Phylum Actinobacteria, Class Actinobacteria, Order Actinomycetales, Suborder Corynebacterineae, Family Mycobacteriaceae, Genus
Mycobacterium, Mycobacterium smegmatis (Trevisan 1889) Lehmann and Neumann 1899.
Possible old synonym: "Smegma Bacillus" Alvarez and Tavel (1885).
Members of the Mycobacterium smegmatis group 2 and 3 were moved to Mycobacterium goodii and Mycobacterium wolinskyi species,
Acid-fast rods, 3-5 μm long, occasionally curved with branching or Y-shaped cells.
Cells are sometimes swollen and may appear as deeper staining beaded or ovoid
forms. In cultures older than 5-7 days non-acid-fast forms begin to develop. No cord
Colonies that appear on Löwenstein–Jensen medium in 2-4 days are usually rough,
wrinkled or coarsely folded, and nonpigmented or creamy white. Smooth, glistening,
butyrous colonies are seen, but pigmentation is rare, though it may be seen in older
cultures. On Middlebrook agar, the rough colonial form appears smooth textured over
a rugose, but non-corded, granular colony; the smooth form is domed, smooth
textured, and granular. Feshly isolated strains may show smooth colonies, whereas
strains maintained in the laboratory may show rough colonies. Temperature range
for growth is 25-45 ºC. Can grow on media supplemented with 5% (w/v) NaCl. No
growth on MacConkey agar.
Isolated from smegma. Resistant to tiophene-2-carboxylic acid hydrazide (1 µg/ml) and rifampicin (25 µg/ml).
Susceptible to hydroxylamine (500 µg/ml).
It i usually associated with secretions of the normal genitalia and with soft lesions following accidental or surgical trauma.
Not pathogenic for chickens, guinea pigs, hamsters, or mice, but pathogenic cultures may be obtained from the spleens of guinea
pigs and/or mice.
- John G. Magee and Alan C. Ward 2012. Family III. Mycobacteriaceae Chester 1897, 63AL in Bergey’s Manual of Systematic
Bacteriology, Volume Five The Actinobacteria, Part A, Michael Goodfellow & al. (editors), 312-375.
- Loredana Gabriela Popa, Mircea Ioan Popa 2009. Identificarea bacililor acido-rezistenti in: Tratat de microbiologie clinica, Dumitru
Buiuc, Marian Negut, ed. a III-a, Editura Medicala, 881-890, ISBN (13) 978-973-39-0593-6.
- Bojalil LF, Cerbon J, Trujillo A. Adansonian classification of mycobacteria. J Gen Microbiol 1962; 28:333-346.
- Kubica GP, Baess I, Gordon RE, Jenkins PA, Kwapinski JB, McDurmont C, Pattyn SR, Saito H, Silcox V, Stanford JL, et al. A co-
operative numerical analysis of rapidly growing mycobacteria. J Gen Microbiol 1972; 73:55-70.
- Tsukamura M, Yano I, Imaeda T. Mycobacterium fortuitum subspecies acetamidolyticum, a new subspecies of Mycobacterium
fortuitum. Microbiol Immunol 1986; 30:97-110.
- Tsukamura M. A Review of the Methods of Identification and Differentiation of Mycobacteria. Reviews of Infectious Diseases, Vol. 3,
No. 5, International Conference on Atypical Mycobacteria (Sep. - Oct., 1981), pp. 841-861.
- J L Stanford, A Beck. Bacteriological and Serological Studies of Fast Growing Mycobacteria Identified as Mycobacterium
Friedmannii. J Gen Microbiol, 58 (1), 99-106 Sep 1969.
- Stephen Berger 2019. GIDEON Guide to Medically Important Bacteria, eBook.
- Brown BA, Springer B, Steingrube VA, Wilson RW, Pfyffer GE, Garcia MJ, Menendez MC, Rodriguez-Salgado B, Jost KCJ, Chiu SH,
et al. Mycobacterium wolinskyi sp. nov. and Mycobacterium goodii sp. nov., two new rapidly growing species related to
Mycobacterium smegmatis and associated with human wound infections: a cooperative study from the International Working
Group on Mycobacterial Taxonomy. Int J Syst Bacteriol 1999; 49:1493-1511.
Positive results for semiquantitative catalase test, beta-galactosidase, iron uptake, nitrate reduction, nicotinamidase, pyrazinamidase,
tellurite reduction, Tween hydrolysis and urea hydrolysis.
Can utilize benzoate, citrate, mannitol, glucose, acetate, pyruvate, succinate, malate, fumarate, malonate, mucate, propanol, butanol,
propionate, arabinose, xylose, rhamnose, trehalose, inositol, sorbitol as sole carbon source.
Negative results for arylsulfatase (3 days), acid phosphatase, alpha-esterase (most strains), thermostable catalase (68 ºC), and
(c) Costin Stoica