nitrobacteraceae nitrobacteraceae the nitrobacteraceae are a family of gram-negative, aerobic bacteria. they include plant-associated bacteria such as bradyrhizobium, a genus of rhizobia associated with some legumes. it also contains animal-associated bacteria such as afipia felis, formerly thought to cause cat-scratch disease. others are free-living, such as rhodopseudomonas, a purple bacterium found in marine water and soils. the strain rhodopseudomonas palustris dx-1 can generate an electric current with no hydrogen production, a trait being explored in the development of the microbial fuel cell. the genus afipia has also been found in the atmosphere, where it uses methylsulfonylmethane as a carbon source. nitrobacteraceae scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: hyphomicrobiales family: nitrobacteraceaecorrig. buchanan 1917 (approved lists 1980) genera afipia brenner et al. 1992 blastobacter zavarzin 1961 (approved lists 1980) bradyrhizobium jordan 1982 nitrobacter winogradsky 1892 (approved lists 1980) pseudolabrys kämpfer et al. 2006 pseudorhodoplanes tirandaz et al. 2015 rhodoplanes hiraishi and ueda 1994 rhodopseudomonas czurda and maresch 1937 (approved lists 1980) tardiphaga de meyer et al. 2012 variibacter kim et al. 2014 synonyms nitrobacteriaceae buchanan 1917 (approved lists 1980) bradyrhizobiaceae garrity et al. 2006 the bacteria of this family derive their energy from oxidizing ammonia to nitrite, or by oxidizing nitrite to nitrate. they are commonly found in freshwater and soil. phylogeny the currently accepted taxonomy is based on the list of prokaryotic names with standing in nomenclature (lpsn). the phylogeny is based on whole-genome analysis. nitrobacteraceae variibacter pseudorhodoplanes pseudolabrys afipia rhodopseudomonas bradyrhizobium outgroup phreatobacteraceae