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Legionella Anisa
''Legionella anisa'' is a Gram-negative bacterium, one of more than 40 species in the family Legionellaceae. After ''Legionella pneumophila'', this species has been isolated most frequently from water samples. This species is also one of the several pathogenic forms of ''Legionella'' having been associated with rare clinical cases of illness including Pontiac fever and Legionnaires' disease. History This species was first isolated from water during a nosocomial outbreak in the United States between March 1980 and June 1981. The type strain of ''L. anisa'' is WA-316-C3 (ATCC 35292). The first reported clinical detection was in 1986, with a female patient in Victoria, Australia, who presented with pneumonia. Similar to other '' Legionella'' species, person-to-person transmission has not been documented. Structure Like other ''Legionella'' species, ''L. anisa'' is a thin, aerobic, pleomorphic, flagellated, non-spore-forming, Gram-negative bacterium. A distinguishing character ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-negative
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall sandwiched between an inner cytoplasmic cell membrane and a bacterial outer membrane. Gram-negative bacteria are found in virtually all environments on Earth that support life. The gram-negative bacteria include the model organism ''Escherichia coli'', as well as many pathogenic bacteria, such as ''Pseudomonas aeruginosa'', '' Chlamydia trachomatis'', and '' Yersinia pestis''. They are a significant medical challenge as their outer membrane protects them from many antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and lysozyme, an antimicrobial enzyme produced by animals that forms part of the innate immune system. Additionally, the outer leaflet of this membrane comprises a comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacterium
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 rela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Legionellaceae
''Legionella'' is a genus of pathogenic gram-negative bacteria that includes the species '' L. pneumophila'', causing legionellosis (all illnesses caused by ''Legionella'') including a pneumonia-type illness called Legionnaires' disease and a mild flu-like illness called Pontiac fever. ''Legionella'' may be visualized with a silver stain or cultured in cysteine-containing media such as buffered charcoal yeast extract agar. It is common in many environments, including soil and aquatic systems, with at least 50 species and 70 serogroups identified. These bacteria, however, are not transmissible from person to person; furthermore, most people exposed to the bacteria do not become ill. Most outbreaks are traced to poorly maintained cooling towers. The side chains of the cell wall carry the bases responsible for the somatic antigen specificity of these organisms. The chemical composition of these side chains both with respect to components and arrangement of the different su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Legionella Pneumophila
''Legionella pneumophila'' is a thin, aerobic, pleomorphic, flagellated, non-spore-forming, Gram-negative bacterium of the genus '' Legionella''. ''L. pneumophila'' is the primary human pathogenic bacterium in this group and is the causative agent of Legionnaires' disease, also known as legionellosis. In nature, ''L. pneumophila'' infects freshwater and soil amoebae of the genera '' Acanthamoeba'' and '' Naegleria''. The mechanism of infection is similar in amoeba and human cells. Characterization ''L. pneumophila'' is a Gram-negative, non-encapsulated, aerobic bacillus with a single, polar flagellum often characterized as being a coccobacillus. It is aerobic and unable to hydrolyse gelatin or produce urease. It is also non- fermentative. ''L. pneumophila'' is neither pigmented nor does it autofluoresce. It is oxidase- and catalase-positive, and produces beta-lactamase. ''L. pneumophila'' colony morphology is gray-white with a textured, cut-glass appearance; it also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pontiac Fever
Pontiac fever is an acute, nonfatal respiratory disease caused by various species of Gram-negative bacteria in the genus ''Legionella''. It causes a mild upper respiratory infection that resembles acute influenza. Pontiac fever resolves spontaneously and often goes undiagnosed. Both Pontiac fever and the more severe Legionnaire's disease may be caused by the same bacteria, but Pontiac fever does not include pneumonia. Cause Species of ''Legionella'' known to cause Pontiac fever include ''Legionella pneumophila'', ''Legionella longbeachae'', '' Legionella feeleii'', '' Legionella micdadei'', and ''Legionella anisa''. Sources of the causative agents are aquatic systems and potting soil. The first outbreak caused by inhalation of aerosolized potting soil was discovered in New Zealand in January 2007. A total of 10 workers at a nursery came down with Pontiac fever. It was the first identification of ''L. longbeachae''. Pontiac fever does not spread from person to person. It is acquired ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Legionnaires' Disease
Legionnaires' disease is a form of atypical pneumonia caused by any species of '' Legionella'' bacteria, quite often ''Legionella pneumophila''. Signs and symptoms include cough, shortness of breath, high fever, muscle pains, and headaches. Nausea, vomiting, and diarrhea may also occur. This often begins 2–10 days after exposure. A legionellosis is any disease caused by ''Legionella'', including Legionnaires' disease (a pneumonia), Pontiac fever (a nonpneumonia illness), and Pittsburgh pneumonia, but Legionnaires' disease is the most common, so mentions of legionellosis often refer to Legionnaires' disease. The bacterium is found naturally in fresh water. It can contaminate hot water tanks, hot tubs, and cooling towers of large air conditioners. It is usually spread by breathing in mist that contains the bacteria. It can also occur when contaminated water is aspirated. It typically does not spread directly between people, and most people who are exposed do not become in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Victoria, Australia
Victoria is a state in southeastern Australia. It is the second-smallest state with a land area of , the second most populated state (after New South Wales) with a population of over 6.5 million, and the most densely populated state in Australia (28 per km2). Victoria is bordered by New South Wales to the north and South Australia to the west, and is bounded by the Bass Strait to the south (with the exception of a small land border with Tasmania located along Boundary Islet), the Great Australian Bight portion of the Southern Ocean to the southwest, and the Tasman Sea (a marginal sea of the South Pacific Ocean) to the southeast. The state encompasses a range of climates and geographical features from its temperate coastal and central regions to the Victorian Alps in the northeast and the semi-arid north-west. The majority of the Victorian population is concentrated in the central-south area surrounding Port Phillip Bay, and in particular within the metropolitan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Legionella
''Legionella'' is a genus of pathogenic gram-negative bacteria that includes the species '' L. pneumophila'', causing legionellosis (all illnesses caused by ''Legionella'') including a pneumonia-type illness called Legionnaires' disease and a mild flu-like illness called Pontiac fever. ''Legionella'' may be visualized with a silver stain or cultured in cysteine-containing media such as buffered charcoal yeast extract agar. It is common in many environments, including soil and aquatic systems, with at least 50 species and 70 serogroups identified. These bacteria, however, are not transmissible from person to person; furthermore, most people exposed to the bacteria do not become ill. Most outbreaks are traced to poorly maintained cooling towers. The side chains of the cell wall carry the bases responsible for the somatic antigen specificity of these organisms. The chemical composition of these side chains both with respect to components and arrangement of the different sugars d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleomorphism
{{disambiguation ...
Pleomorphism may refer to: * Pleomorphism (cytology), variability in the size and shape of cells and/or their nuclei * Pleomorphism (microbiology), the ability of some bacteria to alter their shape or size in response to environmental conditions * A life cycle of certain fungi where different stages have different morphology, see Teleomorph, anamorph and holomorph In mycology, the terms teleomorph, anamorph, and holomorph apply to portions of the life cycles of fungi in the phyla Ascomycota and Basidiomycota: *Teleomorph: the sexual reproductive stage (morph), typically a fruiting body. *Anamorph: an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagella
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] |
