Presentation on:

Detection of Escherichia Coli in waterPresented to:Dr. Kashif Aslam

Presented by:Mahreen FatimaM.sc Biotechnology

Detection of Escherichia Coli in water

What are Escherichia Coli?Introduction: E. coli O157:H7 was first recognized as a cause of illness

during an outbreak in 1982 traced to contaminated hamburgers. Since then, most infections are believed to have come from eating undercooked ground beef.

However, some have been waterborne. In 1999, people became sick after drinking contaminated water in Washington County, New York and swimming in contaminated water in Clark County, Washington.

Escherichia coli, also known as E. coli is a bacterium

that is commonly found in the gut of endotherms (warm blooded organisms).

Types of Escherichia ColiEnteropathogenic (EPEC)Entrotoxigenic (ETEC)Enteroinvasive (EIEC)Enterohemorrhagic (EHEC)Enteroaggregative (EAggEC)

Signs and symptoms of E. coli infection

The patient will typically experience symptoms within three to four days after being exposed to the bacteria, however, in some cases they may appear within a day or a week.

The individual may experience: Abdominal pain - typically, the first symptom is severe abdominal cramping that comes

on suddenly. Diarrhea - a few hours after the sudden abdominal pain, the patient typically has

watery diarrhea. A day later there may be bright red bloody stools, caused by pores in the intestines.

Nausea Vomiting - note that many patients who become ill may not vomit Fever - note that many infected people may not have a fever Fatigue - diarrhea causes loss of fluids and electrolytes (dehydration), making the

patient feel sick and tired.

Most strains of E. coli are harmless. However, one group, including 0157:H7, produces a potent toxin - Shiga toxin - that is harmful for the lining of the small intestine.

Method of detection. The beach samples were filtered with a 20

microm pore size filter in order to remove algae, plant debris and large particles. The prefiltered water was then passed through a 0.45 microm pore size filter for concentration. The deposited bacteria were resuspended and then mixed with superparamagnetic polystyrene beads (diameter of 0.6 microm) that were coated with E. coli antibodies.

After IMS, the quantification of the E. coli was done by ATP bioluminescence. The results obtained with IMS-ATP bioluminescence correlated well with the plate count method (Rsq = 0.93). The detection limit of the assay was about 20 CFU/100 mL.

Prevention Methods Drinks - pasteurized milk, apple juice or cider are safer

than unpasteurized. Wash vegetables - especially leafy green ones. Washing

thoroughly might not protect you completely, but it helps. Wash cutlery and crockery - make sure knives, forks,

plates and serving dishes are thoroughly washed with warm, soapy water.

Store foods separately - use separate cutting boards, do not store raw ground beef right next to other foods.

Hand hygiene - wash your hands thoroughly with warm water and soap after going to the toilet, before preparing foods, after preparing foods, and after touching animals. Wash your hands regularly.

E.Coli are friendly bacterai too E. coli bacteria may also be friendly bacteria , researchers

from Cornell University wrote in Nature Chemical Biology (March 25, 2012 issue). The bacterium can produce sugar-modified proteins (glycoproteins) which allow for the production of cheaper and faster pharmaceutical drugs.

The scientists developed a new way of producing human therapeutic glycoproteins by using E. coli as a platform.

Specially designed and genetically engineered proteins are commonly used as medications, because they bind to specific protein receptor sites, and can have therapeutic benefits, such as preventing cancer cells from multiplying.