Definition: A genus of aerobic, nonmotile bacteria (family Mycobacteriaceae) containing gram-positive, acid-fast, slender, straight or slightly curved rods; slender filaments occasionally occur, but branched forms rarely are produced. Parasitic and saprophytic species occur. Several of species are associated with infections in immunocompromised people, especially those with AIDS. The type species is Mycobacterium tuberculosis. It is the type genus of the family Mycobacteriaceae.
[myco- + bacterium]