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| {{Redirect|E. coli|the protozoan parasite|Entamoeba coli}}
| | #REDIRECT [[Escherichia coli]] |
| {{Taxobox
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| | color = lightgrey
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| | name = ''Escherichia coli''
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| | status =
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| | image = EscherichiaColi NIAID.jpg
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| | image_width = 250px
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| | Domain = [[Bacteria]]
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| | phylum = [[Proteobacteria]]
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| | classis = [[Proteobacteria|Gamma Proteobacteria]]
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| | ordo = [[Enterobacteriaceae|Enterobacteriales]]
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| | familia = [[Enterobacteriaceae]]
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| | genus = ''[[Escherichia]]''
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| | species = '''''E. coli'''''
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| | binomial = ''Escherichia coli''
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| | binomial_authority = ([[Walter Migula|Migula]] 1895)<br>[[Castellani]] and [[Chalmers]] 1919
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| }}
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| {{SI}}
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| {{EH}}
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| '''''Escherichia coli''''' (commonly '''''E. coli'''''; {{pronEng|ˌɛʃ<s>ɪ</s>ˈrɪkiə ˈkoʊlaɪ}}, {{IPA|/iː ~/}}, and named for [[Theodor Escherich|its discoverer]]), is a [[Gram negative]] [[bacterium]] that is commonly found in the lower [[gastrointestinal tract|intestine]] of warm-blooded animals. Most ''E. coli'' [[Strain (biology)|strain]]s are harmless, but some, such as [[serovar|serotype]] [[Escherichia coli O157:H7|O157:H7]], can cause serious [[Foodborne illness|food poisoning]] in humans, and are occasionally responsible for costly [[product recall]]s.<ref name=CDC>{{cite web | title=''Escherichia coli'' O157:H7| work=CDC Division of Bacterial and Mycotic Diseases | url=http://www.cdc.gov/ncidod/dbmd/diseaseinfo/escherichiacoli_g.htm | accessdate=2007-01-25}}</ref><ref name="Vogt">{{cite journal |last=Vogt |first=R.L. |coauthors=L. Dippold |year=2005 |month=Mar-Apr |title=''Escherichia coli'' O157:H7 outbreak associated with consumption of ground beef, June-July 2002 |journal=Public Health Reports |volume=2 |issue= |pages=174–178 |id= |url= |accessdate= |quote= }} PMID 15842119.</ref> The harmless [[Strain (biology)|strains]] are part of the [[Human flora|normal flora]] of the [[gut]], and can benefit their hosts by producing [[vitamin K|vitamin K<sub>2</sub>]],<ref name="Bentley">Bentley, R, Meganathan, R., Biosynthesis of Vitamin K (menaquinone) in Bacteria, ''Bacteriological Reviews'', 1982, 46(3):241-280. Review. </ref> or by preventing the establishment of [[pathogen]]ic bacteria within the intestine.<ref name="Hudault">Hudault, S.; J. Guignot and A.L. Servin (July 2001). "''Escherichia coli'' strains colonizing the gastrointestinal tract protect germfree mice against ''Salmonella typhimurium'' infection." ''Gut'' '''49''':47-55. PMID 11413110.</ref><ref name="Reid">Reid, G.; J. Howard and B.S. Gan (September 2001). "Can bacterial interference prevent infection?" ''Trends in Microbiology'' '''9'''(9):424-428. PMID 11553454.</ref>
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| ''E. coli'' are not always confined to the intestine, and their ability to survive for brief periods outside the body makes them an ideal [[indicator organism]] to test environmental samples for [[Feces|fecal contamination]].<ref name="Feng_2002"/><ref name="Thompson">{{cite news |first=Andrea |last=Thompson |title=E. coli Thrives in Beach Sands |url=http://www.livescience.com/health/070604_beach_ecoli.html |work= |publisher=Live Science |date=2007-06-04 |accessdate=2007-12-03 }}</ref> The bacteria can also be grown easily and its [[genetics]] are comparatively simple and easily-manipulated, making it one of the best-studied prokaryotic [[model organism]]s, and an important species in [[biotechnology]] and [[microbiology]]. ''E. coli'' was discovered by German pediatrician and bacteriologist [[Theodor Escherich]] in 1885,<ref name="Feng_2002">{{cite web | author = Feng P, Weagant S, Grant, M | title=Enumeration of ''Escherichia coli'' and the Coliform Bacteria | work=Bacteriological Analytical Manual (8th ed.) | publisher = FDA/Center for Food Safety & Applied Nutrition | date= 2002-09-01 | url=http://www.cfsan.fda.gov/~ebam/bam-4.html | accessdate=2007-01-25}}</ref> and is now classified as part of the [[Enterobacteriaceae]] family of [[Proteobacteria|gamma-proteobacteria]].<ref>{{cite web |url=http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Tree&id=561&lvl=3&lin=f&keep=1&srchmode=1&unlock |title=''Escherichia'' |accessdate=2007-11-30 |last= |first= |coauthors= |date= |work=Taxonomy Browser |publisher=NCBI}}</ref>
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| == Strains ==
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| [[Image:Life cycle of Escherichia coli.png|thumb|right|Model of successive binary fission in ''E. coli'']]
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| A [[strain (biology)|strain]] of ''E. coli'' is a sub-group within the species that has unique characteristics that distinguish it from other ''E. coli'' strains. These differences are often detectable only on the molecular level; however, they may result in changes to the physiology or lifecycle of the bacterium. For example, a strain may gain [[pathogenicity|pathogenic capacity]], the ability to use a unique carbon source, the ability to inhabit a particular ecological niche or the ability to resist antimicrobial agents. Different strains of ''E. coli'' are often host-specific, making it possible to determine the source of fecal contamination in environmental samples.<ref name="Feng_2002"/><ref name="Thompson"/> Depending on which ''E. coli'' strains are present in a water sample, for example, assumptions can be made about whether the contamination originated from a human, other mammal or bird source.
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| New strains of ''E. coli'' [[evolution|evolve]] through the natural biological process of [[mutation]], and some strains develop [[trait]]s that can be harmful to a host animal. Although virulent strains typically cause no more than a bout of diarrhea in healthy adult humans, particularly virulent strains, such as [[Escherichia coli O157:H7|O157:H7]] or [[O111:B4]], can cause serious illness or death in the elderly, the very young or the [[immunocompromised]].<ref name="Hudault">Viljanen, M.K.; T. Peltola, S.Y. Junnila, L. Olkkonen, H. Järvinen, M. Kuistila and P. Huovinen (October 6, 1990). "Outbreak of diarrhoea due to ''Escherichia coli'' O111:B4 in schoolchildren and adults: association of Vi antigen-like reactivity." ''Lancet'' '''336'''(8719):831-834. PMID 1976876.</ref>
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| == Biology and biochemistry ==
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| [[Image:Ecoli flagellum.jpg|thumb|350px|Escherichia coli cells propel themselves with flagella (long, thin structures) arranged as bundles that rotate counter-clockwise, generating torque to rotate the bacterium clockwise.]]
