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List Of Microorganisms Tested In Outer Space
The survival of some microorganisms exposed to outer space has been studied using both simulated facilities and low Earth orbit exposures. Bacteria were some of the first organisms investigated, when in 1960 a Russian satellite carried ''Escherichia coli'', '' Staphylococcus'', and ''Enterobacter aerogenes'' into orbit. Many kinds of microorganisms have been selected for exposure experiments since, as listed in the table below. Experiments of the adaption of microbes in space have yielded unpredictable results. While sometimes the microorganism may weaken, they can also increase in their disease-causing potency. It is possible to classify these microorganisms into two groups, the human-borne and the extremophiles. Studying the human-borne microorganisms is significant for human welfare and future crewed missions in space, whilst the extremophiles are vital for studying the physiological requirements of survival in space. NASA has pointed out that normal adults have ten times as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microorganisms
A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in older texts. The informal synonym ''microbe'' () comes from μικρός, mikrós, "small" and βίος, bíos, "life". is an organism of microscopic size, which may exist in its single-celled form or as a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from sixth century BC India. The scientific study of microorganisms began with their observation under the microscope in the 1670s by Anton van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera, diphtheria, and anthrax. Because micr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spore
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes. Two gametes fuse to form a zygote which develops into a new s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Megaterium
''Bacillus megaterium'' is a rod-like, Gram-positive, mainly aerobic spore forming bacterium found in widely diverse habitats.De Vos, P. ''et al.'' Bergey's Manual of Systematic Bacteriology: Volume 3: The Firmicutes. ''Springer'' (2009) It has a cell length of up to 4 µm and a diameter of 1.5 µm, which is quite large for a bacteria. The cells often occur in pairs and chains, where the cells are joined together by polysaccharides on the cell walls. In the 1960s, prior to the utilization of ''Bacillus subtilis'' for this purpose, ''B. megaterium'' was the main model organism among Gram-positive bacteria for intensive studies on biochemistry, sporulation and bacteriophages. Recently, its popularity has started increasing in the field of biotechnology for its recombinant protein production capacity.Bunk, B. ''et al.'' A short story about a big magic bug. ''Bioengineered Bugs'' 1:85–91 (2010) This species has been recently transferred into the genus ''Priestia''. The c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus Cereus
''Bacillus cereus'' is a Gram-positive rod-shaped bacterium commonly found in soil, food, and marine sponges. The specific name, ''cereus'', meaning "waxy" in Latin, refers to the appearance of colonies grown on blood agar. Some strains are harmful to humans and cause foodborne illness due to their spore-forming nature, while other strains can be beneficial as probiotics for animals, and even exhibit mutualism with certain plants. ''B. cereus'' bacteria may be anaerobes or facultative anaerobes, and like other members of the genus ''Bacillus'', can produce protective endospores. They have a wide range of virulence factors, including phospholipase C, cereulide, sphingomyelinase, metalloproteases, and cytotoxin K, many of which are regulated via quorum sensing. ''B. cereus'' strains exhibit flagellar motility. The ''Bacillus cereus'' group comprises seven closely related species: ''B. cereus'' ''sensu stricto'' (referred to herein as ''B. cereus''), '' B. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azotobacter Vinelandii
''Azotobacter vinelandii'' is Gram-negative diazotroph that can fix nitrogen while grown aerobically. These bacteria are easily cultured and grown. ''A. vinelandii'' is a free-living N2 fixer known to produce many phytohormones and vitamins in soils. It produces fluorescent pyoverdine pigments. Nitrogenase The nitrogenase holoenzyme of ''A. vinelandii'' has been characterised by X-ray crystallography in both ADP tetrafluoroaluminate-bound and Mg ATP-bound states. The enzyme possesses molybdenum iron- sulfido cluster cofactors (FeMoco) as active sites, each bearing two pseudocubic iron-sulfido structures. Applications It is a genetically tractable system that is used to study nitrogen fixation. Genetically engineered strains can produce significantly higher amounts of ammonia. Appropriate ammonia emissions can provide crops with the ammonia they need without excess amounts that can pollute lakes and oceans. Variable ploidy ''A. vinelandii'' can contain up to 80 chr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azotobacter Chroococcum
