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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 ?
Prevalence of serum antibodies to Mycobacterium avium subsp.
Herd-level prevalence of Mycobacterium avium subsp.
Modulation of cytokine gene expression and secretion during the periparturient period in dairy cows naturally infected with Mycobacterium avium subsp.
Development of a firefly luciferase-based assay for determining antimicrobial susceptibility of Mycobacterium avium subsp.
Sequential development of histologic lesions and their relationship with bacterial isolation, faecal shedding, and immune responses during progressive stages of experimental infection of lambs with Mycobacterium avium subsp.
Johne's disease caused by Mycobacterium avium subsp.
Effects of Gamma Interferon, Interleukin-10, and Transforming Growth Factor p on the Survival of Mycobacterium avium subsp.

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