Site Loader

Escherichia Coli Essay, Research Paper


Escherichia coli

Escherichia coli

Escherichia coli is an Enterobactericeae bacterium. This household name is derived from the fact that about all species in it, more or less, invariably inhabit the bowels of worlds and animate beings. Because of its widespread presence in the environment and its ability to advance disease in worlds, one of the most outstanding members of this household is the species Escherichia coli. This bacteria is so common that its name has come to depict all similar bacteriums as coliform or coli-like.

These enteric bacterias are Gram-negative, nonspore-forming heterosexual rods, aerophilic and facultative anaerobes, runing from 1 to 2 millimeters in diameter and are from 3 to 10 millimeters in length. All species ferment glucose, which allows for a testing method known as presumptive E. coli, and all microscopically, are identical. Most species are motile with nonionic flagellae. They have been classified by a system developed in portion by Edwards and Ewing, and Escherichia was named after a German scientist named Escherich. Enterobactericeae is subdivided into five folks, Escherichieae being one of them.

E. coli occurs in tremendous Numberss in normal fecal matters and is widely distributed in the enteric canal of animate beings and worlds. Normally, it does no injury. Assorted species of E. coli are of particular importance to medical and sanitation forces because certain serotypes cause enteric and urinary piece of land infections and are transmitted in H2O and milk. E. coli is really similar to Salmonella and Shigella bacteriums and can merely be distinguished during biochemical trials in a research lab.

E. coli is present in wellness people and animate beings, and really AIDSs in the digestive procedures. The bulk of E. coli in the enteric piece of land are non disease-causing to the host being, but if by opportunity the bacteriums enter the urinary piece of land or any other portion of the host, disease occurs. Methods of taint could include unequal hand-washing after utilizing the lavatory, imbibing contaminated H2O or milk, eating undercooked contaminated meat, unsterile medical processs, and perforation of the bowels due to accident or another injury. Normal disease symptoms include traveler s diarrhoea, purging, cramping, and desiccation.

Since E. coli is ever present in fecal matters, and since other species of the Escherichieae folk often accompany and closely resemble it, this folk is often referred to as the coliform group. The presence of any of them in H2O, milk, or nutrient in considerable Numberss strongly suggests pollution with sewerage and fecal matters. These bacteriums are easy cultured and recognized, normally staying alive in nutrient and H2O for long periods of clip. The coliform group is the index species in bacteriologic scrutinies of H2O, milk and nutrient as grounds of faecal pollution and possible infection.

Sewage pollution can present a assortment of other diseases, such as viruses, Protozoa, and other harmful bacteriums, but E. coli is most prevailing and easiest to place.

A new development in the history of coliform diseases came in 1982, when a strain of E. coli labeled as 0157: H7 was identified as a human pathogen. Bunchs of disease eruptions have occurred across the United States since so, the most celebrated of which was the Jack in the Box incident in 1993 in the province of Washington, ensuing in four deceases and 176 hospitalizations. The Centers for Disease Control have establ

ished that undercooked beef beefburgers were the cause of the eruption. Since that clip, many more bunchs have been reported.

Cattles are the lone mammals that carry the O157: H7 serotype. It is dispersed during the butchering processing, when the bowels are ruptured by accident, sloping the contents and E coli onto the meat. The CDC estimates that about 1 % of American cowss are contaminated.

Peoples most likely to hold a terrible reaction to these bacteriums are those who are really immature, really old, or have a compromised immune system because of another disease. Daycare centres, nursing places, and infirmaries have the potency for terrible eruptions, chiefly because of transmittal during diaper-changing with contaminated custodies, and hand-mouth transmittal in immature kids.

The organic structure temperature of a healthy homo is the ideal temperature for E. coli O157: H7. Once it is ingested, it rapidly begins to multiply and there is small to halt it and intervention is limited. The symptom that distinguishes E. coli O157: H7 from the less-toxic serotypes is the presence of bloody diarrhoea, caused by the eroding of the liner of the big bowel by the bacteriums s toxin. The consequence of this find is that meat processing workss have begun to utilize more comprehensive proving methods and healthful steps in the handling and processing of the carcases, and the nutrient constitutions are following the guidelines for minimum-temperature cookery and bar of cross-contamination by proper nutrient handling processs.

There are likely other strains of E. coli that have non yet been discovered. Scientists are developing new proving techniques to distinguish between the strains, and between other closely related bacteriums. The consequence of these finds is the increased safety of the American nutrient and H2O supplies.

Although there are many ways of undertaking coliform diseases, there are some simple steps to forestall infection:

1 ) Wash of custodies with anti-bacterial soap and hot H2O before eating

2 ) Cooking meats to above 68o C. [ 155o F ] or until pinkness is gone

3 ) Routine testing of H2O supplies

4 ) Immediate medical attention in the event of accident or internal hurt

5 ) Proper handling of natural nutrients to forestall cross-contamination

6 ) Proper storage of natural meats

By following these simple safeguards, one can dramatically diminish the opportunity of coliform infection. The immature, the aged and the immuno-compromised must be highly careful of taint of nutrient, H2O and milk with coliform bacteriums.


1. Brown, David. Tracing an Epidemic to a Cryptic Microbe, Washington Post National Weekly Edition. February 15-21, 1993. P. 38.

2. Libkin, L. DNA Repair Enzyme: A Structure Revealed, Science News. July 8, 1995. P. 36.

3. Meeker-Lowry, Susan. Challenging the Meat Monopoly, Z Magazine. March, 1995. P. 28-35.

4. Papinchak, Steve. Killer Bacteria E. coli O157: H7 is Old Villain, Las Vegas Review-Journal & A ; Sun. January 31, 1993. P. 1A+ .

5. Park, Hee-Won. Crystal Structure of DNA Photolyase From Escherichia coli, Science. June 30, 1995. P. 1866-1872.

6. Puzo, Daniel P. On the Hamburger Trail, Los Angeles Times. September 22, 1994. P. H1+ .

7. Tomlinson, Stewart. Families in Fear, Oregonian. January 31, 1993. P. A1+ .

Grade Received: A- High School: Awards Biology

Post Author: admin

Leave a Reply

Your email address will not be published. Required fields are marked *