Phylum Actinobacteria, Class Actinobacteria, Order Actinomycetales, Suborder Corynebacterineae, Family Mycobacteriaceae, Genus
Mycobacterium, Mycobacterium hassiacum Schroder et al. 1997.
Species description is based on a single isolate.
Partially acid-fast rods which are longer and thinner following growth at higher
Colonies are 2-5 mm in diameter, smooth, and scotochromogenic after 2-3 days
incubation on Lowenstein-Jensen medium. In dense growth, colonies are slimy, but
when grown at 40-65 ºC, they are distinct and drier. The temperature range for growth
is 30-65 ºC; higher temperatures seem to favor growth. Growth occurs on MacConkey
agar (without crystal violet) and on media supplemented with 5% (w/v) NaCl.
Isolated from urine. Susceptible to streptomycin, ethambutol, cycloserine, ciprofloxacin, and clarithromycin. Resistant to isoniazid,
rifampin, and prothionamide.
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.
- 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.
Positive results for acid phosphatase (weak reaction), semiquantitative catalase test, heat-stable catalase (68 ºC), pyrazinamidase,
benzamidase, nicotinamidase, succinamidase, and urease.
Negative results for arylsulfatase, acetamidase, allantoinamidase, iron uptake, niacin, nitrate reduction, succinamidase, and Tween
No utilization as sole carbon source of citrate (positive in Bergey's Manual - admin note) and sugars.
(c) Costin Stoica