Escherichia Coli

(E. coli)REGINE, ASHIYA, DENISE, SHAYLOR

What is E. coli?

E.coli (Escherichia coli) are a large and multiform group of bacteria that lives in the intestines of animals and people.

Most strains of E.coli are harmless, others can make you very sick. Some kinds of E. coli can cause diarrhea, while others cause respiratory illness, urinary tract infections, pneumonia, and other illnesses.

Signs & symptoms

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 sores in

the intestines.

Nausea

Vomiting

Fever

Fatigue - diarrhea causes loss of fluids and electrolytes (dehydration), making the

patient feel sick and tired

Morphology & Cell Type

E COLI IS A SINGLE CELLED PROKAROYOTIC ORGANISM.

E COLI IS GRAM-NEGATIVE.

IT IS A BACILLUS BACTERIUM SO IT IS ROD-SHAPED IN STRUCTURE.

E COLI LOOKS LIKE A LITTLE TUBE WITH HAIRLIKE PROJECTIONS AND A TAIL

ATTACHED (WHICH REPRESENTS A FLAGELLA).

E COLI POSSESSES ADHESIVE FIMBRIAE AND A CELL WALL THAT CONSISTS OF AN

OUTER MEMBRANE CONTAINING LIPOPOLYSACCHARIDES, A PERIPLASMIC SPACE

WITH PEPTIDOGLYCAN LAYER, AND AN INNER CYTOPLASMIC MEMBRANE.

EVEN THOUGH E COLI HAS AN EXTREMELY SIMPLE CELL STRUCTURE, WITH ONLY

ONE CHROMOSOMAL DNA AND A PLASMID, IT CAN PERFORM COMPLICATED

METABOLISM TO MAINTAIN ITS CELL GROW AND CELL DIVISION.

http://www.youtube.com/watch?v=Rlyfc-5fVqI

Virulence Factors

Virulence factors of Escherichia coli are of two main types; those

produced on the surface of the cell and those produced within the

cell and then exported to the site of action.

Those on the surface include different sorts of fimbriae that have a role in adhesion to the surface of host cells but may also have

additional roles such as tissue invasion, biofilm formation or cytokine

induction.

Other virulence factors enable the bacteria to grow in an environment of iron restriction.

Virulence Factors

Shiga toxin enters cells and stops the cells from producing proteins it needs

to function. Without the ability to sustain its function, the cell dies

P fimbriae are responsible for adhesion to mucosal and tissue matrix and

for the production of cytokines

S fimbriae may facilitate bacterial dissemination within host tissues and are

often associated with E. coli strains that cause sepsis, meningitis, and

ascending UTIs

Flagella an organelle responsible for bacterial motility, is involved in the

interaction of various pathogenic E. coli strains with epithelial cells.

More Virulence Factors

Virulence factors located on the bacterial surface include the capsule

and the lipopolysaccharide (LPS).

The capsule provides protection against phagocytic engulfment and complement-mediated bactericidal effect in the host. Certain capsular types,

for example, K1 and K5, show a molecular mimicry to tissue components,

preventing a proper humoral immune response of the infected host

The LPS is an integral component of the cell wall of Gram-negative bacteria. LPS

is known to activate host response and to induce nitric oxide and cytokine

production

Medications

1. E. Coli Meningitis:

• Antibiotics (third generation

Cephalosporin)

2. E. Coli Pneumonia

• Antibiotics (third generation

Cephalosporin’s or

Fluroquinolones)

3. E. Coli Cholecystitis/Cholancitis

• Antibiotics (third generation

Cephalosporin’s that cover E.

Coli and Klebsiella organisms)

4. E. Coli Intra-abdominal Abcess

• Antiobiotics must include

anaerobic coverage

*Campicillin, sulbactam or Cefoxitin

More medications

5. E. Coli Enteric Infection

• Antimicrobial (dexycycline,

trimethoprim/sulfame thoxazole,

fluroquinolones and rifaximan)

6. “Uncomplicated” E. Coli Cystitis

• Fluoroquinolon

• *TMP/SMZ *nitrofurantoin

7. Recurrent E. Coli Cystitis

• Prophylaxis with a fluroquinolone

TMP/SMZ Nitrofurantoin

8. Acute Uncomplicated E. Coli

• Pyelonephritis (in young Women)

• Fluroquinolone or TMP/SMZ for 14-days

9. E. Coli Perinephric Abscess or Prostatitis

• Treated at least 6 weeks of Antibiotics

10. E. Coli Sepsis

• Antibiotics

Vaccines

Pathogenic Escherichia coli strains are involved in a diverse

spectrum of diseases, including intestinal and extraintestinal

infections (urinary tract infections and sepsis). The absence of a

broadly protective vaccine against all these E. coli strains is a

major problem for modern society due to high costs to health

care systems

Harmful types of E. coli, such as 0157, put out highly destructive

toxins that poison healthy cells. The infection can kill elderly

people or the very young. Some patients who survive develop

kidney failure or brain damage. Urinary infections and diarrhea

frequently are caused by strains of E. coli.

Vaccines

There are currently two E. coli O157 vaccines on the market –Canada’s Econiche, which blocks the protein that allows E. coli to colonize in a cow’s gut, and America’s Epitopix SRP, which prevents the pathogen’s iron uptake. Both are under limited licensing in the U.S.

Studies have suggested that implementation of an E. coli vaccine could reduce human illnesses by as much as 83%, but because cattle are asymptomatic carriers for the zoonotic disease, ranchers bear the cost of the vaccine without seeing much direct benefit

QUIZ

What is the scientific name for E. Coli?

A.Escherichia coli

B. Eubacterium coli

C.Entophysalis coli

D.Enterococcus coli

A. Escherichia coli

What type of Bacterium is E. Coli?

A.Spiochete

B.Coccus

C.Bacillus

D.Spirillum

C. Bacillus

Which is NOT a virulence factor of e. coli?

A.Protein A

B.Shiga Toxin

C.Flagella

D.S Fimbriae

A. Protein A

What is usually the first signs of e. coli?

A.Fever

B. Vomiting

C.Severe abdominal pain

D.Diarrhea

C. Severe abdominal pain

Implementation of an E. coli vaccine could

reduce human illnesses by as much as ___?

A. 83%

B. 10%

C.5%

D. 1%

A. 83%

Sources

Bien, Justyna, Olga Sokolova, and Przemyslaw Bozko. "Role Of UropathogenicEscherichia Coli Virulence Factors In Development Of Urinary Tract Infection And Kidney Damage." International Journal Of Nephrology (2012): 1-15. Academic Search Complete. Web. 23 Feb. 2014.

Reshes, G., Vanounou, S., Fishov, I., & Feingold, M. (2008). Cell shape dynamics in escherichia coli. Biophysical Journal, 94(1), 251-64. Retrieved from http://search.proquest.com/docview/215689801?accountid=11033

Recer, Paul. "Decoding of E. Coli could Lead to Vaccines." Austin American Statesman: 0. Sep 05 1997. ProQuest. Web. 24 Feb. 2014

http://www.foodsafetynews.com/2013/09/e-coli-cattle-vaccination-could-prevent-83-percent-of-human-cases/#.UwwFFPldWSo

http://www.textbookofbacteriology.net/e.coli.html

The End.