Figure 2

Schematic representation of the phylogenetic tree for most of the organisms used in this analysis. The tree was redrawn from Gough et al [35] using Drawgram from the Phylip package http://evolution.genetics.washington.edu/phylip.html. Eukaryotes: Homo sapiens, Caenorhabditis elegans, Drosophila melanogaster, Saccharomyces cerevisiae, Arabidopsis thaliana, archaea: Aeropyrum pernix, Sulfolobus solfataricus, Thermoplasma volcanium, Thermoplasma acidophilum, Methanopyrus kandleri, Methanococcus jannaschii, Methanobacterium thermoautotrophicum, Archaeoglobus fulgidus, Pyrococcus abyssi, Pyrococcus horikoshii, Halobacterium sp. and bacteria: Campylobacter jejuni; Thermatogales: Thermotoga maritima; Parasitic proteobacteria: Rickettsia conorii, Rickettsia prowazekii, Buchnera aphidicola; Chlamydiae: Chlamydophila pneumoniae, Chlamydia trachomatis; Spirochetes: Borrelia burgdorferi, Treponema pallidum; Mycoplasmas: Mycoplasma genitalium, Mycoplasma pneumoniae, Ureaplasma urealyticum, Mycoplasma pulmonis; Bacillus/Clostridium-group: Caulobacter crescentus, Staphylococcus aureus, Bacillus halodurans, Bacillus subtilis, Lactococcus lactis, Streptococcus pneumoniae, Streptococcus pyogenes, Clostridium acetobutylicum; Cyanobacteria: Nostoc sp., Synechocystis sp.; Thermus/Deinococcus-group: Deinococcus radiodurans; Actinobacteria: Mycobacterium tuberculosis CDC1551, Mycobacterium tuberculosis H37Rv, Mycobacterium leprae; free-living α-proteobacteria: Agrobacterium tumefaciens, Mesorhizobium loti, Sinorhizobium meliloti; ε-proteobacteria: Helicobacter pylori-J99, Helicobacter pylori-26695; Aquificales: Aquifex aeolicus and βγ-proteobacteria: Escherichia coli:0157:H7, Escherichia coli:0157:H7:EDL933, Escherichia coli:k-12, Salmonella typhimurium, Yersinia pestis, Vibrio cholerae, Neisseria meningitidis 72491, Neisseria meningitidis MC58, Xylella fastidiosa, Pseudomonas aeruginosa, Ralstonia solanacearum, Pasteurella multocida, Haemophilus influenzae. Furthermore, 6 additional eukaryotes (Schizosaccharomyces pombe, Plasmodium falciparum, Encephalitozoon cuniculi, Mus musculus, Rattus norvegicus, Danio rerio) and 6 additional archaea (Methanosarcina mazei, Methanosarcina acetivorans, Nanoarchaeum equitans, Pyrobaculum aerophilum, Pyrococcus furiosus, Sulfolobus tokodaii) were used in the analysis.