator, as suggested by Eigen, ought to have a branched phylogenetic tree.
http://www.nytimes.com/2009/02/10/science/10tree.html?ex=1391922000&en=7f8374c58013a4f5&ei=5124&partner=digg&exprod=digg ( spur of the moment)
http://biology.plosjournals.org/archive/1545-7885/6/1/pdf/10.1371_journal.pbio.0060018-L.pdf (Orgel's last thoughts on the issue)
e Ai
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