''Mycobacterium cookii'' is a species of the phylum

Actinomycetota The ''Actinomycetota'' (or ''Actinobacteria'') are a phylum of all gram-positive bacteria. They can be terrestrial or aquatic. They are of great economic importance to humans because agriculture and forests depend on their contributions to soi ...

(

Gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bac ...

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...

with high guanine and cytosine content, one of the dominant phyla of all bacteria), belonging to the genus ''

Mycobacterium ''Mycobacterium'' is a genus of over 190 species in the phylum Actinomycetota, assigned its own family, Mycobacteriaceae. This genus includes pathogens known to cause serious diseases in mammals, including tuberculosis (''M. tuberculosis'') and l ...

''.

Description

, nonmotile and polymorphic acid-fast rods (0.8

µm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Uni ...

x 1.4–1.9 µm). Forms clumps, but not cords or cross bands. Does not form

spores In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, ...

, capsules and aerial

hyphae A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or ...

. Colony characteristics *

Colonies In modern parlance, a colony is a territory subject to a form of foreign rule. Though dominated by the foreign colonizers, colonies remain separate from the administration of the original country of the colonizers, the '' metropolitan state' ...

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 Ethambutol (EMB, E) is a medication primarily used to treat tuberculosis. It is usually given in combination with other tuberculosis medications, such as isoniazid, rifampicin and pyrazinamide. It may also be used to treat ''Mycobacterium av ...

isoniazid Isoniazid, also known as isonicotinic acid hydrazide (INH), is an antibiotic used for the treatment of tuberculosis. For active tuberculosis it is often used together with rifampicin, pyrazinamide, and either streptomycin or ethambutol. For ...

streptomycin Streptomycin is an antibiotic medication used to treat a number of bacterial infections, including tuberculosis, ''Mycobacterium avium'' complex, endocarditis, brucellosis, ''Burkholderia'' infection, plague, tularemia, and rat bite fever ...

, and

rifampin Rifampicin, also known as rifampin, is an ansamycin antibiotic used to treat several types of bacterial infections, including tuberculosis (TB), ''Mycobacterium avium'' complex, leprosy, and Legionnaires’ disease. It is almost always used ...

. Differential characteristics *Phylogenetic position between the slowly growing

pathogenic In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a ger ...

species and the

saprotrophic Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs, and is most often associated with fungi ( ...

rapidly growing species by partial

16S rDNA 16 S ribosomal RNA (or 16 S rRNA) is the RNA component of the 30S subunit of a prokaryotic ribosome (SSU rRNA). It binds to the Shine-Dalgarno sequence and provides most of the SSU structure. The genes coding for it are referred to as 16S rRN ...

sequencing.

Pathogenesis

*Not pathogenic for

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

mice A mouse ( : mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...

guinea pig The guinea pig or domestic guinea pig (''Cavia porcellus''), also known as the cavy or domestic cavy (), is a species of rodent belonging to the genus '' Cavia'' in the family Caviidae. Breeders tend to use the word ''cavy'' to describe the ...

s and

rabbit Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also contains the hares) of the order Lagomorpha (which also contains the pikas). ''Oryctolagus cuniculus'' includes the European rabbit s ...

s. Biosafety level 1. *Provokes a non-specific hypersensitivity reaction to bovine

tuberculin Tuberculin, also known as purified protein derivative, is a combination of proteins that are used in the diagnosis of tuberculosis. This use is referred to as the tuberculin skin test and is recommended only for those at high risk. Reliable admin ...

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.

External links

Type strain of ''Mycobacterium cookii'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
Acid-fast bacilli cookii Bacteria described in 1990 {{Mycobacterium-stub