caulobacterales caulobacterales caulobacterales is an order of gram-negative pseudomonadota within the alpha subgroup. caulobacterales caulobacter crescentus scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: caulobacteraleshenrici and johnson 1935 (approved lists 1980) families caulobacteraceae henrici and johnson 1935 (approved lists 1980) hyphomonadaceae lee et al. 2005 maricaulaceae kevbrin et al. 2021 genera incertae sedis "chamaesiphonosira" geitler 1975 "hyphobacter" nikitin et al. 1990 synonyms maricaulales kevbrin et al. 2021 hyphomonadales kevbrin et al. 2021 "candidatus viadribacter manganicus" braun and szewzyk 2016