''Mycobacterium heidelbergense'' is a

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 bacte ...

, nonmotile,

acid-fast Acid-fastness is a physical property of certain bacterial and eukaryotic cells, as well as some sub-cellular structures, specifically their resistance to decolorization by acids during laboratory staining procedures. Once stained as part of a sam ...

coccobacillus A coccobacillus (plural coccobacilli), or bacilluscocco, is a type of bacterium with a shape intermediate between cocci (spherical bacteria) and bacilli (rod-shaped bacteria). Coccobacilli, then, are very short rods which may be mistaken for cocci ...

. It 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 ...

(

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 among ...

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 ...

''.

Description

Dimensions: 0.5-0.8 µm x 2.0-3.0 µm Colony characteristics: Smooth, dome-like and nonpigmented

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'' ...

Löwenstein–Jensen medium Löwenstein–Jensen medium, more commonly known as LJ medium, is a growth medium specially used for culture of '' Mycobacterium'' species, notably '' Mycobacterium tuberculosis''. When grown on LJ medium, ''M. tuberculosis'' appears as brown, ...

at 35 °C (0.5–1 mm in diameter).

Physiology Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemical ...

: Slow growth on Löwenstein–Jensen medium at 35 °C within 3–4 weeks, optimal growth at a range from 33 to 35 °C, but also growth at 30 and 37 °C, growth at neither 25 nor at 45 °C, susceptible to

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 l ...

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

and

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 avium ...

, resistant to

pyrazinamide Pyrazinamide is a medication used to treat tuberculosis. For active tuberculosis, it is often used with rifampicin, isoniazid, and either streptomycin or ethambutol. It is not generally recommended for the treatment of latent tuberculosis. It i ...

and

cycloserine Cycloserine, sold under the brand name Seromycin, is a GABA transaminase inhibitor and an antibiotic, used to treat tuberculosis. Specifically it is used, along with other antituberculosis medications, for active drug resistant tuberculosis. It ...

Differential characteristics: Differentiation from ''M. malmoense'', (bearing a strong phenotypic resemblance to ''M. heidelbergense''), by its wider range of susceptibility to antituberculous drugs, (including isoniazid), and by its inability to grow on Löwenstein–Jensen medium at 25 °C, differentiation of ''M. triplex'' from ''M. heidelbergense'' by its positive nitrate reduction test and by its characteristic

HPLC High-performance liquid chromatography (HPLC), formerly referred to as high-pressure liquid chromatography, is a technique in analytical chemistry used to separate, identify, and quantify each component in a mixture. It relies on pumps to pa ...

profile (triple-mycolate pattern). Pathogenesis occurs in

cervical lymph nodes Cervical lymph nodes are lymph nodes found in the neck. Of the 800 lymph nodes in the human body, 300 are in the neck. Cervical lymph nodes are subject to a number of different pathological conditions including tumours, infection and inflammati ...

(

lymphadenitis Lymphadenopathy or adenopathy is a disease of the lymph nodes, in which they are abnormal in size or consistency. Lymphadenopathy of an inflammatory type (the most common type) is lymphadenitis, producing swollen or enlarged lymph nodes. In cli ...

) in immunocompetent patients. Its biosafety level is not known. The type strain was first isolated from an immunocompetent paediatric patient with cervical lymphadenitis with recurrent

fistula A fistula (plural: fistulas or fistulae ; from Latin ''fistula'', "tube, pipe") in anatomy is an abnormal connection between two hollow spaces (technically, two epithelialized surfaces), such as blood vessels, intestines, or other hollow or ...

formation, in

Heidelberg Heidelberg (; Palatine German language, Palatine German: ''Heidlberg'') is a city in the States of Germany, German state of Baden-Württemberg, situated on the river Neckar in south-west Germany. As of the 2016 census, its population was 159,914 ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

.Haas ''et al.'' 1997. A new agent of mycobacterial lymphadenitis in children: Mycobacterium heidelbergense sp. nov. J. Clin. Microbiol. 35, 3203-3209. It is strain 2554/91 = ATCC 51253 = CIP 105424 = DSM 44471.

References

External links

Type strain of ''Mycobacterium heidelbergense'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
{{DEFAULTSORT:Mycobacterium Heidelbergense Acid-fast bacilli heidelbergense Bacteria described in 1998