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Mycobactin
Mycobactin is a siderophore used by members of the genus '' Mycobacterium'' to shuttle free extracellular iron ions into the cytoplasm of mycobacterial cells. The pathogen ''M. tuberculosis'' can synthesize its own mycobactin for this purpose, however there are other mycobacteria such as '' M. avium'' subspecies ''paratuberculosis Paratuberculosis is a contagious, chronic and sometimes fatal infection that primarily affects the small intestine of ruminants. It is caused by the bacterium ''Mycobacterium avium'' subspecies ''paratuberculosis''. Infections normally affect ru ...'' that cannot produce this siderophore and thus it must be supplied to cultivate this organism in the lab. References {{Reflist Siderophores ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paratuberculosis
Paratuberculosis is a contagious, chronic and sometimes fatal infection that primarily affects the small intestine of ruminants. It is caused by the bacterium ''Mycobacterium avium'' subspecies ''paratuberculosis''. Infections normally affect ruminants (mammals that have four compartments of their stomachs, of which the rumen is one), but have also been seen in a variety of nonruminant species, including rabbits, foxes, and birds. Horses, dogs, and nonhuman primates have been infected experimentally. Paratuberculosis is found worldwide, with some states in Australia (where it is usually called bovine Johne's disease or BJD) being the only areas proven to be free of the disease. At least in Canada, the signs of BJD usually start when cattle are four to seven years of age, and then usually only are diagnosed in one animal at a time. Cattle "with signs of Johne’s disease shed billions of bacteria through their manure and serve as a major source of infection for future calves." So ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siderophore
Siderophores (Greek: "iron carrier") are small, high-affinity iron-chelating compounds that are secreted by microorganisms such as bacteria and fungi. They help the organism accumulate iron. Although a widening range of siderophore functions is now being appreciated. Siderophores are among the strongest (highest affinity) Fe3+ binding agents known. Phytosiderophores are siderophores produced by plants. Scarcity of soluble iron Despite being one of the most abundant elements in the Earth's crust, iron is not readily bioavailable. In most aerobic environments, such as the soil or sea, iron exists in the ferric (Fe3+) state, which tends to form insoluble rust-like solids. To be effective, nutrients must not only be available, they must be soluble. Microbes release siderophores to scavenge iron from these mineral phases by formation of soluble Fe3+ complexes that can be taken up by active transport mechanisms. Many siderophores are nonribosomal peptides, although several are biosynthes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 leprosy ('' M. leprae'') in humans. The Greek prefix ''myco-'' means 'fungus', alluding to this genus' mold-like colony surfaces. Since this genus has cell walls with Gram-positive and Gram-negative features, acid-fast staining is used to emphasize their resistance to acids, compared to other cell types. Metabolism and Morphology Mycobacteria are aerobic with 0.2-0.6 µm wide and 1.0-10 µm long rod shapes. They are generally non-motile, except for the species ''Mycobacterium marinum'', which has been shown to be motile within macrophages. Mycobacteria possess capsules and most do not form endospores. ''M. marinum'' and perhaps ''M. bovis'' have been shown to sporulate; however, this has been contested by further research. The disti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
