Phylum Actinobacteria, Class Actinobacteria, Order Actinomycetales, Suborder Corynebacterineae, Family Mycobacteriaceae, Genus
Mycobacterium, Mycobacterium obuense (ex Tsukamura and Mizuno 1971) Tsukamura and Mizuno 1981.
Acid-fast rods, 2-6 μm. Prolonged culture may lose some acid-fastness. Mycelium not
formed. Rough mutants form spreading pellicles that contain microscopic cords.
Dilute inocula on inspissated egg media yield smooth yellow-orange colonies
in 5 days or less. Grows at 25-37 ºC, but not at 45 or 52 ºC. No growth in 4% NaCl.
Isolated from soil and from the sputum of one patient, in Obu, Japan. Susceptible to hydroxylamine (500 μg/ml). Resistant to
thiophene-2-carboxylic acid hydrazide (1 μg/ml), ethambutol (5 μg/ml), and rifampin (25 μg/ml).
Considered to be non-pathogenic.
- 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.
- Julian E, Roldan M, Sanchez-Chardi A, Astola O, Agusti G, Luquin M. Microscopic cords, a virulence-related characteristic of
Mycobacterium tuberculosis, are also present in nonpathogenic mycobacteria. J Bacteriol. 2010;192(7):1751–1760. doi:10.1128
- Tsukamura M, Mizuno S, Tsukamura S. Numerical analysis of rapidly growing, scotochromogenic mycobacteria, including
Mycobacterium obuense sp. nov., nom. rev., Mycobacterium rhodesiae sp. nov., nom. rev., Mycobacterium aichiense sp. nov.,
nom. rev., Mycobacterium chubuense sp. nov., nom. rev., and Mycobacterium tokaiense sp. nov., nom. rev. Int. J. Syst. Bacteriol.
- Nouioui I, Brunet LR, Simpson D, Klenk HP, Goodfellow M. Description of a novel species of fast growing mycobacterium:
Mycobacterium kyogaense sp. nov., a scotochromogenic strain received as Mycobacterium vaccae. Int J Syst Evol Microbiol 2018;
Positive results for arylsulfatase (3 and 7 days), alpha- and beta-esterase,
beta-galactosidase, nicotinamidase, pyrazinamidase, tellurite reduction, and urease.
Can utilize as sole carbon source fructose, glucose, sucrose, trehalose, ethanol, succinate, malate, fumarate, acetate, pyruvate .
Negative results for acid phosphatase, acetamidase, benzamidase, catalase, semiquantitative catalase test, thermo-stable catalase,
niacin accumulation, nitrate reduction, and Tween 80 hydrolysis (positive after 14 days).
No utilization of benzoate, citrate, malonate, acetamide, myo-inositol, and xylose.
(c) Costin Stoica