Branching order of bacterial phyla (Woese, 1987)

For the same tree with newly discovered phyla, see Branching order of bacterial phyla (Rappe and Giovanoni, 2003).

Main article: Bacterial phyla

There are several models of the Branching order of bacterial phyla, one of these was proposed in 1987 paper by Carl Woese.

The branching order proposed by Carl Woese was based on molecular phylogeny, which was considered revolutionary as all preceding models were based on discussions of morphology. (v. Monera). Several models have been proposed since and no consensus is reached at present as to the branching order of the major bacterial lineages.

The gene used was the 16S ribosomal DNA.

Tree

The names have been changed to reflect more current nomenclature used by molecular phylogenists.

	Archaea + eukaryote
Bacteria	Thermotogae Chloroflexi Deinococcus-Thermus Proteobacteria Cyanobacteria Firmicutes Actinobacteria Planctomycetes Chlamydiae Spirochaetes Bacteroidetes Chlorobi

Note on names

See also: Bacterial taxonomy

Despite the impact of the paper on bacterial classification, it was not a proposal for change of taxonomy. Consequently, many clades were given official names. Only subsequently, this occurred: for example, the "purple bacteria and relatives" were renamed Proteobacteria.

Last universal common ancestor

Main article: Last universal common ancestor

The root of the tree, i.e. the node of the last universal common ancestor, is placed between the domain Bacteria (or kingdom Eubacteria as it was then known) and the clade formed by the domains Archaea (formerly kingdom Archaebacteria) and Eukaryotes. This is consistent with all subsequent studies, bar the study by Thomas Cavalier-Smith in 2002 and 2004, which was not based on molecular phylogeny.

Eukaryotes are a mosaic of different lineages:

• The genome in the nucleus descends from the first organelle-less eukaryote, the "urkaryote" a sister species to the ancestral archeon
• The mitochondria are organelles that descended from the proto-mitochondrion, a species of Rickettsiales (Alphaproteobacteria) (v. Reclinomonas and retortamonads).
• The chloroplasts are organelles of cyanobacterial origin.

Consequently, in Woese (1987) the group is referred to as urkaryote.

The clade composed of Archaea and the nuclear genome of eukaryotes is called Neomura by T. Cavalier-Smith

See also

• Branching order of bacterial phyla (Woese, 1987)
• Branching order of bacterial phyla (Rappe and Giovanoni, 2003)
• Branching order of bacterial phyla after ARB Silva Living Tree
• Branching order of bacterial phyla (Ciccarelli et al., 2006)
• Branching order of bacterial phyla (Battistuzzi et al.,2004)
• Branching order of bacterial phyla (Gupta, 2001)
• Branching order of bacterial phyla (Cavalier-Smith, 2002)