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 stat. inval.
     Kingdom Bacteria Cavalier-Smith 1998 nom. inval. - bacteria see Kingdom Bacteria Cavalier-Smith 2002 stat. inval.
       Subkingdom Eubacteria Cavalier-Smith 1981 see Domain Bacteria Woese et al. 1990 stat. inval.
         Division Gracilicutes Gibbons and Murray 1978 (Approved Lists 1980) see Phylum Gracilicutes
           Phylum Proteobacteria Garrity and Holt 2001 nom. nud. see Phylum Proteobacteria Garrity et al. 2005 stat. inval.
             "Gamma Group" see Class Gammaproteobacteria Garrity et al. 2005
               1 "Enterics" see Class Gammaproteobacteria "Garrity and Holt 2001" nom. nud.
               2 Genus Azotobacter Beijerinck 1901 (Approved Lists 1980)
               3 Genus Beggiatoa Trevisan 1842 nom. cons. (Approved Lists 1980)
               4 Genus Chromatium Perty 1852 (Approved Lists 1980)
               5 Genus Legionella Brenner et al. 1979 (Approved Lists 1980)
               6 Genus Leucothrix Örsted 1844 (Approved Lists 1980)
               8 Genus Thiocapsa Winogradsky 1888 (Approved Lists 1980)
               9 Genus Thiospirillum Winogradsky 1888 (Approved Lists 1980)