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a genus of bacteria, related to actinomycetes; it differs from true bacteria in a number of ways. The young vegetative cells are rodlike (0.5–0.8 × 2.2 microns); they are capable of branching and acquiring V or Y shapes. In old cultures spherical cells predominate. Mycobacteria, which do not form endospores, are nonmotile, gram-positive, and strictly aerobic. They reproduce mainly by dividing and budding. Mycobacteria contain carotenoids, and, as a result, their colonies are often pigmented (yellow, orange, or red). Owing to their cell composition (including lipides and wax), some myco-bacteria, in contrast to other bacteria, are acid-fast.

Mycobacteria are widely distributed in soils and are active in the mineralization of plant remains. Some species of Mycobacterium are nitrogen-fixing microorganisms; others are capable of metabolizing the carbohydrates of petroleum and natural gas and, when cultured, accumulate protein, which is used for fodder and other purposes. Some species of Mycobacterium are pathogenic to humans (for example, mycobacteria are the causative agents of tuberculosis and leprosy).


References in periodicals archive ?
Neurologic manifestations of disseminated infection with Mycobacterium abscessus.
Granulation tissue obtained from both ears yielded rapidly growing Mycobacterium abscessus and Mycobacterium fortuitum that were resistant to trimethoprimsulfamethoxazole but sensitive to imipenem, clarithromycin, and azithromycin.
Our immune system uses reactive oxygen molecules in the defence against intruders, for example against Mycobacterium.
Isolation and identification of environmental mycobacteria in the Mycobacterium bovis BCG trial area of South India.
The researchers named the new species Mycobacterium lepromatosis.
Fatal pulmonary infection due to multidrug-resistent mycobacterium abscessus in a patient with cystic fibrosis.
chelonae-abscessus group, has been proposed as a new species, Mycobacterium immunogenum (Brown-Elliott and Wallace 2002).
Mycobacterium mucogenicum was formerly classified as M chelonae-like organism and is a member of the Mycobacterium fortuitum-chelonae complex.
These are the Enhanced Mycobacterium tuberculosis Direct Test (E-MTD; GenProbe, San Diego, CA) and the Amplicor Mycobacterium tuberculosis Test (Amplicor; Roche Diagnostic Systems, Inc.
When TB PNA FISH was evaluated with 30 acid-fast bacillus-positive (AFB(+) cultures from Denmark and 42 AFB(+) cultures from Thailand, 87% of the cultures were correctly identified as Mycobacterium tuberculosis complex (n = 46) or nontuberculous mycobacteria (n = 17).
Some 2 billion people -- one-third of the world's population -- are infected with the TB organism, Mycobacterium tuberculosis.

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