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Spiral Bacteria
Spiral bacteria, bacteria of spiral (helical) shape, form the third major morphological category of prokaryotes along with the rod-shaped bacilli and round cocci. Spiral bacteria can be subclassified by the number of twists per cell, cell thickness, cell flexibility, and motility. The two types of spiral cells are spirillum and spirochete, with spirillum being rigid with external flagella, and spirochetes being with internal flagella. Spirillum A spirillum (plural spirilla) is a rigid spiral bacterium that is Gram-negative and frequently has external amphitrichous or lophotrichous flagella. Examples include: * Members of the genus ''Spirillum'' * '' Campylobacter'' species, such as ''Campylobacter jejuni'', a foodborne pathogen that causes campylobacteriosis * ''Helicobacter'' species, such as ''Helicobacter pylori'', a cause of peptic ulcers Spirochetes A spirochete (plural spirochetes) is a very thin, elongate, flexible, spiral bacteria that is motile via internal peripla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, 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 fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of 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 sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campylobacteriosis
Campylobacteriosis is an infection by the '' Campylobacter'' bacterium, most commonly ''C. jejuni''. It is among the most common bacterial infections of humans, often a foodborne illness. It produces an inflammatory, sometimes bloody, diarrhea or dysentery syndrome, mostly including cramps, fever and pain. Symptoms and signs The prodromal symptoms are fever, headache, and myalgia, which can be severe, lasting as long as 24 hours. After 1–5 days, typically, these are followed by diarrhea (as many as 10 watery, frequently bloody, bowel movements per day) or dysentery, cramps, abdominal pain, and fever as high as 40 °C (104 °F). In most people, the illness lasts for 2–10 days. It is classified as invasive/inflammatory diarrhea, also described as bloody diarrhea or dysentery. There are other diseases showing similar symptoms. For instance, abdominal pain and tenderness may be very localized, mimicking acute appendicitis. Furthermore, ''Helicobacter pylori'' is closely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borrelia Burgdorferi
''Borrelia burgdorferi'' is a bacterial species of the spirochete class in the genus ''Borrelia'', and is one of the causative agents of Lyme disease in humans. Along with a few similar genospecies, some of which also cause Lyme disease, it makes up the species complex of ''Borrelia burgdorferi'' sensu lato. The complex currently comprises 20 accepted and 3 proposed genospecies. ''B. burgdorferi'' sensu stricto exists in North America and Eurasia and until 2016 was the only known cause of Lyme disease in North America. ''Borrelia'' species are Gram-negative. Microbiology ''Borrelia burgdorferi'' is named after the researcher Willy Burgdorfer, who first isolated the bacterium in 1982. ''Borrelia burgdorferi'' is a microaerophile, requiring small amounts of oxygen in order to undergo glycolysis and survive. Like all other ''Borrelia'' sps., this bacterium is also gram-negative and a spirochete. Borrelia colonies are often smaller, rounded, and white with an elevated center. ''B. b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borrelia
''Borrelia'' is a genus of bacteria of the spirochete phylum. Several species cause Lyme disease, also called Lyme borreliosis, a zoonotic, vector-borne disease transmitted by ticks. Other species of ''Borrelia'' cause relapsing fever, and are transmitted by ticks or lice, depending on the species of bacteria. A few ''Borrelia'' species as ''Candidatus'' Borrelia mahuryensis harbor intermediate genetic features between Lyme disease and relapsing fever ''Borrelia''. The genus is named after French biologist Amédée Borrel (1867–1936), who first documented the distinction between a species of ''Borrelia'', ''B. anserina'', and the other known type of spirochete at the time, ''Treponema pallidum''. This bacterium must be viewed using dark-field microscopy, which make the cells appear white against a dark background. ''Borrelia'' species are grown in Barbour-Stoenner-Kelly medium. Of 52 known species of ''Borrelia'', 20 are members of the Lyme disease group (with an additional 3 p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leptospirosis
Leptospirosis is a blood infection caused by the bacteria ''Leptospira''. Signs and symptoms can range from none to mild (headaches, muscle pains, and fevers) to severe ( bleeding in the lungs or meningitis). Weil's disease, the acute, severe form of leptospirosis, causes the infected individual to become jaundiced (skin and eyes become yellow), develop kidney failure, and bleed. Bleeding from the lungs associated with leptospirosis is known as severe pulmonary haemorrhage syndrome. More than ten genetic types of ''Leptospira'' cause disease in humans. Both wild and domestic animals can spread the disease, most commonly rodents. The bacteria are spread to humans through animal urine, or water and soil contaminated with animal urine, coming into contact with the eyes, mouth, nose or breaks in the skin. In developing countries, the disease occurs most commonly in farmers and low-income people who live in areas with poor sanitation. In developed countries, it occurs during heavy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leptospira
''Leptospira'' ( grc, leptos, italics=yes, 'fine, thin' and la, spira, links=no, 'coil') is a genus of spirochaete bacteria, including a small number of pathogenic and saprophytic species. ''Leptospira'' was first observed in 1907 in kidney tissue slices of a leptospirosis victim who was described as having died of "yellow fever". Taxonomy ''Leptospira'', together with the genera ''Leptonema'' and ''Turneria'', is a member of the family Leptospiraceae. The genus ''Leptospira'' is divided into 20 species based on DNA hybridization studies. Pathogenic ''Leptospira'' :''Leptospira alstonii'' Smythe et al. 2013 ''Leptospira alstoni''" Haake et al. 1993:''Leptospira interrogans'' (Stimson 1907) Wenyon 1926 emend. Faine and Stallman 1982 ["''Spirochaeta interrogans''" Stimson 1907; "''Spirochaeta nodosa''" Hubener & Reiter 1916; "''Spirochaeta icterohaemorrhagiae''" Inada et al. 1916; "''Spirochaeta icterogenes''" Uhlenhuth & Fromme 1916; "''Leptospira icteroides''" Noguchi 1919 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warthin–Starry Stain
