Mycobacterium aurum
Cultural characteristics
Biochemical characters
Phylum Actinobacteria, Class Actinobacteria, Order Actinomycetales, Suborder Corynebacterineae, Family Mycobacteriaceae, Genus
Mycobacterium aurum Tsukamura 1966.

Initially, species was thought to be a variety of
Mycobacterium parafortuitum.
Acid-fast rods,1-6 μm. No cross-baring. No cords formation. No mycelia formation.
Colonies are smooth, yellow-orange and appear in less than 5 days on inspissated
egg media. The temperature range for growth is 25-37 ºC; does not grow at 40, 45 or
52 ºC. Grows in the presence of potassium tellurite. No growth on MacConkey agar
w/o crystal violet. Variable growth on media supplemented with 5% NaCl.
Isolated from soil, and human sputum. Susceptible to hydroxylamine (250 μg/ml), ethambutol (5 μg/ml) and isoniazid (1 μg/ml).
Resistant to rifampin (25 μg/ml), and thiophene-2-carboxylic acid hydrazide (1 μg/ml). Variable results for streptomycin.
Considered to be non-pathogenic.
  1. 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.
  2. Tsukamura M. Adansonian classification of mycobacteria. J Gen Microbiol 1966; 45:253-273.
  3. Tsukamura M, Yano I, Imaeda T. Mycobacterium fortuitum subspecies acetamidolyticum, a new subspecies of Mycobacterium
    fortuitum. Microbiol Immunol 1986; 30:97-110.
  4. Schroder KH, Naumann L, Kroppenstedt RM, Reischl U. Mycobacterium hassiacum sp. nov., a new rapidly growing thermophilic
    mycobacterium. Int J Syst Bacteriol 1997; 47:86-91.
  5. 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.
    1981; 31:263-275.
  6. Tsukamura M, Van Der Meulen HJ, Grabow WOK. Numerical taxonomy of rapidly growing, scotochromogenic mycobacteria of the
    Mycobacterium parafortuitum complex: Mycobacterium austroafricanum sp. nov. and Mycobacterium diernhoferi sp. nov., nom.
    rev. Int. J. Syst. Bacteriol. 1983; 33:460-469.
  7. H. Saito, R. E. Gordon, I. Juhlin, W. Käppler, J. B. G. Kwapinski, C. McDurmont, S. R. Pattyn, E. H. Runyon, J. L. Stanford, I. Tarnok,
    H. Tasaka, M. Tsukamura And J. Weiszfeiler 1977. Cooperative Numerical Analysis of Rapidly Growing Mycobacteria. The Second
    Report. International Journal of Systematic Bacteriology, Apr.1977, p. 75-85.
  8. Stanford JL, Gunthorpe WJ. A study of some fast-growing scotochromogenic mycobacteria including species descriptions of
    Mycobacterium gilvum (new species) and Mycobacterium duvalii (new species). Br J Exp Pathol 1971; 52:627-637.
  9. Vuorio R, Andersson MA, Rainey FA, Kroppenstedt RM, Kampfer P, Busse HJ, Viljanen M, Salkinoja-Salonen M. A new rapidly
    growing mycobacterial species, Mycobacterium murale sp. nov., isolated from the indoor walls of a children's day care centre. Int
    J Syst Bacteriol 1999; 49:25-35.
  10. Nouioui I, Carro L, Sangal V, Jando M, Igual JM, Goodfellow M, Klenk HP. Formal description of Mycobacterium neglectum sp. nov.
    and Mycobacterium palauense sp. nov., rapidly growing actinobacteria. Antonie Van Leeuwenhoek 2018; 111:1209-1223.
Positive results for arylsulfatase (14 days), catalase, beta-esterase, iron uptake, pyrazinamidase, Tween 80 hydrolysis, and  urease.
Can utilize as sole carbon source glucose, fructose, sucrose, mannose, acetate, malate, fumarate, succinate, ethanol, pyruvate,
mannitol, rhamnose, xylose, and inositol.

Negative results for acid phosphatase, benzamidase, arylsulfatase (3 days), alpha-esterase (most strains), beta-galactosidase,  
isonicotinamidase, semiquantitative catalase test (most strains), and niacin accumulation (later testing of the type strain gave
positive result).
No utilization of acetamide, benzoate, citrate (most strains), malonate, galactose, and sorbitol.

Variable results for heat-stable catalase (68 ºC), nitrate reduction, acetamidase, allantoinase, nicotinamidase, utilization of trehalose.
(c) Costin Stoica
Culture media
Biochemical tests
Previous page