MBE Advance Access originally published online on November 13, 2007
Molecular Biology and Evolution 2008 25(1):1-4; doi:10.1093/molbev/msm249
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Letter |
Evidence Excluding the Root of the Tree of Life from the Actinobacteria


,
,
,
,1
* Molecular Biology Institute, University of California, Los Angeles
UCLA Astrobiology Institute, University of California, Los Angeles
Department of Molecular, Cellular, and Developmental Biology, University of California, Los Angeles
Department of Human Genetics, University of California, Los Angeles
E-mail: lake{at}mbi.ucla.edu.
Accepted for publication November 8, 2007.
The Actinobacteria are found in aquatic and terrestrial habitats throughout the world and are among the most morphologically varied prokaryotes. They manufacture unusual compounds, utilize novel metabolic pathways, and contain unique genes. This diversity may suggest that the root of the tree of life could be within the Actinobacteria, although there is little or no convincing evidence for such a root. Here, using gene insertions and deletions found in the DNA gyrase, GyrA, and in the paralogous DNA topoisomerase, ParC, we present evidence that the root of life is outside the Actinobacteria.
Key Words: tree of life root indels cenancestor Actinobacteria prokaryotes
1 Present address: 232 Boyer Hall, 611 South Young Drive, University of California, Los Angeles.