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| {{Biorealm Genus}} | | {{Escherichia coli O157:H7}} |
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| [[Image:chroococcussmall.jpg|frame|right|''Chroococcus turgidus''. Image courtesy of [http://micro.magnet.fsu.edu/featuredmicroscopist/vanegmond/galleryindex.html Wim van Edmond]. Copyright 2000-2005.]] | | [[''Escherichia coli O157:H7''. Image courtesy of [http://www.about-ecoli.com/E-bug.gif OutBreak, Inc]. Copyright 2005 - 2007.]] |
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| ==Classification== | | ==Classification== |
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| ===Higher order taxa:===
| | Phylum: Proteobacteria |
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| | Class: Gamma Proteobacteria |
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| | Order: Enterobacteriales |
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| | Family: Enterobacteriaceae |
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| | Genus: Escherichia |
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| | Species: E. coli |
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| Bacteria; Cyanobacteria; Chroococcales
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| ===Species:=== | | ==Description== |
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| ''Chroococcus dispersus, C. submarinus, C. submarinus kopara-BM, C. turgidus''
| | Escherichia coli O157:H7 is an enterohemorrhagic strain of the bacterium Escherichia coli.[1] Escherichia coli O157:H7 is one of the four recognized classes of enterovirulent E. coli which can cause gastroenteritis in human. |
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| '''NCBI: [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=70190&lvl=3&lin=f&keep=1&srchmode=1&unlock Taxonomy] Genome'''
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| ==Description and Significance==
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| ''Chroococcus'', a unicellular organism that is a genus of cyanobacteria, is blue-green in color and macroscopic colony mounded. Within the outside sheath, microscopic colonies are found with indistinct trichomes. ''Chroococcus'' are usually found in colonies of two, four, or eight cells with a transparent protective covering sheath containing photosynthetic pigments. Like all cyanobacteria, ''Chroococcus'' is a prokaryote and therefore lacks any of the membranous organelles of eukaryotes. Known for its underwater habitat, ''Chroococcus'' prefers the sludge of lake and river bottoms to call home.
| | ==Unique characteristics== |
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| ''Chroococcus'', like other cyanobacteria, has signifanct ecological implications as a productive microbe. ''Chroococcus'' uses an extensive quantity of atmospheric carbon for photosynthetic processes, creating free oxygen in the atmosphere. In addition, ''Chroococcus'' is part of the first genus to use water to access electrons and hydrogen for photosynthesis, which also produces more free oxygen to be used by other organisms.
| | Escherichia coli O157:H7 has some Unique characteristics: c |
| | Cannot metabolize sorbitol |
| | Poor growth at 44-45.5 °C |
| | Lacking beta-glucuronidase activity |
| | Tolerates low pH well [2] |
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| ==Genome Structure==
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| Relatively few studies have been performed on the background genetics of ''Chroococcus'' as of yet. Although there are currently no known genome sequencing projects, there is hope of one beginning soon because of ''Chroococcus's'' significant implications as an oxygen production source.
| | ==Toxicity== |
| | E. coli O157:H7 infection often causes severe bloody diarrhea and abdominal cramps; sometimes the infection causes non-bloody diarrhea or no symptoms. Vomiting occurs in about half of persons and fever, usually not high, occurs less than one-third of the time. On the second or third day of illness, stools may become bloody in 30% to 75% of cases. The illness resolves in 5 to 10 days. Infants and the elderly are most susceptible. The incubation period is usually 3-4 days, although rarely the incubation can be as short as 12 hours or as long as 8 days. Most of the time there is no long-term effects. Asymptomatic infection can occur.[3] |
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| ==Cell Structure and Metabolism==
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| [[Image:Chroococcus.JPG|frame|left|''Chroococcus sp.'' Image courtesy of Dr. Morgan Vis of [http://vis-pc.plantbio.ohiou.edu/algaeindex.htm Ohio University.]]]
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| ''Chroococcus''cells are ovoid or rod-shaped unicells with a diametere ranging between 0.4 to 40µm (Ditty). Formerly thought of and named as a blue-green strain of algae, cyanobacteria shares a close resemblance with green eukaryotic algae. In addition to physical similarities, cynaobacteria and algae also share similar habitats, often growing together.
| | ==Treatment== |
| | Antibiotics are not used with this type of infection. Most people usually recovery within five to 10 days. Sometimes people will develop hemolytic uremic syndrome (HUS),life-threatening disease. Blood transfusions and kidney dialysis can treat HUS. |
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| ''Chroococcus''is an autotrophic organism able to survive almost without any freshwater or oxygen source (Carboni). ''Chroococcus''produces oxygen and adenosine triphosphate through phtosynthetic methods using sunlight as the catalyst.