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| ''E. coli'' is [[Gram-negative bacteria|Gram-negative]], [[Facultative anaerobic organism|facultative anaerobic]] and [[Endospore|non-sporulating]]. Cells are typically rod-shaped and are about 2 [[micrometre]]s (μm) long and 0.5 μm in diameter, with a cell volume of 0.6 - 0.7 μm<sup>3</sup>.<ref>{{cite journal |author=Kubitschek HE |title=Cell volume increase in Escherichia coli after shifts to richer media |journal=J. Bacteriol. |volume=172 |issue=1 |pages=94–101 |year=1990 |month=January |pmid=2403552 |pmc=208405 |url=http://jb.asm.org/cgi/pmidlookup?view=long&pmid=2403552}}</ref> It can live on a wide variety of substrates. ''E. coli'' uses mixed-acid fermentation in anaerobic conditions, producing [[lactic acid|lactate]], [[succinate]], [[ethanol]], [[acetate]] and carbon dioxide. Since many pathways in mixed-acid fermentation produce hydrogen gas, these pathways require the levels of hydrogen to be low, as is the case when ''E. coli'' lives together with hydrogen-consuming organisms such as [[methanogen]]s or [[sulfate-reducing bacteria]].<ref>{{cite book | title=Brock Biology of microorganisms| author=Madigan MT, Martinko JM| year=2006| publisher=Pearson| isbn=0-13-196893-9| edition=11th ed.}}</ref>
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| Optimal growth of ''E. coli'' occurs at 37°C, but some laboratory strains can multiply at temperatures of up to 49°C.<ref>{{cite journal |author=Fotadar U, Zaveloff P, Terracio L |title=Growth of Escherichia coli at elevated temperatures |journal=J. Basic Microbiol. |volume=45 |issue=5 |pages=403–4 |year=2005 |pmid=16187264 | doi = 10.1002/jobm.200410542 }}</ref> Growth can be driven by aerobic or anaerobic respiration, using a large variety of [[redox|redox pairs]], including the oxidation of [[pyruvic acid]], [[formic acid]], [[hydrogen]] and [[amino acid]]s, and the reduction of substrates such as [[oxygen]], [[nitrate]], [[dimethyl sulfoxide]] and [[trimethylamine N-oxide]].<ref name=Ingledew>{{cite journal |author=Ingledew WJ, Poole RK |title=The respiratory chains of Escherichia coli |journal=Microbiol. Rev. |volume=48 |issue=3 |pages=222–71 |year=1984 |pmid=6387427}}</ref>
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| Strains that possess [[flagellum|flagella]] can swim and are [[motile]], but other strains lack flagellum. The flagella of ''E. coli'' have a [[Flagellum#Flagella arrangement schemes|peritrichous]] arrangement.<ref>Darnton NC, Turner L, Rojevsky S, Berg HC, On torque and tumbling in swimming Escherichia coli. J Bacteriol. 2007 Mar;189(5):1756-64. Epub 2006 Dec 22.</ref>
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| ''E. coli'' and related bacteria possess the ability to transfer [[DNA]] via [[bacterial conjugation]], [[transduction (genetics)|transduction]] or [[transformation (genetics)|transformation]], which allows genetic material to [[Horizontal gene transfer|spread horizontally]] through an existing population. This process led to the spread of the gene encoding [[shiga toxin]] from ''[[Shigella]]'' to ''E. coli'' O157:H7, carried by a [[bacteriophage]].<ref>{{cite journal |author=Brüssow H, Canchaya C, Hardt WD |title=Phages and the evolution of bacterial pathogens: from genomic rearrangements to lysogenic conversion |journal=Microbiol. Mol. Biol. Rev. |volume=68 |issue=3 |pages=560–602 |year=2004 |month=September |pmid=15353570 |pmc=515249 |doi=10.1128/MMBR.68.3.560-602.2004 |url=http://mmbr.asm.org/cgi/pmidlookup?view=long&pmid=15353570}}</ref>
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| == Role as normal flora ==
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| ''E. coli'' normally colonizes an infant's [[gastrointestinal tract]] within 40 hours of birth, arriving with food or water or with the individuals handling the child.
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| In the bowel, it adheres to the [[mucus]] of the [[large intestine]]. It is the primary [[Facultative anaerobic organism|facultative organism]] of the human gastrointestinal tract.<ref name="Todar" /> As long as these bacteria do not acquire [[bacteriophage|genetic elements]] encoding for [[virulence factor]]s, they remain benign [[Commensalism|commensals]].<ref name=Evans />
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| == Role in disease ==
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| Virulent strains of ''E. coli'' can cause [[gastroenteritis]], [[urinary tract infection]]s, and [[neonatal]] [[meningitis]]. In rarer cases, virulent strains are also responsible for [[Hemolytic-uremic syndrome|hæmolytic-uremic syndrome (HUS)]], [[peritonitis]], [[mastitis]], [[septicemia]] and Gram-negative [[pneumonia]].<ref name="Todar" />
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| === Gastrointestinal infection ===
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| [[Image:E coli at 10000x, original.jpg|thumb|right|250px|Low-temperature electron micrograph of a cluster of ''E. coli'' bacteria, magnified 10,000 times. Each individual bacterium is oblong shaped.]]
