Phylum Actinobacteria, Class Actinobacteria, Order Actinomycetales, Suborder Corynebacterineae, Family Mycobacteriaceae, Genus
Mycobacterium, Mycobacterium salmoniphilum (ex Ross 1960) Whipps et al. 2007.
Old synonyms: ‘M. salmoniphilum’ Ross 1960, 'M. chelonae subsp. piscarium’ Arakawa and Fryer, 1984.
Acid-fast bacilli, slender or slightly curved, 0.25-0.6 x 1-4 μm.
Colonies on Middlebrook 7H10 agar, blood agar, and Lowenstein–Jensen slants,
are cream-coloured, smooth, shiny, and become visible after 4-6 days. After 10 days
incubation colonies tend to appear waxy, with an irregular border and ‘fried egg’
morphology. Growth is observed at 20, 28 and 30 ºC. Weak or delayed growth may
occur at 10 ºC, and no growth is observed at 37, 42 or 45 ºC. Grows on MacConkey
agar. No growth in 5% NaCl media (some strains were not tested). Grows on
potassium tellurite agar.
Mortality was recorded in experimentally infected salmon; however the infection remained subclinical in the majority of infected fish
over the 131 days challenge period.
Isolated from Atlantic salmon (Salmon salar L), Chinook salmon (Oncorhynchus tshawytscha), and Steelhead trout (Oncorhynchus
mykiss). Resistant to hydroxylamine, 250 μg/ml (most strains) and ethambutol 5 μg/ml.
- Whipps CM, Butler WR, Pourahmad F, Watral VG, Kent ML. Molecular systematics support the revival of Mycobacterium
salmoniphilum (ex Ross 1960) sp. nov., nom. rev., a species closely related to Mycobacterium chelonae. Int J Syst Evol Microbiol
- Arakawa, C. K. & Fryer, J. L. (1984). Isolation and characterization of a new subspecies of Mycobacterium chelonei infectious for
salmonid fish. Helgolander Meeresunters 37, 329–342.
- Q. Ashton Acton (ed.). Advances in Salmo Research and Application: 2012 Edition, Scholarly Brief, Chapter 1 Salmo salar 1-38.
- 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.
Positive results for acid phosphatase, arylsulfatase (3 and 14 days), catalase, urease, acid production from glucose and mannose.
Can utilize e as a sole carbon source of glucose, citrate (most strains), fumarate (most strains), succinate (most strains).
Negative results for acetamidase, benzamidase, isonicotinamidase, nicotinamidase, pyrazinamidase, allantoinase, succinamidase,
thermostable catalase (68 ºC), hippurate hydrolysis, iron uptake, niacin production, nitrate reduction, Tween hydrolysis. No acid
production from arabinose, fructose, galactose, inositol, mannitol, mannose, rhamnose, sorbitol, sucrose, trehalose, and xylose.
No utilization as sole carbon source of benzoate.
(c) Costin Stoica