The Warthin–Starry stain (WS) is a silver nitrate-based staining method (a silver stain) used in histology. It was first introduced in 1920 by American pathologists Aldred Scott Warthin (1866-1931) and Allen Chronister Starry (1890-1973), for the detection of spirochetes. It has been considered a standard stain for the detection of spirochetes, and is also used to stain ''Helicobacter pylori'', ''Lawsonia intracellularis'', ''Microsporidia'', and particulates. It is also important for confirmation of ''Bartonella henselae'', a causative organism in cat-scratch disease Cat-scratch disease (CSD) or felinosis is an infectious disease that most often results from a scratch or bite of a cat. Symptoms typically include a non-painful bump or blister at the site of injury and painful and swollen lymph nodes. People m .... Warthin–Starry stains organisms dark brown to black, and the background light golden brown/golden yellow. See also * Dieterle stain References External links ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dark Field Microscopy
Dark-field microscopy (also called dark-ground microscopy) describes microscopy methods, in both light and electron microscopy, which exclude the unscattered beam from the image. As a result, the field around the specimen (i.e., where there is no specimen to scatter the beam) is generally dark. In optical microscopes a darkfield condenser lens must be used, which directs a cone of light away from the objective lens. To maximize the scattered light-gathering power of the objective lens, oil immersion is used and the numerical aperture (NA) of the objective lens must be less than 1.0. Objective lenses with a higher NA can be used but only if they have an adjustable diaphragm, which reduces the NA. Often these objective lenses have a NA that is variable from 0.7 to 1.25. Light microscopy applications In optical microscopy, dark-field describes an illumination technique used to enhance the contrast in unstained samples. It works by illuminating the sample with light that wil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirochaete
A spirochaete () or spirochete is a member of the phylum Spirochaetota (), (synonym Spirochaetes) which contains distinctive diderm (double-membrane) gram-negative bacteria, most of which have long, helically coiled (corkscrew-shaped or spiraled, hence the name) cells. Spirochaetes are chemoheterotrophic in nature, with lengths between 3 and 500 μm and diameters around 0.09 to at least 3 μm. Spirochaetes are distinguished from other bacterial phyla by the location of their flagella, called endoflagella which are sometimes called ''axial filaments''. Endoflagella are anchored at each end (pole) of the bacterium within the periplasmic space (between the inner and outer membranes) where they project backwards to extend the length of the cell. These cause a twisting motion which allows the spirochaete to move about. When reproducing, a spirochaete will undergo asexual transverse binary fission. Most spirochaetes are free-living and anaerobic, but there are numero ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagellum
A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have from one to many flagella. A gram-negative bacterium ''Helicobacter pylori'' for example uses its multiple flagella to propel itself through the mucus lining to reach the stomach epithelium, where it may cause a gastric ulcer to develop. In some bacteria the flagellum can also function as a sensory organelle, being sensitive to wetness outside the cell. Across the three domains of Bacteria, Archaea, and Eukaryota the flagellum has a different structure, protein composition, and mechanism of propulsion but shares the same function of providing motility. The Latin word means " whip" to describe its lash-like swimming motion. The flagellum in archaea is called the archaellum to note its difference from the bacterial flagellum. Eukaryotic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirochaete
A spirochaete () or spirochete is a member of the phylum Spirochaetota (), (synonym Spirochaetes) which contains distinctive diderm (double-membrane) gram-negative bacteria, most of which have long, helically coiled (corkscrew-shaped or spiraled, hence the name) cells. Spirochaetes are chemoheterotrophic in nature, with lengths between 3 and 500 μm and diameters around 0.09 to at least 3 μm. Spirochaetes are distinguished from other bacterial phyla by the location of their flagella, called endoflagella which are sometimes called ''axial filaments''. Endoflagella are anchored at each end (pole) of the bacterium within the periplasmic space (between the inner and outer membranes) where they project backwards to extend the length of the cell. These cause a twisting motion which allows the spirochaete to move about. When reproducing, a spirochaete will undergo asexual transverse binary fission. Most spirochaetes are free-living and anaerobic, but there are numero ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Treponema Pallidum
''Treponema pallidum'', formerly known as ''Spirochaeta pallida'', is a spirochaete bacterium with various subspecies that cause the diseases syphilis, bejel (also known as endemic syphilis), and yaws. It is transmitted only among humans. It is a helically coiled microorganism usually 6–15 μm long and 0.1–0.2 μm wide. ''T. pallidum'''s lack of either a tricarboxylic acid cycle or oxidative phosphorylation results in minimal metabolic activity. The treponemes have a cytoplasmic and an outer membrane. Using light microscopy, treponemes are visible only by using dark field illumination. ''Treponema pallidum'' consists of three subspecies, ''T. p. pallidum, T. p. endemicum,'' and ''T. p. pertenue,'' each of which has a distinct associated disease. Subspecies Three subspecies of ''T. pallidum'' are known: * ''Treponema pallidum pallidum'', which causes syphilis * ''T. p. endemicum'', which causes bejel or endemic syphilis * ''T. p. pertenue'', which causes yaws The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
