Escherichia coli 0157:H7
Encounter and history:
Escherichia coli are gram negative, rod shaped bacteria that are often used in laboratory studies and are usually harmless, residing in the human digestive tract as part of the normal flora. E. coli 0157:H7 is a pathogenic strain of E. coli that was first identified as a cause of disease in the United States in 1982, during an investigation into an outbreak of gastrointestinal illness. The organism is also called enterohemorrhagic E. coli (EHEC) because it causes abdominal pain with diarrhea that may contain blood. It lives in the intestines of healthy cattle and can contaminate meat during slaughter. It is believed that the widespread use of antibiotics by American farmers has
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coli 0157:H7 are acid tolerant and can easily pass through the stomach. The can also grow from 10-50C with an optimal temperature of 37C. Up to 10% of patients will develop hemolytic uremic syndrome, the most important complication from E. coli 0157:H7. This disease, charictarized by acute renal failure, almost exclusively affects children and the elderly and is fatal in as many as 5% of cases with intensive care. E.coli 0157:H7 is responsible for about 90% of HUS cases and is the leading cause of kidney failure in children. It is caused by the spread of the bacteria and the toxins throughout the bloodstream. Any organ may potentially be affected but certain renal cells are the most vulnerable.
Virulence Factors:
The genome of E. coli 0157:H7 was recently sequenced and contains 1,387 new genes absent in non pathogenic strains. Analysis of the genome suggests that there are a variety of potential virulence genes that have yet to be explored, including fimbrial and other adhesions, secretion systems, and toxins. Many of the virulence genes are similar to those associated with pathogenesis in Salmonella and Shigella. Most of them are found on pathogenicity islands from viral DNA that is transmitted to the bacteria through the activity of a lysogenic phage. The two most important toxins, Stx1 and Stx2 (for shiga-toxin) are found on such islands and are composed of 5 B subunits surounding an active A component, which is transported into the cell after the
Escherichia coli, or better known as E. Coli, is one of the most commonly studied single-cell organisms because it is easier to manipulate and it is abundant. Some E. Coli strains can be pathogenic, but most are harmless. They can help benefit digestive health by filling niches in place of more harmful microorganisms. Because it is a diverse group of related microorganisms, it can be difficult to find the boundaries defining the species. Some strains are natural while others are genetically created in labs, which can be observed in aspects of an organism (Schussler).
Esherichia coli also known as E. coli is a bacterium that lives in your gut. (1). it was founded by Theodore von Esherich in 1888. There are many people that can get the bacteria. Also there are thousands of strands of E.coli. Six E. coli O157 outbreaks were identified during 2007. Four of the outbreaks involved foodborne transmission. (Eshericha Coli). Six Minnesota cases and one Wisconsin case with the same or closely-related PFGE subtype of E. coli O157:H7, and an additional Minnesota case of Shiga-toxin producing E. coli that was not culture-confirmed, attended the Minnesota State Fair in August. All but one of the cases showed cattle or visited the cattle
Escherichia coli are rod shaped, gram negative bacteria often found in the gut of humans and other warm-blooded mammals (Jacques & Ngo, 2004). It is transmitted primarily through faecal contaminated food and water. Most strains of E. coli are not harmful to humans, however some strains are pathogenic and can cause symptoms including diarrhoea (Unknown, 2012).
E. coli is a single chromosome (haploid). E. coli has 4600 kilobases with about 4300 coding sequences and has around 1800 known E. coli proteins. 70% of its genes are monocistronic and 6% are polycistronic, roughly having the same amount of genes on each strand [2]. E. coli is a member of normal flora that inhabits humans and other animals. E. coli is heterotrophic and usually obtains its food from the organism it is living in. E. coli is dependent on carbon; its main source of carbon is obtained from glucose. E. coli is a facultative anaerobe meaning that it can use oxygen and other electron acceptors as the final acceptor in an anabolic or catabolic pathway. The optimum temperature of E. coli is 37o C,
E. coli O157 infection can lead to hemolytic uremic syndrome (HUS), characterized by hemolytic anemia, thrombocytopenia, and renal injury. Still, it was not until 1993, after a large multistate E. coli
Escherichia Coli, located in one of the main organs known as the large intestine, is a type of bacteria that helps digestion. (Trzepacz, Timmons, and Duobinis-Gray, 2016) For Escherichia Coli to remain stable and alive, it needs specific necessities. These needs are known as the following: Energy, vitamins, and similar compounds. Escherichia Coli is found everywhere!
