Members of Flavobacterium are ubiquitous organisms that can cause infection in premature infants and immunocompromised individuals. They are not difficult to distinguish from other nonfermenters because most species produce indole when grown in tryptophan broth. While most species of Flavobacterium metabolize glucose oxidatively, some have been shown to be really slow fermenters. In any case, all species are motile and oxidase positive. The species most often recovered from humans is F. meningosepticum, a penicillin resistant bacterium that can cause neonatal meningitis. Vancomycin is usually effective in Flavobacterium infection.
All the species in this genus are oxidase positive, motile, and can grow on MacConkey agar. The most coommon species A. faecalis, an opportunistic pathogen which usually inhabits soil and water. This organism has a characteristic fruity odor which distinguishes it from other Alcaligenes species.