Escherichia

A genus of aerobic, facultatively anaerobic bacteria containing short, motile or nonmotile, Gram-negative rods. Motile cells are peritrichous. Glucose and lactose are fermented with the production of acid and gas. These organisms are found in feces; some are pathogenic to humans, causing enteritis, peritonitis, cystitis, etc. It is the type genus of the family Enterobacteriaceae. The type species is E. coli. [T. Escherich, German pediatrician and bacteriologist, 1857–1911]

- E. coli a species that occurs normally in the intestines of humans and other vertebrates, is widely distributed in nature, and is a frequent cause of infections of the urogenital tract and of neonatal meningitis and diarrhea in infants; enteropathogenic strains (serovars) of E. coli cause diarrhea due to enterotoxin, the production of which seems to be associated with a transferable episome; the type species of the genus. SYN: colibacillus, colon bacillus.

- enterohemorrhagic E. coli (EHEC) enterohemorrhagic strains of E. coli, commonly of the serotype 0157:H7; produces a toxin resembling that produced by Shigella; associated with damage to the epithelium, ischemia of the bowel, and necrosis of the colon. Apparently responsible for a hemorrhagic form of colitis without fever, which can be very severe; spread primarily by contaminated beef and poultry. May also cause microangiopathic hemolytic anemia, renal failure, and the hemolytic uremic syndrome.

- enteroinvasive E. coli (EIEC) enteroinvasive strain of E. coli penetrates gut mucosa and multiplies in colon epithelial cells, resulting in shigellosislike changes of the mucosa. This strain produces a severe diarrheal illness that can resemble shigellosis except for the absence of vomiting and shorter duration of illness.

- enteropathogenic E. coli (EPEC) enteropathogenic strain of E. coli; organisms adhere to small bowel mucosa and produce characteristic changes in the microvilli. This strain produces symptomatic, sometimes serious, gastrointestinal illnesses, especially severe in neonates and young children; typically it produces toxins, one of which is heat-labile, resembling that produced by Vibrio cholerae, the other heat-stable.

- enterotoxigenic E. coli (ETEC) enterotoxigenic strain of E. coli; attaches to the duodenum or proximal small intestine mucosa, where it forms heat-stable and heat-labile toxins that activate adenylate cyclase, causing watery diarrhea. Responsible for 40–70% of traveler's diarrhea; chiefly waterborne via human feces. Most important cause of diarrhea among infants living in tropical areas.

- E. freundii former name for Citrobacter freundii.

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Esch·e·rich·ia .esh-ə-'rik-ē-ə n a genus of aerobic gram-negative rod-shaped bacteria of the family Enterobacteriaceae that form acid and gas on many carbohydrates (as dextrose and lactose) but no acetoin and that include occas. pathogenic forms (as some strains of E. coli) normally present in the human intestine and other forms which typically occur in soil and water

Esch·e·rich 'esh-ə-rik Theodor (1857-1911)

German pediatrician. A seminal figure in pediatrics, Escherich used his extensive knowledge of bacteriology, immunology, and biochemistry to greatly advance child care, especially in the areas of hygiene and nutrition. In 1886 he published a monograph in which he discussed the relationship of intestinal bacteria to the physiology of digestion in infants. Therein he gave the first description of a colon bacillus (Escherichia coli) now extensively used in genetic research.

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n.

a genus of Gram-negative, generally motile, rodlike bacteria that have the ability to ferment carbohydrates, usually with production of gas, and are found in the intestines of humans and many animals. E. coli - a lactose-fermenting species - is usually not harmful but some strains cause gastrointestinal infections. Ingestion of the pathogenic serotype E. coli O157, derived from infected meat, causes colitis with bloody diarrhoea, which may give rise to the complications of haemolytic uraemic syndrome or thrombocytopenic purpura (see also food poisoning). E. coli is widely used in laboratory experiments for bacteriological and genetic studies.

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Esch·e·rich·ia (esh″ə-rikґe-ə) [T. Escherich] a genus of gram-negative, facultatively anaerobic, rod-shaped bacteria of the family Enterobacteriaceae, found in the large intestines of many mammals and birds. Most species are nonpathogenic or opportunistic pathogens. This genus is a member of the “coliform” group of bacteria, their presence in water supplies being used as an indicator of fecal contamination. The type species is E. cloaґcae.