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Scotochromogen
Scotochromogenic bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ... develop pigment in the dark. Runyon Group II nontuberculous mycobacteria such as Mycobacterium gordonae are examples but the term could apply to many other organisms. References Bacteria {{Bacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Runyon Classification
The Timpe and Runyon classification of nontuberculous mycobacteria based on the rate of growth, production of yellow pigment and whether this pigment was produced in the dark or only after exposure to light. It was introduced by Ernest Runyon in 1959. On these bases, the nontuberculous mycobacteria are divided into four groups: Slowly growing Mycobacteria The first three groups are classified as "Slowly growing Mycobacteria". Runyon I: Photochromogens Runyon I organisms ( photochromogens) are slow growing, and produce a yellow-orange pigment when exposed to light. The group includes ''Mycobacterium kansasii'', '' Mycobacterium marinum'', '' Mycobacterium asiaticum'', and ''Mycobacterium simiae''. ''Mycobacterium szulgai'' is a photochromogen when grown at 24 degrees, and a scotochromogen at 37 degrees. In contrast, Runyon classifications III through IV are considered ''nonphotochromogens'', in that exposure to light does not make them produce pigment which they would not d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycobacterium Gordonae
''Mycobacterium gordonae'' is a species of '' Mycobacterium'' named for Ruth E. Gordon. It is a species of the phylum Actinomycetota (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 moderate to long acid-fast rods. *Commonly found in tap water and soil. Casual resident in human sputum and gastric lavage specimens. Colony characteristics *Smooth, with yellow or orange scotochromogenic colonies. Even though they are scotochromogenic pigment is intensified by growing in continuous light. Physiology *Growth on Löwenstein-Jensen medium and Middlebrook 7H10 agar within 7 or more days at 37 °C (optimal 25 °C). *Does not grow in the presence of ethambutol (1 mg/L), isoniazid (10 mg/L) and sodium chloride (5%). *Some strains can grow using carbon monoxide as a carbon and energy source. Differential characteristics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycobacteria
''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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, Hot spring, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the nitrogen fixation, fixation of nitrogen from the Earth's atmosphere, atmosphere. The nutrient cycle includes the decomposition of cadaver, dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
