Roseburia hominis is a bacterium first isolated from human feces. It is anaerobic, Gram-negative or Gram-variable, slightly curved rod-shaped and motile. The cells range in size from 0.5-1.5 to 5.0 μm. A2-183(T) (=DSM 16839(T)=NCIMB 14029(T)) is the type strain. It is being studied as a potential treatment for ulcerative colitis in pediatric patients ages 0 through 16 years.