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| Certain strains of ''E. coli'', such as [[Escherichia coli O157:H7|O157:H7]], [[Escherichia coli O121|O121]] and [[Escherichia coli O104:H21|O104:H21]], produce [[toxin]]s. [[Food poisoning]] caused by ''E. coli'' are usually associated with eating unwashed vegetables and meat contaminated post-slaughter. O157:H7 is further notorious for causing serious and even life-threatening complications like [[hemolytic-uremic syndrome]] (HUS). This particular strain is linked to the [[2006 United States E. coli outbreak]] of fresh spinach. Severity of the illness varies considerably; it can be fatal, particularly to young children, the elderly or the immunocompromised, but is more often mild. ''E. coli'' can harbor both heat-stable and heat-labile enterotoxins. The latter, termed LT, contains one 'A' subunit and five 'B' subunits arranged into one holotoxin, and is highly similar in structure and function to [[Cholera]] toxins. The B subunits assist in adherence and entry of the toxin into host intestinal cells, while the A subunit is cleaved and prevents cells from absorbing water, causing [[diarrhea]]. LT is secreted by the Type 2 secretion pathway.<ref>{{cite journal |author=Tauschek M, Gorrell R, Robins-Browne RM, |title=Identification of a protein secretory pathway for the secretion of heat-labile enterotoxin by an enterotoxigenic strain of Escherichia coli | journal=PNAS | volume=99 |pages=7066-7071 | url=http://www.pnas.org/cgi/content/abstract/99/10/7066 | pmid = 12011463 | doi = 10.1073/pnas.092152899 }} </ref>
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| If ''E. coli'' bacteria escape the intestinal tract through a perforation (for example from an [[Peptic ulcer|ulcer]], a [[ruptured appendix]], or a [[surgical error]]) and enter the abdomen, they usually cause [[peritonitis]] that can be fatal without prompt treatment. However, ''E. coli'' are extremely sensitive to such [[antibiotics]] as [[streptomycin]] or [[gentamicin]]. This could change since, as noted below, ''E. coli'' quickly acquires drug resistance.<ref name=SciDaily_2001>{{cite web | title=Gene Sequence Of Deadly E. Coli Reveals Surprisingly Dynamic Genome | publisher=Science Daily | url=http://www.sciencedaily.com/releases/2001/01/010125082330.htm | date=2001-01-25 | accessdate=2007-02-08}}</ref>. Recent research suggests that treatment with antibiotics does not improve the outcome of the disease, and may in fact significantly increase the chance of developing haemolytic uraemic syndrome.<ref>{{cite journal |author=Wong CS, Jelacic S, Habeeb RL, et al. |title=Identification The risk of the hemolytic-uremic syndrome after antibiotic treatment of Escherichia coli O157:H7 infections.| journal=N Engl J Med | volume=342 (26) |pages=1930-6 }} </ref>
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| Intestinal mucosa-associated ''E. coli'' are observed in increased numbers in the [[inflammatory bowel disease]]s, [[Crohn's disease]] and [[ulcerative colitis]].<ref name="Rolhion">{{cite journal |author=Rolhion N, Darfeuille-Michaud A |title=Adherent-invasive Escherichia coli in inflammatory bowel disease |journal=Inflamm. Bowel Dis. |volume=13 |issue=10 |pages=1277–83 |year=2007 |pmid=17476674 |doi=10.1002/ibd.20176}}</ref> Invasive strains of ''E. coli'' exist in high numbers in the inflamed tissue, and the number of bacteria in the inflamed regions correlates to the severity of the bowel inflammation.<ref name="Baumgart">{{cite journal |author=Baumgart M, Dogan B, Rishniw M, ''et al'' |title=Culture independent analysis of ileal mucosa reveals a selective increase in invasive Escherichia coli of novel phylogeny relative to depletion of Clostridiales in Crohn's disease involving the ileum |journal=ISME J |volume=1 |issue=5 |pages=403–18 |year=2007 |pmid=18043660 |doi=10.1038/ismej.2007.52}}</ref>
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| ====Virulence properties==== <!-- Virulence properties of escherichia coli redirects here -->
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| Enteric ''E. coli'' (EC) are classified on the basis of serological characteristics and virulence properties.<ref name="Todar">{{cite web |url=http://www.textbookofbacteriology.net/e.coli.html |title=Pathogenic ''E. coli'' |accessdate=2007-11-30 |last=Todar |first=K. |coauthors= |date= |work=Online Textbook of Bacteriology |publisher=University of Wisconsin-Madison Department of Bacteriology}}</ref> Virotypes include:
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| {| class="wikitable"
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| ! Name
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| ! Hosts
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| ! Description
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| | [[Enterotoxigenic Escherichia coli|'''Enterotoxigenic ''E. coli''''']] (ETEC)
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| | causative agent of diarrhea (without fever) in humans, pigs, sheep, goats, cattle, dogs, and horses
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| | ETEC uses [[fimbria (bacteriology)|fimbrial adhesins]] (projections from the bacterial cell surface) to bind [[enterocyte]] cells in the [[small intestine]]. ETEC can produce two [[protein]]aceous [[enterotoxins]]:
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| * the larger of the two proteins, '''[[LT enterotoxin]]''', is similar to [[cholera toxin]] in structure and function.
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| * the smaller protein, '''[[ST enterotoxin]]''' causes [[Cyclic guanosine monophosphate|cGMP]] accumulation in the target cells and a subsequent secretion of fluid and electrolytes into the intestinal [[lumen (anatomy)|lumen]].
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| ETEC strains are non-invasive, and they do not leave the intestinal lumen. ETEC is the leading bacterial cause of diarrhea in children in the developing world, as well as the most common cause of [[traveler's diarrhea]]. Each year, ETEC causes more than 200 million cases of diarrhea and 380,000 deaths, mostly in children in developing countries.<ref>[http://www.who.int/vaccine_research/diseases/diarrhoeal/en/index4.html World Health Organization. Enterotoxigenic ''Escherichia coli'' (ETEC).]</ref>
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| | '''Enteropathogenic ''E. coli''''' (EPEC)
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| | causative agent of diarrhea in humans, rabbits, dogs, cats and horses
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| | Like ETEC, EPEC also causes diarrhea, but the molecular mechanisms of colonization and etiology are different. EPEC lack fimbriae, ST and LT toxins, but they utilize an [[adhesin]] known as [[intimin]] to bind host intestinal cells. This virotype has an array of virulence factors that are similar to those found in ''[[Shigella]]'', and may possess a [[shiga toxin]]. Adherence to the intestinal mucosa causes a rearrangement of [[actin]] in the host cell, causing significant deformation. EPEC cells are moderately-invasive (i.e. they enter host cells) and elicit an inflammatory response. Changes in intestinal cell ultrastructure due to "attachment and effacement" is likely the prime cause of diarrhea in those afflicted with EPEC.
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| | '''Enteroinvasive ''E. coli''''' (EIEC)
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| | found only in humans
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| | EIEC infection causes a syndrome that is identical to [[Shigellosis]], with profuse diarrhea and high fever. EIEC are highly invasive, and they utilize adhesin proteins to bind to and enter intestinal cells. They produce no toxins, but severely damage the intestinal wall through mechanical cell destruction.
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| | '''Enterohemorrhagic ''E. coli''''' (EHEC)
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| | found in humans, cattle, and goats
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| | The sole member of this virotype is strain [[O157:H7]], which causes bloody diarrhea and no fever. EHEC can cause [[hemolytic-uremic syndrome]] and sudden kidney failure. It uses bacterial fimbriae for attachment (E. coli common pilus, ECP),<ref>{{cite journal |last=Rendón |first=M. A. |authorlink= |coauthors=''et al.'' |year=2007 |month= |title=Commensal and pathogenic ''Escherichia coli'' use a common pilus adherence factor for epithelial cell colonization |journal=[[Proceedings of the National Academy of Sciences|PNAS]] |volume=104 |issue=25 |pages=10637–10642 |doi=10.1073/pnas.0704104104 |url= |accessdate= |quote= }}</ref> is moderately-invasive and possesses a phage-encoded Shiga toxin that can elicit an intense inflammatory response.
