general charactaristices
1-discoverd by Theodar Esherich
2-one members of enterobacteriacea
3-gram-negative rods
4-motile.the flagella of E coli charactarized byaperitricous arrangment.
5-non-sporing
6-fucultative anaerobic
7-optimal growth at37c
8-has the abilityto transfer DNA via bacterial conjugation,transduction,or transformation which allow genetic material to spread horiozantly through existing population
habites
e coli present mainly in intestinal tract2-one members of enterobacteriacea
3-gram-negative rods
4-motile.the flagella of E coli charactarized byaperitricous arrangment.
5-non-sporing
6-fucultative anaerobic
7-optimal growth at37c
8-has the abilityto transfer DNA via bacterial conjugation,transduction,or transformation which allow genetic material to spread horiozantly through existing population
habites
e coli have the ability to survive for brief period outside the body makes them an ideal indicator organisms to test enviromental samples for fecal
contamination
over 700serotypes of e.coli ,most of them are harmless
some such as serotype O157:H can cause food poisoning in human
#to distinushed serotypes from each other by O(somatic antigen)and H (flagella antigen)s
Types of toxins secreatedby e.coli
1-shiga toxin(STEC
2-verocytotoxin(VTEC
3-enterohymorrhagic toxin (EHEC
LABORATORY DIAGNOSIS
1-shiga toxin(STEC
2-verocytotoxin(VTEC
3-enterohymorrhagic toxin (EHEC
LABORATORY DIAGNOSIS
a-macCokey agar
on macConkey agar the colonies appear with deep red colonies
#e.coli is lactose positive,fermatation of lactose will cause the medium pH to drop leading to darking the medium
b-EMB
the colonies appear black with greenish-black metalic sheen
c- blood agar
biochemical reaction
imvic test
I= indole=positive=red ring
M=methyle blue=positive=bright red
V=voges preskauer=negative
C=citrate=negative
#e.coli ferment glucose maltose,sucrose,lactose produce acid and gas
e.coli lysin positive
pathogensis of e.coli
e.coli cause the followig disease
a-gastroenterites
b -urinary tract infection
c -neonatal meningititise
d -human uremic syndrom
on macConkey agar the colonies appear with deep red colonies
#e.coli is lactose positive,fermatation of lactose will cause the medium pH to drop leading to darking the medium
b-EMB
the colonies appear black with greenish-black metalic sheen
c- blood agar
biochemical reaction
imvic test
I= indole=positive=red ring
M=methyle blue=positive=bright red
V=voges preskauer=negative
C=citrate=negative
#e.coli ferment glucose maltose,sucrose,lactose produce acid and gas
e.coli lysin positive
pathogensis of e.coli
e.coli cause the followig disease
a-gastroenterites
b -urinary tract infection
c -neonatal meningititise
d -human uremic syndrom
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