''Azotobacter chroococcum'' is a bacterium that has the ability to fix atmospheric nitrogen. It was discovered by Martinus Beijerinck in 1901, and was the first aerobic, free-living nitrogen fixer discovered. ''A. chroococcum'' could be useful for nitrogen fixation in crops as a biofertilizer, fungicide, and nutrient indicator, and in bioremediation. Characteristics ''A. chroococcum'' is a microaerophilic plant growth-promoting rhizobacterium (PGRP), which is bacillus in shape and is Gram negative. As a mesophile, this bacterium grows best in moderate-temperature soils and requires a neutral pH environment. It is able to fix nitrogen under aerobic conditions. The soil cannot be poor in phosphorus or else nitrogen fixing can be hindered. In addition to phosphorus, these bacteria needed potassium, "sulphur, magnesium, and calcium" to grow. To fix nitrogen ''A. chroococcum'' produces three enzymes (catalase, peroxidase, and superoxide dismutase) to "neutralise" reactive oxygen s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anabaena Cylindrica
''Anabaena'' is a genus of filamentous cyanobacteria that exist as plankton. They are known for nitrogen-fixing abilities, and they form symbiotic relationships with certain plants, such as the mosquito fern. They are one of four genera of cyanobacteria that produce neurotoxins, which are harmful to local wildlife, as well as farm animals and pets. Production of these neurotoxins is assumed to be an input into its symbiotic relationships, protecting the plant from grazing pressure. A DNA sequencing project was undertaken in 1999, which mapped the complete genome of ''Anabaena'', which is 7.2 million base pairs long. The study focused on heterocysts, which convert nitrogen into ammonia. Certain species of ''Anabaena'' have been used on rice paddy fields, proving to be an effective natural fertilizer. Nitrogen fixation by ''Anabaena'' Under nitrogen-limiting conditions, vegetative cells differentiate into heterocysts at semiregular intervals along the filaments. Heterocyst c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aeromonas Proteolytica
''Aeromonas'' is a genus of Gram-negative, facultative anaerobic, rod-shaped bacteria that morphologically resemble members of the family Enterobacteriaceae. Most of the 14 described species have been associated with human diseases. The most important pathogens are '' A. hydrophila'', '' A. caviae'', and '' A. veronii'' biovar ''sobria''. The organisms are ubiquitous in fresh and brackish water. They group with the gamma subclass of the Proteobacteria. Two major diseases associated with ''Aeromonas'' are gastroenteritis and wound infections, with or without bacteremia. Gastroenteritis typically occurs after the ingestion of contaminated water or food, whereas wound infections result from exposure to contaminated water. In its most severe form, ''Aeromonas'' spp. can cause necrotizing fasciitis, which is life-threatening, usually requiring treatment with antibiotics and even amputation. Although some potential virulence factors (e.g. endotoxins, hemolysins, enterotoxins, adherenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinomyces Erythreus
''Saccharopolyspora erythraea'' is a species of actinomycete bacteria within the genus ''Saccharopolyspora''. ''Saccharopolyspora erythraea'' produces the macrolide antibiotic erythromycin. Cytochrome P450 Cytochromes P450 (CYPs) are a Protein superfamily, superfamily of enzymes containing heme as a cofactor (biochemistry), cofactor that functions as monooxygenases. In mammals, these proteins oxidize steroids, fatty acids, and xenobiotics, and are ... eryF (CYP107A1) originally from the bacterium is responsible for the biosynthesis of the antibiotic by C6-hydroxylation of the macrolide 6-deoxyerythronolide B. Small non-coding RNAs have been suggested to be involved in regulation of the secondary metabolite biosynthesis. References External linksType strain of ''Saccharopolyspora erythraea'' at Bac''Dive'' - the Bacterial Diversity Metadatabase Pseudonocardineae {{Pseudonocardineae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spores
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes. Two gametes fuse to form a zygote which develops into a new spor ... [...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] |
Impact Event
An impact event is a collision between astronomical objects causing measurable effects. Impact events have physical consequences and have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or meteoroids and have minimal effect. When large objects impact terrestrial planets such as the Earth, there can be significant physical and biospheric consequences, though atmospheres mitigate many surface impacts through atmospheric entry. Impact craters and Impact structure, structures are dominant landforms on many of the Solar System's solid objects and present the strongest empirical evidence for their frequency and scale. Impact events appear to have played a significant role in the Formation and evolution of the Solar System, evolution of the Solar System since its formation. Major impact events have significantly shaped History of the Earth, Earth's history, and have been implicated in the giant impact theory, formation of the Earth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