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| | '''Enteroaggregative ''E. coli''''' (EAggEC)
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| | found only in humans
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| | So named because they have fimbriae which aggregate [[tissue culture]] cells, EAggEC bind to the intestinal mucosa to cause watery diarrhea without fever. EAggEC are non-invasive. They produce a [[hemolysin]] and an ST enterotoxin similar to that of ETEC.
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| |}
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| ==== Epidemiology of gastrointestinal infection ====
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| Transmission of pathogenic ''E. coli'' often occurs via [[fecal-oral route|fecal-oral transmission]].<ref name="haccp">{{cite web |url=http://www.cfsan.fda.gov/~dms/hret2-a3.html |title=Retail Establishments; Annex 3 - Hazard Analysis |accessdate=2007-12-02 |last= |first= |coauthors= |month=April | year=2006 |work=Managing Food Safety: A Manual for the Voluntary Use of HACCP Principles for Operators of Food Service and Retail Establishments |publisher=U.S. Department of Health and Human Services Food and Drug Administration Center for Food Safety and Applied Nutrition}}</ref><ref name=Evans>{{cite web |url=http://www.gsbs.utmb.edu/microbook/ch025.htm |title=Escherichia Coli |accessdate=2007-12-02 |last=Evans Jr. |first=Doyle J. |coauthors=Dolores G. Evans |date= |work=Medical Microbiology, 4th edition |publisher=The University of Texas Medical Branch at Galveston}}</ref><ref>{{cite journal |last=Gehlbach |first=S.H. |coauthors=J.N. MacCormack, B.M. Drake, W.V. Thompson |year=1973 |month=April |title=Spread of disease by fecal-oral route in day nurseries |journal=Health Service Reports |volume=88 |issue=4 |pages=320–322 |pmid=4574421 |url= |quote= }}</ref> Common routes of transmission include: unhygienic food preparation,<ref name="haccp"/> farm contamination due to manure fertilization,<ref name="spinach">{{cite news |author=Sabin Russell |coauthors= |title=Spinach E. coli linked to cattle; Manure on pasture had same strain as bacteria in outbreak |url=http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2006/10/13/MNG71LOT711.DTL |publisher=San Francisco Chronicle |id= |date= October 13, 2006 |accessdate=2007-12-02 }}</ref> irrigation of crops with contaminated [[greywater]]
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| or raw [[sewage]],<ref>{{cite journal |author=Heaton JC, Jones K |title=Microbial contamination of fruit and vegetables and the behaviour of enteropathogens in the phyllosphere: a review |journal=J. Appl. Microbiol. |volume=104 |issue=3 |pages=613–26 |year=2008 |month=March |pmid=17927745 |doi=10.1111/j.1365-2672.2007.03587.x |url=http://www3.interscience.wiley.com/resolve/openurl?genre=article&sid=nlm:pubmed&issn=1364-5072&date=2008&volume=104&issue=3&spage=613}}</ref>
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| feral pigs on cropland,<ref name="DeGregori">{{cite web |author=Thomas R. DeGregori |year=2007-08-17|url= http://www.cgfi.org/cgficommentary/maddening-media-misinformation-on-biotech-and-industrial-agriculture-part-5-of-5 |title=CGFI: Maddening Media Misinformation on Biotech and Industrial Agriculture |accessdate=2007-12-08 |format= |work=}}</ref>
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| or direct consumption of sewage-contaminated water.<ref>{{cite journal |last=Chalmers |first=R.M. |coauthors=H. Aird, F.J. Bolton |year=2000 |month= |title=Waterborne ''Escherichia coli'' O157 |journal=Society for Applied Microbiology Symposium Series |volume= |issue=29 |pages=124S–132S |pmid=10880187}}</ref> Dairy and beef cattle are primary reservoirs of ''E. coli'' O157:H7,<ref name="bach"/> and they can carry it asymptomatically and shed it in their feces.<ref name="bach">{{cite journal |last=Bach |first=S.J. |coauthors=T.A. McAllister, D.M. Veira, V.P.J. Gannon, and R.A. Holley |year=2002 |month= |title=Transmission and control of ''Escherichia coli'' O157:H7 |journal=Canadian Journal of Animal Science |volume=82 |issue= |pages=475–490 |id= |url=http://pubs.nrc-cnrc.gc.ca/aic-journals/2002ab/cjas02/dec02/cjas02-021.html |accessdate= |quote= }}</ref> Food products associated with ''E. coli'' outbreaks include raw ground beef,<ref>{{cite book |last=Institute of Medicine of the National Academies |first= |authorlink= |coauthors= |editor= |others= |title=''Escherichia coli'' O157:H7 in Ground Beef: Review of a Draft Risk Assessment |url=http://www.nap.edu/catalog.php?record_id=10528 |edition= |series= |year=2002 |publisher=The National Academies Press |location=Washington, D.C. |isbn=0-309-08627-2 |pages= |chapter= |chapterurl= |quote= }}</ref> raw seed sprouts or spinach,<ref name="spinach"/> raw milk, unpasteurized juice, and foods contaminated by infected food workers via fecal-oral route.<ref name="haccp"/>
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| According to the [[U.S. Food and Drug Administration]], the fecal-oral cycle of transmission can be disrupted by cooking food properly, preventing cross-contamination, instituting barriers such as gloves for food workers, instituting health care policies so food industry employees seek treatment when they are ill, pasteurization of juice or dairy products and proper hand washing requirements.<ref name="haccp"/>
