Phylum Actinobacteria, Class Actinobacteria, Order Actinomycetales, Suborder Corynebacterineae, Family Mycobacteriaceae, Genus
Mycobacterium, Mycobacterium pinnipedii Cousins et al. 2003.
Member of the Mycobacterium tuberculosis complex.
According to Riojas et al. (2018), M. pinnipedii is a later heterotypic synonym of Mycobacterium tuberculosis (Zopf 1883) Lehmann
and Neumann 1896.
Acid-alcohol-fast rods, loose cord forming. Nonspore-forming. Nonmotile.
Colonies on egg-based medium after incubation for 3-6 weeks are dysgonic, rough,
flat, and non-photochromogenic. Growth is generally enhanced by sodium pyruvate.
Optimal temperature for growth is 36-37 ºC; no growth at 22, 25, 42 or 45 ºC.
Isolated from the lung and associated lymph nodes of tuberculous pinnipeds and occasionally from mesenteric lymph nodes and
organs such as the liver. Incidental infections in bovines, humans, and a tapir suggest the species may have a wider host range.
Susceptible to thiophene-2-carboxylic acid hydrazide (TCH). New Zealand strains were resistant to 1 μg / ml, but sensitive to 10 μg /
ml. Susceptible to isoniazid, rifampicin, streptomycin, ethambutol and paraminosalicylic acid.
Pathogenic for guinea pigs and rabbits. Possible transmission to other species or humans.
- 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.
- Riojas MA, McGough KJ, Rider-Riojas CJ, Rastogi N, Hazbon MH. Phylogenomic analysis of the species of the Mycobacterium
tuberculosis omplex demonstrates that Mycobacterium africanum, Mycobacterium bovis, Mycobacterium caprae, Mycobacterium
microti and Mycobacterium pinnipedii are later heterotypic synonyms of Mycobacterium tuberculosis. Int J Syst Evol Microbiol
- Cousins DV, Bastida R, Cataldi A, Quse V, Redrobe S, Dow S, Duignan P, Murray A, Dupont C, Ahmed N, et al. Tuberculosis in
seals caused by a novel member of the Mycobacterium tuberculosis complex: Mycobacterium pinnipedii sp. nov. Int J Syst Evol
Microbiol 2003; 53:1305-1314.
Biochemically similar to Mycobacterium bovis.
Positive result for pyrazinamidase.
Negative results for nitrate reduction and niacin production (some strains, including the isolates from New Zealand, gave weak or
positive reactions in the niacin accumulation test).
(c) Costin Stoica