Procabacter (sic) Horn et al. 2002 Procaibacter corrig. Horn et al. 2002 Procaibacter acanthamoebae corrig. Horn et al. 2002 Procabacter acanthamoebae (sic) Horn et al. 2002 Universal Root Woese et al. 1990 Bacteria (None 2015) Woese et al. 1990 Proteobacteria (sic) Garrity et al. 2021 Pseudomonadota corrig. Garrity et al. 2021 Alphaproteobacteriota (sic) Garrity et al. 2021 Betaproteobacteria Garrity et al. 2006 emend. Boden et al. 2017 Procabacteriales (sic) Garrity et al. 2003 Procaibacteriales corrig. Garrity et al. 2003 Procabacteriaceae (sic) Garrity et al. 2003 Procaibacteriaceae corrig. Garrity et al. 2003 Procabacter (sic) Horn et al. 2002 Procaibacter corrig. Horn et al. 2002 Procabacteriaceae (sic) Garrity et al. 2003 Procaibacteriaceae corrig. Garrity et al. 2003 Procaibacter acanthamoebae corrig. Horn et al. 2002 Procabacter acanthamoebae (sic) Horn et al. 2002 Garrity G.M. Bell J.A. Lilburn T. Garrity G.M. Bell J.A. Lilburn T.G. Taxonomic outline of the Procaryotes 2003 4 1 39 Taxonomic Outline of the Procaryotes, Bergey's Manual of Systematic Bacteriology, Second Edition. Release 4.0 Springer-Verlag New York 10.1007/bergeysoutline200310 Horn M. Fritsche T.R. Linner T. Gautom R.K. Harzenetter M.D. Wagner M. Obligate bacterial endosymbionts of Acanthamoeba spp. related to the beta-Proteobacteria: proposal of 'Candidatus Procabacter acanthamoebae' gen. nov., sp. nov. 2002 52 2 599 605 International Journal of Systematic and Evolutionary Microbiology Int J Syst Evol Microbiol 1466-5026 1466-5034 10.1099/ijs.0.01970-0 11931173