Enterotoxigenic Echichia Battery
Echerichia coli is a gram-negative bacterium that has a bacillus shape and belongs to the Enterobacteriaceae family, it is a normal flora microorganism, however there are strains that can be pathogenic and cause damage.(Guadalupe Rodríguez-Angels, 2002).
The e. coli was initially considered a component of the intestinal flora and not as a pathogen. In 1940 he was associated with diarrhea outbreaks in different parts of the world. These strains were classified as enteropathogenic, however the virulence mechanisms involved were unknown until 1967. It was this year where Smith and Halls reported the existence of Enterotoxigenic strains of E. coli in animals with diarrhea. Smith and Gyles then demonstrated that these bacteria produced two different types of enterotoxins: a thermostable, non -antigenic, low molecular weight and another thermolabil, immunogenic and high molecular weight. Finally the scientists Gorbach, Banwell, Chatterjee, Jacobs and Sack isolated the strains of E. Non -entropatogenic coli, these had the ability to colonize the small intestine of children with diarrhea, they also postulated that these strains should produce enterotoxins. (Liliana Reyes, 1978)
The e. Coli plays a positive function for the body, since it prevents the growth of harmful bacterial species and synthesizes a large number of vitamins. (Guadalupe Rodríguez-Angels, 2002). However, some strains of E. coli cause diseases in humans, through different mechanisms.
There are currently two pathogenic groups of E. coli that depend on the type of infection they cause in man. The first group consists of the strains of E. coli causing extraintestinal infections and the second group consists of intestinal pathogenic strains, responsible for most gastrointestinal infections. (Alvarez, 2020). Within the second group there are six types of E. coli:
- Escherichia Enterotoxigenic coli (ETEC).
- Enteroinvasive Escherichia (EIEC).
- Enterogregative Escherichia (EAEC).
- Enteropathogenic Escherichia (EPEC).
- Escherichia Coli Enterohemorrágicas (EHEC).
- Escherichia coli diffuse adhesion (DAEC).
The main pathogenicity mechanism of the Enterotoxygenic Echoichia (ETEC) strain is the synthesis of some or both enterotoxins called thermolabil toxin (LT) and thermostable toxin (ST), which can manifest together or only one of them, and causeDamage to epithelial cells.
ETEC is found in the stool of an infected person or animal and is the main cause of diarrhea. Water and food pollution is the main source of infection, after ingestion the microorganism is colonized and adheres to the enterocytes of the small intestine and multiplies, causing multiple damage. (Guadalupe Rodríguez-Angels, 2002)
The ETEC is anchored in the enterocytes through colonization factors (CFS) and an adhesine (ETPA) that is at the end of the scourge, thus giving colonization in the small intestine . Strong adhesion is measured by Aunt and Tiba. Thermolabil (LT) toxin and thermostable toxin (ST) are secreted. The LT and ST are regulated at the transcriptional level by a cyclic AMP -dependent protein (AMPC), this represses the expression of the LT while activating the expression of the ST. The ST, when secretized, joins Guanilaato Ciclasa C. This protein is expressed mainly in the cells of the intestinal epithelium. When the ST joins this receiver, it alters this route and causes diarrhea. It is important to keep in mind that this goes through the activation of the Transmembrane Cystic Fibrosis (CFTR) conductive regulator through the production of the second GMP cyclic messengers (GMPC) and Cyclic AMP. (Marx Peña Hidalgo, 2014)
Aqueous diarrhea begins in the period of 14 to 50 hours after the ingestion of the bacteria. Other symptoms such as: abdominal cramps, fever, nausea and muscle aches can also occur. No bleeding or mucus is presented.
As previously said, the largest source of contamination of ETEC are the consumption of contaminated food, contaminated water and cross pollution through direct human contact.
Many foods can be contaminated by ETEC during growth and cultivation, collection or slaughter. However, additional pollution can occur during postharvest, transport, elaboration and non -hygienic food manipulation during their preparation.
Some examples of contaminated foods are: raw/poorly elaborate meat, non -pasteurized dairy products, non -pasteurized fruit juices and raw vegetables.
Food products of animal origin
Fresh meat and raw milk are considered as common sources of ETEC, meat pollution usually occurs during animal slaughter, as a result of poor manipulation practices and bad general health conditions of slaughterhouses. In the case of raw milk, its contamination is due to environmental sources or directly by udder infection.
Fresh products and germinated seeds
Fresh products and germinated seeds are contaminated by the feces released from animals and humans that enter agroecosystems through manure, irrigation water, contaminated seeds and insect pests.
Processed foods
Processed foods can be contaminated through raw materials, inadequate manipulation of water and cross contamination. Therefore, it is necessary to control the parameters of the processes, such as pH value, water activity, temperature and time, to prevent bacteria from continuing to grow in food.
To avoid food pollution, it is necessary.
Bibliography
- Alvarez, b. R. (October 5, 2020). Characterization of Escherichia Coli strains of human clinical importance isolated from Sweet Ecosystems of Havana . Characterization of Escherichia Coli strains of human clinical importance isolated from Sweet Ecosystems of Havana . Havana, Cuba: University of Havana.
- Food and Agriculture Organization of the United Nations . (October 5, 2020). Food and Agriculture Organization of the United Nations . Obtained from Food and Agriculture Organization of the United Nations: http: // www.FAO.org
- Guadalupe Rodríguez-Angels, M. (2002). Main characteristics and diagnosis of the pathogenic groups of Escherichia coli. Public Health of Mexico, 464-475.
- Healthy People in a Healthy Southern Nevada. (October 5, 2020). Healthy People in a Healthy Southern Nevada. Obtained from Healthy People in a Healthy Southern Nevada: https: // www.Southern Nevada Health District.org/
- Liliana Reyes, D. J. (1978). Escherichia Enterotoxigenica coli in hospitalized children in Costa Rica. Medical Magazine National Children’s Hospital, 23-32.
- Marx Peña Hidalgo, C. D. (2014). Molecular identification of Enterotoxigenic Escherichia in children with acute diarrheal infections through the polymerase chain reaction. Amazon Science, 117-122.
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