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| Shiga toxin-producing ''E. coli'' (STEC), specifically serotype O157:H7, have also been transmitted by flies,<ref>{{cite journal |author=Szalanski A, Owens C, McKay T, Steelman C |title=Detection of ''Campylobacter'' and ''Escherichia coli'' O157:H7 from filth flies by polymerase chain reaction |journal=Med Vet Entomol |volume=18 |issue=3 |pages=241-6 |year=2004 |url=http://www.blackwell-synergy.com/links/doi/10.1111/j.0269-283X.2004.00502.x/abs/ | pmid = 15347391 | doi = 10.1111/j.0269-283X.2004.00502.x }}</ref><ref>{{cite journal |author=Sela S, Nestel D, Pinto R, Nemny-Lavy E, Bar-Joseph M |title=Mediterranean fruit fly as a potential vector of bacterial pathogens |journal=Appl Environ Microbiol |volume=71 |issue=7 |pages=4052-6 |year=2005 |pmid = 16000820 | doi = 10.1128/AEM.71.7.4052-4056.2005 }}</ref><ref>{{cite journal |author=Alam M, Zurek L |title=Association of ''Escherichia coli'' O157:H7 with houseflies on a cattle farm |journal=Appl Environ Microbiol |volume=70 |issue=12 |pages=7578-80 |year=2004 |pmid=15574966 | doi = 10.1128/AEM.70.12.7578-7580.2004 }}</ref> as well as direct contact with farm animals,<ref>{{cite journal |last=Rahn |first=K. |coauthors=S.A. Renwick, R.P. Johnson, J.B. Wilson, R.C. Clarke, D. Alves, S.A. McEwen, H. Lior, J. Spika |title=Follow-up study of verocytotoxigenic Escherichia coli infection in dairy farm families |journal=Journal of Infectious Disease |volume=177 |issue=4 |pages=1139–1140 |year=1998 |month=April |pmid=9535003}}</ref><ref>{{cite journal |last=Trevena |first=W.B. |coauthors=G.A Willshaw, T. Cheasty, G. Domingue, C. Wray |title=Transmission of Vero cytotoxin producing ''Escherichia coli'' O157 infection from farm animals to humans in Cornwall and west Devon |journal=Community Disease and Public Health |volume=2 |issue=4 |pages=263–268 |year=1999 |month=December |pmid=10598383}}</ref> [[petting zoo]] animals,<ref>{{cite journal |last=Heuvelink |first=A.E. |coauthors=C. van Heerwaarden, J.T. Zwartkruis-Nahuis, R. van Oosterom, K. Edink, Y.T. van Duynhoven and E. de Boer |title=''Escherichia coli'' O157 infection associated with a petting zoo |journal=Epidemiology and Infection |volume=129 |issue=2 |pages=295-302 |year=2002 |month=October |pmid=12403105 | doi = 10.1017/S095026880200732X }}</ref> and airborne particles found in animal-rearing environments.<ref>{{cite journal |last=Varma |first=J.K. |coauthors=K.D. Greene, M.E. Reller, S.M. DeLong, J. Trottier, S.F. Nowicki, M. DiOrio, E.M. Koch, T.L. Bannerman, S.T. York, M.A. Lambert-Fair, J.G. Wells, P.S. Mead |title=An outbreak of ''Escherichia coli'' O157 infection following exposure to a contaminated building |journal=JAMA |volume=290 |issue=20 |pages=2709-2712 |year=2003 |month=November 26 |pmid=14645313 | doi = 10.1001/jama.290.20.2709 }}</ref>
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| === Urinary tract infection ===
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| Uropathogenic ''E. coli'' ('''UPEC''') is responsible for approximately 90% of [[urinary tract infection]]s (UTI) seen in individuals with ordinary anatomy.<ref name="Todar"/> In '''ascending infections''', fecal bacteria colonize the [[urethra]] and spread up the [[urinary tract]] to the [[bladder]] as well as to the [[kidneys]] (causing [[pyelonephritis]]),<ref>{{cite journal |author=Nicolle LE |title=Uncomplicated urinary tract infection in adults including uncomplicated pyelonephritis |journal=Urol. Clin. North Am. |volume=35 |issue=1 |pages=1–12, v |year=2008 |month=February |pmid=18061019 |doi=10.1016/j.ucl.2007.09.004}}</ref> or the [[prostate]] in males. Because women have a shorter urethra than men, they are 14-times more likely to suffer from an ascending UTI.<ref name="Todar"/>
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| Uropathogenic ''E. coli'' utilize P fimbriae ([[pyelonephritis]]-associated [[pili]]) to [[wikt:bind|bind]] urinary tract [[endothelial cell]]s and colonize the bladder. These [[wikt:adhesin|adhesin]]s specifically bind D-galactose-D-galactose [[moiety|moieties]] on the [[P blood]] group [[antigen]] of [[erythrocytes]] and [[uroepithelial]] cells.<ref name="Todar"/> Approximately 1% of the human population lacks this receptor, and its presence or absence dictates an individual's susceptibility to ''E. coli'' urinary tract infections. Uropathogenic ''E. coli'' produce [[Hemolysis (microbiology)|alpha- and beta-hemolysins]], which cause [[lysis]] of urinary tract cells.
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| UPEC can evade the body's innate immune defenses (e.g. the [[complement system]]) by invading superficial umbrella cells to form intracellular bacterial communities ([[IBC]]s).<ref>{{cite journal |author=Justice S, Hunstad D, Seed P, Hultgren S |title=Filamentation by Escherichia coli subverts innate defenses during urinary tract infection |journal=Proc Natl Acad Sci U S A |volume=103 |issue=52 |pages=19884-9 |year=2006 |pmid=17172451 | doi = 10.1073/pnas.0606329104 }}</ref> They also have the ability to form K antigen, capsular polysaccharides that contribute to [[biofilm]] formation. Biofilm-producing ''E. coli'' are recalcitrant to [[antibody|immune factors]] and [[antibiotic]] therapy and are often responsible for chronic urinary tract infections.<ref>{{cite journal |author=Ehrlich G, Hu F, Shen K, Stoodley P, Post J |title=Bacterial plurality as a general mechanism driving persistence in chronic infections |journal=Clin Orthop Relat Res |volume= |issue= |pages=20-4 |year=2005 |month=August |pmid=16056021 |url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=16056021 | doi = 10.1073/pnas.0606329104 }}</ref> K antigen-producing ''E. coli'' infections are commonly found in the upper urinary tract.<ref name="Todar"/>
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| '''Descending infections''', though relatively rare, occur when ''E. coli'' cells enter the upper urinary tract organs ([[kidney]]s, [[bladder]] or [[ureters]]) from the blood stream.
