Escherichia
Encyclopedia
Escherichia is a genus
of Gram-negative
, non-spore
forming, facultatively anaerobic
, rod-shaped bacteria
from the family Enterobacteriaceae
. In those species which are inhabitants of the gastrointestinal tract
s of warm-blooded
animals, Escherichia species provide a portion of the microbially-derived vitamin K
for their host. A number of the species of Escherichia are pathogenic. The genus is named after Theodor Escherich
, discoverer of E. coli
s, and are known as the most common cause of urinary tract infection
s, significant sources of gastrointestinal disease, ranging from simple diarrhea
to dysentery
-like conditions, as well as a wide-range of other pathogenic states. While Escherichia coli
is responsible for the vast majority of Escherichia-related pathogenesis, other members of the genus have also been implicated in human disease.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of Gram-negative
Gram-negative
Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol. In a Gram stain test, a counterstain is added after the crystal violet, coloring all Gram-negative bacteria with a red or pink color...
, non-spore
Endospore
An endospore is a dormant, tough, and temporarily non-reproductive structure produced by certain bacteria from the Firmicute phylum. The name "endospore" is suggestive of a spore or seed-like form , but it is not a true spore . It is a stripped-down, dormant form to which the bacterium can reduce...
forming, facultatively anaerobic
Facultative anaerobic organism
A facultative anaerobic organism is an organism, usually a bacterium, that makes ATP by aerobic respiration if oxygen is present but is also capable of switching to fermentation...
, rod-shaped bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
from the family Enterobacteriaceae
Enterobacteriaceae
The Enterobacteriaceae is a large family of bacteria that includes many of the more familiar pathogens, such as Salmonella, Escherichia coli, Yersinia pestis, Klebsiella and Shigella. This family is the only representative in the order Enterobacteriales of the class Gammaproteobacteria in the...
. In those species which are inhabitants of the gastrointestinal tract
Gastrointestinal tract
The human gastrointestinal tract refers to the stomach and intestine, and sometimes to all the structures from the mouth to the anus. ....
s of warm-blooded
Warm-blooded
The term warm-blooded is a colloquial term to describe animal species which have a relatively higher blood temperature, and maintain thermal homeostasis primarily through internal metabolic processes...
animals, Escherichia species provide a portion of the microbially-derived vitamin K
Vitamin K
Vitamin K is a group of structurally similar, fat soluble vitamins that are needed for the posttranslational modification of certain proteins required for blood coagulation and in metabolic pathways in bone and other tissue. They are 2-methyl-1,4-naphthoquinone derivatives...
for their host. A number of the species of Escherichia are pathogenic. The genus is named after Theodor Escherich
Theodor Escherich
Theodor Escherich was a German-Austrian pediatrician and a professor at universities in Graz, and Vienna...
, discoverer of E. coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
Pathogenesis
While many Escherichia are harmless commensals, particular strains of some species are human pathogenPathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
s, and are known as the most common cause of urinary tract infection
Urinary tract infection
A urinary tract infection is a bacterial infection that affects any part of the urinary tract. Symptoms include frequent feeling and/or need to urinate, pain during urination, and cloudy urine. The main causal agent is Escherichia coli...
s, significant sources of gastrointestinal disease, ranging from simple diarrhea
Diarrhea
Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...
to dysentery
Dysentery
Dysentery is an inflammatory disorder of the intestine, especially of the colon, that results in severe diarrhea containing mucus and/or blood in the faeces with fever and abdominal pain. If left untreated, dysentery can be fatal.There are differences between dysentery and normal bloody diarrhoea...
-like conditions, as well as a wide-range of other pathogenic states. While Escherichia coli
Escherichia coli
Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...
is responsible for the vast majority of Escherichia-related pathogenesis, other members of the genus have also been implicated in human disease.
See also
- E. coli O157:H7Escherichia coli O157:H7Escherichia coli O157:H7 is an enterohemorrhagic strain of the bacterium Escherichia coli and a cause of foodborne illness. Infection often leads to hemorrhagic diarrhea, and occasionally to kidney failure, especially in young children and elderly persons...
- List of bacterial genera named after personal names
External links
- Escherichia genomes and related information at PATRIC, a Bioinformatics Resource Center funded by NIAID