Mycobacterium tuberculosis, also known as Koch's bacillus, is a species of pathogenic bacteria in the family Mycobacteriaceae and the causative agent of tuberculosis. First discovered in 1882 by Robert Koch, M. tuberculosis has an unusual, waxy coating on its cell surface primarily due to the presence of mycolic acid. This coating makes the cells impervious to Gram staining, and as a result, M. tuberculosis can appear weakly Gram-positive. Acid-fast stains such as Ziehl–Neelsen, or fluorescent stains such as auramine are used instead to identify M. tuberculosis with a microscope. The physiology of M. tuberculosis is highly aerobic and requires high levels of oxygen. Primarily a pathogen of the mammalian respiratory system, it infects the lungs. The most frequently used diagnostic methods for tuberculosis are the tuberculin skin test, acid-fast stain, culture, and polymerase chain reaction.
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 and leprosy in humans. The Greek prefix myco- means 'fungus', alluding to this genus' mold-like colony surfaces. Since this genus has cell walls with a waxy lipid-rich outer layer that contains high concentrations of mycolic acid, acid-fast staining is used to emphasize their resistance to acids, compared to other cell types.
Mycobacterium avium subspecies paratuberculosis (MAP) is an obligate pathogenic bacterium in the genus Mycobacterium. It is often abbreviated M. paratuberculosis or M. avium ssp. paratuberculosis. It is the causative agent of Johne's disease, which affects ruminants such as cattle, and suspected causative agent in human Crohn's disease and rheumatoid arthritis. The type strain is ATCC 19698.
Mycobacterium smegmatis is an acid-fast bacterial species in the phylum Actinomycetota and the genus Mycobacterium. It is 3.0 to 5.0 µm long with a bacillus shape and can be stained by Ziehl–Neelsen method and the auramine-rhodamine fluorescent method. It was first reported in November 1884 by Lustgarten, who found a bacillus with the staining appearance of tubercle bacilli in syphilitic chancres. Subsequent to this, Alvarez and Tavel found organisms similar to that described by Lustgarten also in normal genital secretions (smegma). This organism was later named M. smegmatis.
A mycobacteriophage is a member of a group of bacteriophages known to have mycobacteria as host bacterial species. While originally isolated from the bacterial species Mycobacterium smegmatis and Mycobacterium tuberculosis, the causative agent of tuberculosis, more than 4,200 mycobacteriophage have since been isolated from various environmental and clinical sources. 2,042 have been completely sequenced. Mycobacteriophages have served as examples of viral lysogeny and of the divergent morphology and genetic arrangement characteristic of many phage types.
Mycobacteroides abscessus is a species of rapidly growing, multidrug-resistant, nontuberculous mycobacteria that is a common soil and water contaminant. Although M. abscessus most commonly causes chronic lung infection and skin and soft tissue infection (SSTI), it can also cause infection in almost all human organs, mostly in patients with suppressed immune systems. Amongst NTM species responsible for disease, infection caused by M. abscessus complex are more difficult to treat due to antimicrobial drug resistance.
Mycobacterium bohemicum is a species of the phylum Actinomycetota, belonging to the genus Mycobacterium.
Mycobacterium elephantis, a bacterium of the family Mycobacteriaceae, was discovered and isolated from a deceased elephant near India and may be linked to respiratory dysfunction. Organisms in the genus Mycobacterium are known to be aerobic and non-motile. Organisms within Mycobacterium belong to either the rapid growing group or the slow growing group. M. elephantis is classified as a rapid grower and relates most closely to Mycobacterium confluentis and Mycobacterium phlei.
Mycobacterium florentinum is a strain of bacteria found in humans that can cause infections and other disease conditions, and prolong sickness. It presents a high resistance to antimycobacterial drugs. It is characterized by: slow growth and a short helix 18 in the 16S rDNA.
Mycobacterium hassiacum is a rapid-growing thermophilic mycobacterium that was isolated in human urine in 1997 by researchers at the German University of Regensburg. It's a species of the phylum Actinomycetota, belonging to the genus Mycobacterium.
Mycobacteroides immunogenum is a species of bacteria from the phylum Actinomycetota, belonging to the genus Mycobacteroides.
Mycobacterium avium complex is a group of mycobacteria comprising Mycobacterium intracellulare and Mycobacterium avium that are commonly grouped because they infect humans together; this group, in turn, is part of the group of nontuberculous mycobacteria. These bacteria cause Mycobacterium avium-intracellulare infections or Mycobacterium avium complex infections in humans. These bacteria are common and are found in fresh and salt water, in household dust and in soil. MAC bacteria usually cause infection in those who are immunocompromised or those with severe lung disease.
Mycobacterium palustre is a slowly growing mycobacterium first isolated from an environmental source in Finland. It is potentially pathogenic, and has been isolated from human and veterinary clinical specimens.
Mycobacterium triplex is a species of Mycobacterium.
Mycobacterium arosiense is a newly described species of Mycobacterium. It is a scotochromogen that derives its name from Arosia, the Latin name for the city of Aarhus (Denmark), where the strain was first isolated.
Mycolicibacillus koreensis is a slow-growing, non-chromogenic species of Mycolicibacillus originally isolated from the sputum of a human patient. It grows at temperatures from 25–37 °C and is susceptible to quinolones. The genome of M. koreensis contains a tRNA array that contains a long non-coding RNA called GOLDD.
Mycobacteroides franklinii is a species of bacteria from the phylum Actinomycetota belonging to the genus Mycobacteroides. Most of the original strains were isolated from clinical specimens in Pennsylvania, but some have been found in conduit water in the Netherlands. In general, human M. franklinii infections present with symptoms similar to an infection with Mycobacteroides abscessus, but it can also be associated with tattoo infections. M. franklinii is also associated with outbreaks of mycobacteriosis in farmed fish. M. fanklinii is susceptible to cefoxitin and bedaquiline.
Mycobacteroides saopaulense is a species of bacteria from the phylum Actinomycetota belonging to the genus Mycobacteroides that was first isolated from a human patient undergoing LASIK surgery. It has also been isolated from turtles and cows. A strain isolated from mangroves has been demonstrated to produce clavulanic acid and streptomycin. The genome of M. saopaulense contains a tRNA array that contains a long non-coding RNA called GOLDD. M. saopaulense is susceptible to amikacin, kanamycin, and clarithromycin.
Mycolicibacter heraklionensis is a species of bacteria from the phylum Actinomycetota. It is susceptible to clarithromycin. It is known to cause tenosynovitis in humans, but has also been isolated from sputum, urine, and a soft-tissue ankle mass.
Mycolicibacter senuensis is a species of bacteria from the phylum Actinomycetota that was first isolated from the sputum of a patient with an unspecified pulmonary infection. It is non-pigmented and grows slowly at 25–37 °C. It has also been isolated from swine.