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| == Laboratory diagnosis ==
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| In stool samples microscopy will show [[Gram stain|Gram negative]] rods, with no particular cell arrangement. Then, either [[MacConkey agar]] or [[Eosin methylene blue|EMB agar]] (or both) are inoculated with the stool. On MacConkey agar, deep red colonies are produced as the organism is [[lactose]] positive, and fermentation of this sugar will cause the medium's [[pH]] to drop, leading to darkening of the medium. Growth on Levine EMB agar produces black colonies with greenish-black metallic sheen. This is diagnosic of ''E. coli''. The organism is also [[lysine]] positive, and grows on [[TSI slant]] with a (A/A/g+/H<sub>2</sub>S-) profile. Also, [[IMViC]] is ++-- for ''E. coli''; as it's [[indol]] positive (red ring) and [[methyl red]] positive (bright red), but VP negative (no change-colorless) and [[citrate]] negative (no change-green color). Tests for toxin production can use mammalian cells in [[tissue culture]], which are rapidly killed by [[shiga toxin]]. Although sensitive and very specific, this method is slow and expensive.<ref>{{cite journal |author=Paton JC, Paton AW |title=Pathogenesis and diagnosis of Shiga toxin-producing Escherichia coli infections |journal=Clin. Microbiol. Rev. |volume=11 |issue=3 |pages=450–79 |year=1998 |month=July |pmid=9665978 |pmc=88891 |url=http://cmr.asm.org/cgi/pmidlookup?view=long&pmid=9665978}}</ref>
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| Typically diagnosis has been done by culturing on sorbitol-MacConkey medium and then using typing antiserum. However, current latex assays and some typing antiserum have shown cross reactions with non-E. coli O157 colonies. Furthermore, not all E. coli O157 strains associated with HUS are nonsorbitol fermentors.
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| The Council of State and Territorial Epidemiologists recommend that clinical laboratories screen at least all bloody stools for this pathogen. The American Gastroenterological Association Foundation (AGAF) recommended in July 1994 that all stool specimens should be routinely tested for E. coli O157:H7.{{Fact|date=November 2008}} It is recommended that the clinician check with their state health department or the Centers for Disease Control and Prevention to determine which specimens should be tested and whether the results are reportable.
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| Other methods for detecting ''E. coli'' O157 in stool include [[ELISA]] tests, colony [[immunoblot]]s, direct immunofluorescence microscopy of filters, as well as immunocapture techniques using magnetic beads.<ref>{{cite journal |author=De Boer E, Heuvelink AE |title=Methods for the detection and isolation of Shiga toxin-producing Escherichia coli |journal=Symp Ser Soc Appl Microbiol |volume= |issue=29 |pages=133S–143S |year=2000 |pmid=10880188}}</ref> These assays are designed as screening tool to allow rapid testing for the presence of ''E. coli'' O157 without prior culturing of the stool specimen.
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| == Antibiotic therapy and resistance ==
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| {{Main|Antibiotic resistance}}
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| Bacterial infections are usually treated with [[antibiotic]]s. However, the antibiotic sensitivities of different strains of ''E. coli'' vary widely. As Gram-negative organisms, ''E. coli'' are resistant to many antibiotics that are effective against [[Gram-positive]] organisms. Antibiotics which may be used to treat ''E. coli'' infection include [[amoxicillin]] as well as other semi-synthetic penicillins, many [[cephalosporin]]s, [[carbapenems]], [[aztreonam]], [[trimethoprim-sulfamethoxazole]], [[ciprofloxacin]], [[nitrofurantoin]] and the [[aminoglycoside]]s.
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| [[Antibiotic resistance]] is a growing problem. Some of this is due to overuse of antibiotics in humans, but some of it is probably due to the use of antibiotics as growth promoters in food of animals.<ref name=Johnson_2006>{{cite journal |author=Johnson J, Kuskowski M, Menard M, Gajewski A, Xercavins M, Garau J |title=Similarity between human and chicken Escherichia coli isolates in relation to ciprofloxacin resistance status |journal=J Infect Dis |volume=194 |issue=1 |pages=71-8 |year=2006 |url=http://www.journals.uchicago.edu/JID/journal/issues/v194n1/35787/35787.html | pmid=16741884 | doi = 10.1086/504921 }}</ref> A study published in the journal [[Science (journal)|''Science'']] in August 2007 found that the rate of adaptative [[mutation]]s in ''E. coli'' is "on the order of 10<sup>–5</sup> per [[genome]] per generation, which is 1,000 times as high as previous estimates," a finding which may have significance for the study and management of bacterial antibiotic resistance.<ref>{{cite web
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| | url=http://www.sciencemag.org/cgi/content/abstract/317/5839/813?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=isabel+gordo&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT|title= Adaptive Mutations in Bacteria: High Rate and Small Effects|publisher=Science Magazine|date=[[10 August]] [[2007]]|dateformat=dmy|accessdate=[[10 September]] [[2007]]}}</ref>
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| Antibiotic-resistant ''E. coli'' may also pass on the genes responsible for antibiotic resistance to other species of bacteria, such as ''[[Staphylococcus aureus]]''. ''E. coli'' often carry multidrug resistant plasmids and under stress readily transfer those plasmids to other species. Indeed, ''E. coli'' is a frequent member of [[biofilm]]s, where many species of bacteria exist in close proximity to each other. This mixing of species allows ''E. coli'' strains that are piliated to accept and transfer [[plasmid]]s from and to other bacteria. Thus ''E. coli'' and the other [[enterobacteria]] are important reservoirs of transferable antibiotic resistance.<ref>{{cite journal |author=Salyers AA, Gupta A, Wang Y |title=Human intestinal bacteria as reservoirs for antibiotic resistance genes |journal=Trends Microbiol. |volume=12 |issue=9 |pages=412–6 |year=2004 |pmid=15337162 | doi = 10.1016/j.tim.2004.07.004 }}</ref>
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| === Beta-lactamase strains ===
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| Resistance to [[beta-lactam antibiotic]]s has become a particular problem in recent decades, as strains of bacteria that produce extended-spectrum [[beta-lactamase]]s have become more common.<ref>{{cite journal |author=Paterson DL, Bonomo RA |title=Extended-spectrum beta-lactamases: a clinical update |journal=Clin. Microbiol. Rev. |volume=18 |issue=4 |pages=657–86 |year=2005 |pmid=16223952 |url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=16223952 | doi = 10.1128/CMR.18.4.657-686.2005 }}</ref> These beta-lactamase enzymes make many, if not all, of the [[penicillin]]s and [[cephalosporin]]s ineffective as therapy. Extended-spectrum beta-lactamase–producing ''E. coli'' are highly resistant to an array of antibiotics and infections by these strains is difficult to treat. In many instances, only two oral antibiotics and a very limited group of intravenous antibiotics remain effective.
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| Increased concern about the prevalence of this form of "[[Antibiotic resistance|superbug]]" in the [[United Kingdom]] has led to calls for further monitoring and a UK-wide strategy to deal with infections and the deaths.<ref>{{cite web |title= HPA Press Statement: Infections caused by ESBL-producing E. coli |url= http://www.hpa.org.uk/hpa/news/articles/press_releases/2007/070924_esbl.htm}}</ref> Susceptibility testing should guide treatment in all infections in which the organism can be isolated for culture.
