Kingdom Bacteria Cavalier-Smith 2002 - bacteria see Domain Bacteria Woese et al. 1990 1 Subkingdom Negibacteria Cavalier-Smith 2002 - negibacteria see Domain Bacteria Woese et al. 1990 2 Subkingdom Unibacteria Cavalier-Smith 2002 see Domain Bacteria Woese et al. 1990