abortus – Brucella canis – Brucella melitensis – Brucella ovis – Brucella suis – Ochrobactrum – Ochrobactrum anthropi – Caulobacteraceae – Caulobacter – Caulobacter crescentus – Holosporaceae – hyphomicrobiaceae – Azorhizobium – Azorhizobium caulinodans – Hyphomicrobium – Rhodomicrobium – Xanthobacter – methylobacteriaceae – Methylobacterium – Methylobacterium extorquens – Methylocystaceae – Methylosinus – Methylosinus trichosporium – Rhodospirillales – acetobacteraceae – Acetobacter – Acidiphilium – Gluconacetobacter – Gluconacetobacter xylinus – Gluconobacter – Gluconobacter oxydans – Rhodospirillaceae – Azospirillum – Azospirillum brasilense – Azospirillum lipoferum – Magnetospirillum – Rhodospirillum – Rhodospirillum centenum – Rhodospirillum rubrum – rhizobiaceae – Rhizobium – Rhizobium etli – Rhizobium leguminosarum – Rhizobium phaseoli – Rhizobium radiobacter – Rhizobium tropici – Sinorhizobium – Sinorhizobium fredii – Sinorhizobium meliloti – Rhodobacteraceae – Paracoccus – Paracoccus denitrificans – Paracoccus pantotrophus – Rhodobacter – Rhodobacter capsulatus – Rhodobacter sphaeroides – Rhodovulum – Roseobacter – rickettsiaceae – rickettsieae – Orientia tsutsugamushi – Rickettsia – Rickettsia akari – Rickettsia conorii – Rickettsia felis – Rickettsia prowazekii – Rickettsia rickettsii – Rickettsia typhi – Wolbachia – sphingomonadaceae – Sphingomonas – Zymomonas – Betaproteobacteria – alcaligenaceae – Achromobacter – Achromobacter cycloclastes – Achromobacter denitrificans – Alcaligenes – Alcaligenes faecalis – Bordetella – Bordetella avium – Bordetella bronchiseptica – Bordetella parapertussis – Bordetella pertussis – Taylorella – Taylorella equigenitalis – burkholderiaceae – Burkholderia – Burkholderia cepacia complex – Burkholderia cepacia – Burkholderia gladioli – Burkholderia mallei – Burkholderia pseudomallei – comamonadaceae – Comamonas – Comamonas testosteroni – Delftia – Delftia acidovorans – Leptothrix – Sphaerotilus – gallionellaceae – hydrogenophilaceae – Thiobacillus – methylophilaceae – Methylobacillus – Methylophilus – Methylophilus methylotrophus – neisseriaceae – Chromobacterium – Eikenella – Eikenella corrodens – Kingella – Kingella kingae – Neisseria – Neisseria cinerea – Neisseria elongata – Neisseria gonorrhoeae – Neisseria lactamica – Neisseria meningitidis – Neisseria meningitidis, serogroup A – Neisseria meningitidis, serogroup B – Neisseria meningitidis, serogroup C – Neisseria meningitidis, serogroup W-135 – Neisseria meningitidis, serogroup Y – Neisseria mucosa – Neisseria sicca – Vitreoscilla – nitrosomonadaceae – Nitrosomonas – Nitrosomonas europaea – oxalobacteraceae – Herbaspirillum – Oxalobacter formigenes – ralstoniaceae – Ralstonia – Ralstonia pickettii – Ralstonia solanacearum – Wautersia – Wautersia eutropha – rhodocyclaceae – Azoarcus – Thauera – Zoogloea – Spirillaceae – Spirillum – Deltaproteobacteria NOTE: The class Deltaproteobacteria has been dismantled and its members have been assigned to new phyla (indicated in parentheses). – Bdellovibrio (Bdellovibrionota) – Bilophila (Thermodesulfobacteriota) – Desulfovibrio (Thermodesulfobacteriota) – Desulfovibrio