rubribacterium rubribacterium rubribacterium is an alkaliphilic genus of bacteria from the family of rhodobacteraceae. rubribacterium polymorphum has been isolated from a siberian soda lake. rubribacterium scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: rhodobacterales family: rhodobacteraceae genus: rubribacteriumboldareva et al. 2010 type species rubribacterium polymorphum species r. polymorphum