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| == Phage therapy ==
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| [[Phage therapy]]—viruses that specifically target pathogenic bacteria—has been developed over the last 80 years, primarily in the former [[Soviet Union]], where it was used to prevent diarrhea caused by ''E. coli''.<ref>{{cite web|url=http://www.iitd.pan.wroc.pl/phages/phages.html|title=Therapeutic use of bacteriophages in bacterial infections|publisher=Polish Academy of Sciences}}</ref> Presently, phage therapy for humans is available only at the Phage Therapy Center in the [[Republic of Georgia]] and in [[Poland]].<ref>{{cite web|url=http://www.phagetherapycenter.com/pii/PatientServlet?command=static_conditions&language=0|title=Medical conditions treated with phage therapy|publisher=Phage Therapy Center}}</ref> However, on January 2 2007, the United States FDA gave Omnilytics approval to apply its ''E. coli'' O157:H7 killing phage in a mist, spray or wash on live animals that will be slaughtered for human consumption.<ref>{{cite web|url=http://home.businesswire.com/portal/site/google/index.jsp?ndmViewId=news_view&newsId=20070102005459&newsLang=en|title= OmniLytics Announces USDA/FSIS Approval for Bacteriophage Treatment of ''E. coli'' O157:H7 on Livestock|publisher=OmniLytics}}</ref>
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| The [[Bacteriophage T4]] is a highly studied phage that targets E. coli for infection.
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| == Vaccination ==
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| Researchers have actively been working to develop safe, effective [[vaccine]]s to lower the worldwide incidence of ''E. coli'' infection.<ref name=Girard_2006>{{cite journal |author=Girard M, Steele D, Chaignat C, Kieny M |title=A review of vaccine research and development: human enteric infections |journal=Vaccine |volume=24 |issue=15 |pages=2732-50 |year=2006 |pmid=16483695 | doi = 10.1016/j.vaccine.2005.10.014 }}</ref> In March 2006, a vaccine eliciting an immune response against the ''E. coli'' O157:H7 O-specific polysaccharide conjugated to [[recombinant]] exotoxin A of ''[[Pseudomonas aeruginosa]]'' (O157-rEPA) was reported to be safe in children two to five years old. Previous work had already indicated that it was safe for adults.<ref name=Ahmed_2006>{{cite journal |author=Ahmed A, Li J, Shiloach Y, Robbins J, Szu S |title=Safety and immunogenicity of ''Escherichia coli'' O157 O-specific polysaccharide conjugate vaccine in 2-5-year-old children |journal=J Infect Dis |volume=193 |issue=4 |pages=515-21 |year=2006 |pmid=16425130 | doi = 10.1086/499821 }}</ref> A [[Phase III trials#Phase III|phase III clinical trial]] to verify the large-scale [[efficacy]] of the treatment is planned.<ref name=Ahmed_2006 />
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| In 2006 Fort Dodge Animal Health ([[Wyeth]]) introduced an effective live attenuated vaccine to control airsacculitis and peritonitis in chickens. The vaccine is a genetically modified avirulent vaccine that has demonstrated protection against O78 and untypeable strains.<ref name="Watt poultry.com_2008"> http://www.wattpoultry.com/PoultryInternational/Article.aspx?id=22434/</ref>
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| In January 2007 the Canadian bio-pharmaceutical company Bioniche announced it has developed a cattle vaccine which reduces the number of O157:H7 shed in manure by a factor of 1000, to about 1000 pathogenic bacteria per gram of manure.<ref name=Pearson_2007>{{cite journal |author=Pearson H |title=The dark side of E. coli |journal=Nature |volume=445 |issue=7123 |pages=8–9 |year=2007 |pmid=17203031 | doi = 10.1038/445008a <!-- Retrieved from CrossRef by DOI bot -->}}</ref><ref name=CanadaAM_2007>{{cite web | title=New cattle vaccine controls ''E. coli'' infections | work=Canada AM | url=http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20070111/ecoli_vaccine_cattle_070111/20070111?hub=CanadaAM | date=2007-01-11 | accessdate=2007-02-08}}</ref><ref name=BionichePR_2007>{{cite press release | title = Canadian Research Collaboration Produces World's First Food Safety Vaccine: Against ''E. coli'' O157:H7 | publisher = Bioniche Life Sciences Inc. | date = [[2007-01-10]] | url = http://www.cnxmarketlink.com/en/releases/archive/January2007/10/c4698.html | accessdate = 2007-02-08}}</ref>
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| == Role in biotechnology ==
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| Because of its long history of laboratory culture and ease of manipulation, ''E. coli'' also plays an important role in modern [[biological engineering]] and [[industrial microbiology]].<ref name="lee1996">{{cite journal |author=Lee SY |title=High cell-density culture of Escherichia coli |journal=Trends Biotechnol. |volume=14 |issue=3 |pages=98–105 |year=1996 |pmid=8867291 |doi=10.1016/0167-7799(96)80930-9}}</ref> The work of [[Stanley Norman Cohen]] and [[Herbert Boyer]] in ''E. coli'', using [[plasmid]]s and [[restriction enzyme]]s to create [[recombinant DNA]], became a foundation of biotechnology.<ref name="birth">[http://www.nature.com/nature/journal/v421/n6921/full/nj6921-456a.html "Special Report: The birth of biotechnology"], ''Nature'' 421, 456-457 (23 January 2003)</ref>
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| Considered a very versatile host for the production of [[heterologous]] [[protein]]s,<ref name="Cornelis"/> researchers can introduce genes into the microbes using plasmids, allowing for the mass production of proteins in [[industrial fermentation]] processes. Genetic systems have also been developed which allow the production of [[recombinant proteins]] using ''E. coli''. One of the first useful applications of [[recombinant DNA]] technology was the manipulation of ''E. coli'' to produce human [[insulin]].<ref>{{cite web |url=http://www.littletree.com.au/dna.htm |title=Recombinant DNA Technology in the Synthesis of Human Insulin |accessdate=2007-11-30 |last=Tof |first=Ilanit |coauthors= |year=1994 |work= |publisher=Little Tree Pty. Ltd.}}</ref> Modified ''E. coli'' have been used in [[vaccine]] development, [[bioremediation]], and production of immobilised [[enzyme]]s.<ref name="Cornelis">{{cite journal |author=Cornelis P |title=Expressing genes in different Escherichia coli compartments |journal=Curr. Opin. Biotechnol. |volume=11 |issue=5 |pages=450–4 |year=2000 |pmid=11024362 |doi=10.1016/S0958-1669(00)00131-2}}</ref> ''E. coli'' cannot, however, be used to produce some of the more large, complex proteins which contain multiple [[disulfide bond]]s and, in particular, unpaired [[thiol]]s, or proteins that also require [[post-translational modification]] for activity.<ref name="lee1996"/>
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| == Model organism ==
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| ''E. coli'' is frequently used as a [[model organism]] in [[microbiology]] studies. Cultivated strains (e.g. ''E. coli'' K12) are well-adapted to the laboratory environment, and, unlike [[wild type]] strains, have lost their ability to thrive in the intestine. Many lab strains lose their ability to form [[biofilm]]s.<ref>{{cite journal |author=Fux CA, Shirtliff M, Stoodley P, Costerton JW |title=Can laboratory reference strains mirror "real-world" pathogenesis? |journal=Trends Microbiol. |volume=13 |issue=2 |pages=58–63 |year=2005 |pmid=15680764 |doi=10.1016/j.tim.2004.11.001}}</ref><ref>{{cite journal |author=Vidal O, Longin R, Prigent-Combaret C, Dorel C, Hooreman M, Lejeune P |title=Isolation of an Escherichia coli K-12 mutant strain able to form biofilms on inert surfaces: involvement of a new ompR allele that increases curli expression |journal=J. Bacteriol. |volume=180 |issue=9 |pages=2442–9 |year=1998 |pmid=9573197 |doi=}}</ref> These features protect wild type strains from [[antibody|antibodies]] and other chemical attacks, but require a large expenditure of energy and material resources.
