Mycobacterium cookii

Mycobacterium cocci
Scientific classification
Kingdom:	Bacteria
Phylum:	Actinobacteria
Order:	Actinomycetales
Suborder:	Corynebacterineae
Family:	Mycobacteriaceae
Genus:	Mycobacterium
Species:	M. cookii
Binomial name
Mycobacterium cookii Kazda et al. 1990, ATCC 51304

Mycobacterium cookii is a species of the phylum actinobacteria (Gram-positive bacteria with high guanine and cytosine content, one of the dominant phyla of all bacteria), belonging to the genus mycobacterium.

Description

Gram-positive, nonmotile and polymorphic acid-fast rods (0.8 µm x 1.4–1.9 µm). Forms clumps, but not cords or cross bands. Does not form spores, capsules and aerial hyphae.

Colony characteristics

• Colonies are smooth and glistening with yellow-orange pigmentation (0.5–1.0 mm diameter, scotochromogenic).

Physiology

• Slow growth on Löwenstein-Jensen medium or Middlebrook 7H10 agar at 31°C (optimal temperature). No growth at 37°C, 42°C or 45°C.
• Most of the strains are susceptible to ethambutol, isoniazid, streptomycin, and rifampin.

Differential characteristics

• Phylogenetic position between the slowly growing pathogenic species and the saprotrophic rapidly growing species by partial 16S rDNA sequencing.

Pathogenesis

• Not pathogenic for humans, mice, guinea pigs and rabbits. Biosafety level 1.
• Provokes a non-specific hypersensitivity reaction to bovine tuberculin.

Type strain

Strain NZ2 = ATCC 49103 = CIP 105396 = DSM 43922 = JCM 12404.

References

• Kazda et al. 1990. Mycobacterium cookii sp. nov. Int. J. Syst. Bacteriol.,40, 217-223.