life see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Prokarya see Domain Bacteria Woese et al. 1990
     Kingdom Bacteria (Cohn 1870) Cavalier-Smith 1983 - bacteria see Kingdom Bacteria Cavalier-Smith 2002
       Subkingdom Eubacteria Cavalier-Smith 1981 see Domain Bacteria Woese et al. 1990
         Division Gracilicutes Gibbons and Murray 1978 (Approved Lists 1980) see Phylum Gracilicutes
           Phylum Proteobacteria Garrity and Holt 2001 see Phylum Proteobacteria Garrity et al. 2005
             "Gamma Group" see Class Gammaproteobacteria Garrity et al. 2005
               1 "Enterics" see Class Gammaproteobacteria nom. inval.
               2 Genus Azotobacter Beijerinck 1901 (Approved Lists 1980)
               3 Genus Beggiatoa Trevisan 1842 (Approved Lists 1980)
               4 Genus Chromatium Perty 1852 (Approved Lists 1980)
               5 Genus Legionella Brenner et al. 1979 (Approved Lists 1980)
               6 Genus Leucothrix Oersted 1844 (Approved Lists 1980)
               8 Genus Thiocapsa Winogradsky 1888 (Approved Lists 1980)
               9 Genus Thiospirillum Winogradsky 1888 (Approved Lists 1980)