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| In 1946, [[Joshua Lederberg]] and [[Edward Tatum]] first described the phenomenon known as [[bacterial conjugation]] using ''E. coli'' as a model bacterium,<ref>{{cite journal |last=Lederberg |first=Joshua |coauthors=E.L. Tatum |year=1946 |month=October 19 |title=Gene recombination in E. coli |journal=Nature |volume=158 |issue= |pages=558 |id= |url=http://profiles.nlm.nih.gov/BB/G/A/S/Z/_/bbgasz.pdf |doi=10.1038/158558a0|format=PDF}} Source: [http://profiles.nlm.nih.gov/BB/G/A/S/Z/ National Library of Medicine - The Joshua Lederberg Papers]</ref> and it remains the primary model to study conjugation.{{Fact|date=December 2007}} ''E. coli'' was an integral part of the first experiments to understand [[bacteriophage|phage]] genetics,<ref>{{cite web |url=http://www.cshl.edu/History/phagecourse.html |title=The Phage Course - Origins |accessdate=2007-12-03 |last= |first= |coauthors= |year=2006 |work= |publisher=Cold Spring Harbor Laboratory}}</ref> and early researchers, such as [[Seymour Benzer]], used ''E. coli'' and phage T4 to understand the topography of gene structure.<ref>{{cite journal |last=Benzer |first=Seymour |coauthors= |year=1961 |month=March |title=On the topography of the genetic fine structure |journal=PNAS |volume=47 |issue=3 |pages=403–415 |id= |url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=221592 | doi = 10.1073/pnas.47.3.403 }}</ref> Prior to Benzer's research, it was not known whether the gene was a linear structure, or if it had a branching pattern.
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| [[E. coli long-term evolution experiment|Long-term evolution experiments using ''E. coli'']] have allowed direct observation of major evolutionary shifts in the laboratory.<ref>[http://www.newscientist.com/channel/life/dn14094-bacteria-make-major-evolutionary-shift-in-the-lab.html Bacteria make major evolutionary shift in the lab] ''New Scientist''</ref>
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| == See also ==
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| * [[E. coli long-term evolution experiment|''E. coli'' long-term evolution experiment]]
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| * [[T4 rII system|T4 ''rII'' system]]
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| * [[Bacteriological water analysis]]
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| * [[Coliform bacteria]]
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| * [[Contamination control]]
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| * [[Food poisoning]]
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| * E. coli gas production from glucose [http://www.tgw1916.net/movies2.html video demonstration]
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| == References ==
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| <!-- ---------------------------------------------------------------
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| See http://en.wikipedia.org/wiki/Wikipedia:Footnotes for a
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| discussion of different citation methods and how to generate
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| {{Reflist|2}}
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| == External links ==
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| {{wikispecies}}
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| {{commonscat|Escherichia coli}}
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| === General ===
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| * [http://redpoll.pharmacy.ualberta.ca/CCDB/cgi-bin/STAT_NEW.cgi ''E. coli'' statistics]
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| * [http://www.fda.gov/oc/opacom/hottopics/spinach.html Spinach and ''E. coli'' Outbreak - U.S. FDA]
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| * [http://www.cdc.gov/foodborne/ecolispinach/ ''E. coli'' Outbreak From Fresh Spinach - U.S. CDC]
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| * [http://www.micron.ac.uk/organisms/eco.html Current research on ''Escherichia coli'' at the Norwich Research Park]
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| === Databases ===
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| * [[EcoCyc]]: [http://www.ecocyc.org/ Encyclopedia of ''E. coli'' genes and metabolism]
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| * [http://www.ecosal.org/ EcoSal] Continually updated Web resource based on the classic ASM Press publication ''Escherichia coli and Salmonella: Cellular and Molecular Biology''
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| * [http://www.genome.wisc.edu/sequencing/upec.htm Uropathogenic Escherichia coli (UPEC)]
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| * [http://www.ericbrc.org NIAID Enteropathogen Resource Integration Center (ERIC)] Genome information on diarrheagenic ''E.coli'' and evolutionarily related organisms
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| * [http://www.ecolicommunity.org/ EcoliHub] - Comprehensive data resource for E. coli K-12 and its phage, plasmids, and mobile genetic elements.
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| * [http://www.ecolihub.org/ecoliwiki EcoliWiki] is the community annotation component of [http://www.ecolihub.org EcoliHub] whose goal is to provide an information resource on the model organism ''E. coli'' K-12, phages, plasmids, and mobile genetic elements.
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| * [http://www.casper.organ.su.se/ECODAB/ ECODAB] The structure of the O-antigens that form the basis of the serological classification of ''E. coli''
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| {{Model Organisms}}
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| [[Category:Enterobacteria]]
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| [[pl:Pałeczka okrężnicy]]
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| [[pt:Escherichia coli]]
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| [[ru:Бактерии группы кишечных палочек]]
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| [[simple:Escherichia coli]]
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| [[sk:Escherichia coli]]
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| [[sl:Escherichia coli]]
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| [[sr:Ешерихија коли]]
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| [[fi:Escherichia coli]]
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| [[sv:Escherichia coli]]
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| [[th:อีโคไล]]
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| [[vi:Escherichia coli]]
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| [[chr:Escherichia coli]]
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| [[tr:Escherichia coli]]
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| [[uk:Кишкова паличка]]
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| [[zh:大腸桿菌]]
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| | |
| {{WH}}
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| {{WS}}
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