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| ==Ecology==
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| ''Chroococcus ''is known to traditionally inhabit freshwater areas, but has also been identified in water sources of higher salinity. ''Chroococcus ''has also been found in plankton inhabiting water reserves (Komárek). ''Chroococcus ''is often incorrectly identified, therefore outlining a true habitat pattern is difficult.
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| ==References== | | ==References== |
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| [http://www.funsci.com/fun3_en/microw/microw.htm Carboni, G. Microworlds. Nov 2004.]
| | 1. Karch H, Tarr P, Bielaszewska M (2005). Enterohaemorrhagic Escherichia coli in human medicine. Int J Med Microbiol 295 (6-7): 405–18. PMID 16238016. |
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| [http://micro.magnet.fsu.edu/featuredmicroscopist/vanegmond/chroococcussmall.html Davidson, M.W. Molecular Expressions: Featured Microscopist: Wim van Egmond. 01 Dec 2003.]
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| [http://courses.biology.utah.edu/williams/3370/annurev.genet.37.110801.pdf Ditty, J.L., S.B. Williams, and S.S. Golden. "A Cyanobacterial Circadian Timing Mechanism.Annu. Rev. Genet. 2003. 37: 513-43.]
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| [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=16233836&dopt=Abstract Hong J, Ma H, Otaki M."Controlling algal growth in photo-dependent decolorant sludge by photocatalysis." <span title="Journal of bioscience and bioengineering.">J Biosci Bioeng.</span> 2005 Jun;99(6):592-7.]
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| [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11575503&query_hl=3&itool=pubmed_DocSum Kirkwood AE, Nalewajko C, Fulthorpe RR."The occurrence of cyanobacteria in pulp and paper waste-treatment systems." <span title="Canadian journal of microbiology.">Can J Microbiol.</span> 2001 Aug;47(8):761-6. ]<br /><br />[http://www.cyanodb.cz/Chroococcus/Chroococcus.html Komárek, Jiří and Tomáš Hauer.1992. CyanoDB: The online database of cyanobacterial genera. Database of cyanoprokaryotes: Databse of Genera.]
| | 2. Geoff Copper, Rebecca Young, Claire Campbell,. Guyton Durnin, Linha Phan, Leah McKay. (2006) Escherichia coli O157:H7 |
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| [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12744080&query_hl=3&itool=pubmed_DocSum Rezanka T, Dor I, Prell A, Dembitsky VM."Fatty acid composition of six freshwater wild cyanobacterial species." <span title="Folia microbiologica.">Folia Microbiol (Praha).</span> 2003;48(1):71-5.]
| | 3. CALVIN B. JOHNSON (2006).Escherichia coli O157:H7 (E. Coli) |
Template:Escherichia coli O157:H7
[[Escherichia coli O157:H7. Image courtesy of OutBreak, Inc. Copyright 2005 - 2007.]]
Classification
Phylum: Proteobacteria
Class: Gamma Proteobacteria
Order: Enterobacteriales
Family: Enterobacteriaceae
Genus: Escherichia
Species: E. coli
Description
Escherichia coli O157:H7 is an enterohemorrhagic strain of the bacterium Escherichia coli.[1] Escherichia coli O157:H7 is one of the four recognized classes of enterovirulent E. coli which can cause gastroenteritis in human.
Unique characteristics
Escherichia coli O157:H7 has some Unique characteristics: c
Cannot metabolize sorbitol
Poor growth at 44-45.5 °C
Lacking beta-glucuronidase activity
Tolerates low pH well [2]
Toxicity
E. coli O157:H7 infection often causes severe bloody diarrhea and abdominal cramps; sometimes the infection causes non-bloody diarrhea or no symptoms. Vomiting occurs in about half of persons and fever, usually not high, occurs less than one-third of the time. On the second or third day of illness, stools may become bloody in 30% to 75% of cases. The illness resolves in 5 to 10 days. Infants and the elderly are most susceptible. The incubation period is usually 3-4 days, although rarely the incubation can be as short as 12 hours or as long as 8 days. Most of the time there is no long-term effects. Asymptomatic infection can occur.[3]
Treatment
Antibiotics are not used with this type of infection. Most people usually recovery within five to 10 days. Sometimes people will develop hemolytic uremic syndrome (HUS),life-threatening disease. Blood transfusions and kidney dialysis can treat HUS.
References
1. Karch H, Tarr P, Bielaszewska M (2005). Enterohaemorrhagic Escherichia coli in human medicine. Int J Med Microbiol 295 (6-7): 405–18. PMID 16238016.
2. Geoff Copper, Rebecca Young, Claire Campbell,. Guyton Durnin, Linha Phan, Leah McKay. (2006) Escherichia coli O157:H7
3. CALVIN B. JOHNSON (2006).Escherichia coli O157:H7 (E. Coli)