The orgimsms involved in Escherichia coli 0157 is an anaerobic bacterium which is shaped like a rod and is Gram-negative. Escherichia is a foodborne pathogen which causes a variety of disease in humans worldwide. Cattle are the reservoir to the diseases. Between 1% and 50% of healthy cattle carry or shed E.coli by means of their faeces. The cattle can also contract the infection after slaughter as conmtanation can occur during slaughter or while the beef is being proceed into products suitable for human consumption. In the United states the most common way of transmission of the disease is through consuming contaminated food and water. Although it is also frequently spread from person to person impartial in communities where there is a high concentration of children such as child care services and primary schools.
Escherichia coli (E. coli) is a bacteria usually found in warm blooded organisms such as human and animal intestines. Although there are large groups of E.coli, most strains are harmless. Other strains of the bacteria may cause diarrhea, respiratory illnesses and food poisoning. Some strains such as O157:H7 can cause kidney failure or severe anemia. Exposure to E.coli can be in the form of food, water, undercooked meat and even raw vegetables. Symptoms may include: nausea and vomiting, severe stomach cramps and stomach tenderness, diarrhea containing blood.
coli bacteria is a type of bacteria that can live in the intestines of animals and humans. However, there are some types of the E. coli bacteria, particularly E. coli 0157:H7, that can cause intestinal infections. Symptoms of this type of infection include dehydration, abdominal cramps, fever and bloody diarrhoea. These symptoms can endure 2-8 days after exposure to the bacteria. Since these symptoms generally resolve after a few days to a week, most cases of E. coli 0157:H7 infection can be treated at home.
Furthermore, dangerous strains of E. coli, such as E. coli O157:H7, produces toxins such as Shiga toxins. These toxins have the capabilities to damage the lining of the small intestine, which can result in stomach cramps, diarrhea, vomiting, nausea and bloody stool. If a person can come into contact with a contaminated source, symptoms can appear about three to four days after exposure and can usually last between one to nine days. The infected host is considered contagious until their symptoms stop and even a couple days after that. The way E. coli O157:H7 is diagnosed is by a special stool culture that is sent to a stool laboratory, where tests are run to
Escherichia coli (E.coli) has been a public health issue since the 1980s and is a major concern in food contamination in products like beef, dairy, and fresh produce. E.coli 0157:H7 itself is not invasive but it produces a Shiga toxin which attacks the host small blood vessels in the kidney. This makes the kidneys work harder which can destroy red blood cells and lead to hemolytic anemia (lowered number of red blood cells produced). The incubation period for E. coli ranges from three to eight days. The infection often causes severe bloody diarrhea and abdominal cramps, but can also cause non-bloody diarrhea or no symptoms. E.coli may greatly affects children and the elderly.
Every year over 96,000 people contract E.Coli, 3,200 of those people are hospitalized for E.Coli, and over 31 people die each year from E.Coli (Food News). E.Coli (otherwise known as Escherichia coli O157:H7) is a disease that is spread in many ways, the most common way being raw and uncooked food in the restaurant being served to the customer. Another way E.Coli is spread is through contact human/animal feces. E.Coli can be prevented, here are some ways to do so; Cook all meats to at least 160 degrees fahrenheit, wash your hands with warm water and soap (especially after touching raw meats), wash off all kitchen supplies thoroughly, use only pasteurized dairy and juice products, use/drink treated water, If you travel to another country that may have unsafe water don’t use tap or ice water, avoid raw fruits and veggies (Web MD).
Most e coli do not affect people and actually are a very important part of keeping people healthy especially in the intestinal tract. Although there are some e coli that are pathogenic this means that they cause illness this is done either by giving people diarrhoea or illness that is outside the intestinal tract. These types of e coli that cause diarrhoea are usually transmitted through contaminated water ,food, or contact with animals or persons. E coli kill people by causing dehydration from diarrhoea and vomiting. E coli are considered gram negative bacteria. Colonies of e coli are circular in shape as well as having an entire margin it is also raised and size is considered punctiform (small). The texture of the colony is also smooth and the appearance is shiny and is no pigmented (colourless) as well as being
If the immune system is unable to stop the infection, the bacterium will multiply and then spread to the bloodstream, after which the first signs of disease are observed in the form of fever. The bacterium penetrates further into the bone marrow, liver, and bile ducts, from which bacteria are excreted into the bowel movements. (Easmon 2003)
Escherichia coli are commonly found in lower intestine of warm blooded animals. Most E. coli are harmless. The bacteria can be grown easily and its genetics are relatively simple and easy to study, making it the best-studied prokaryotic organism. Certain strains of E. coli can produce toxins that can cause food poisoning when eating unwashed vegetables. (Wikipedia, 2010)