Bacillus .cereus
general charactarestices
a-)gram-positive bacilli
b-)spore-forming
c-)aerobic and fucultative anaerobic
d-) most of them motile
e-)rods shape
Habitate
B.Cereus is widely distributed in nature and soil.,and isolated from avariety of food
Diagnosis
B.CEREUS grow on blood agar and cause hemolysis of the blood but B.anthraxe non-hemolytic
this plate show the colonies of B.creus on agar plate
if you want to see spore of B.cereus make gram-stain and show
a-)gram-positive bacilli
b-)spore-forming
c-)aerobic and fucultative anaerobic
d-) most of them motile
e-)rods shape
Habitate
B.Cereus is widely distributed in nature and soil.,and isolated from avariety of food
Diagnosis
B.CEREUS grow on blood agar and cause hemolysis of the blood but B.anthraxe non-hemolytic
this plate show the colonies of B.creus on agar plate
if you want to see spore of B.cereus make gram-stain and show
Biochemical Reaction
a-) catalase positive
b-)Voges-Preskauaer positive
c-) DNase positive
d-) resistant to polymixin B antibiotices
Types of toxin produced by B.cereus
they are two types
A-) Emetic toxin(ETE
B-) Enterotoxin
three types of enterotoxin
a-)hemolytic enterotoxin (HBL
cause intestinal fluid secretion
b-) non-hemolytic enterotoxin (Nhe
responsible for diarrhea in B.cereus of food poisoning
c-) Entk
is a sigle component protein that has not been showen to be involved in food poisoning
pathogeniesis
disease caused by B.cereus
A-) Diarrhea syndrome
charactarized by
a-) abdominal pain
b-)watery diarrhea
c-) symptoms appeare within 8-16 hours after meal
d-) the diarrheagenic toxin has high molecular weight,and is heat labile that could be inactivated by hating for 5 minutes at 56C
B-)Emetic syndrome
charactarized by
a-) vomiting
b-)nausea
c-)symptoms appeares within 1-5 hours after meal
d-)emetic toxin has low molecular weight.and is very heat stable
a-) catalase positive
b-)Voges-Preskauaer positive
c-) DNase positive
d-) resistant to polymixin B antibiotices
Types of toxin produced by B.cereus
they are two types
A-) Emetic toxin(ETE
B-) Enterotoxin
three types of enterotoxin
a-)hemolytic enterotoxin (HBL
cause intestinal fluid secretion
b-) non-hemolytic enterotoxin (Nhe
responsible for diarrhea in B.cereus of food poisoning
c-) Entk
is a sigle component protein that has not been showen to be involved in food poisoning
pathogeniesis
disease caused by B.cereus
A-) Diarrhea syndrome
charactarized by
a-) abdominal pain
b-)watery diarrhea
c-) symptoms appeare within 8-16 hours after meal
d-) the diarrheagenic toxin has high molecular weight,and is heat labile that could be inactivated by hating for 5 minutes at 56C
B-)Emetic syndrome
charactarized by
a-) vomiting
b-)nausea
c-)symptoms appeares within 1-5 hours after meal
d-)emetic toxin has low molecular weight.and is very heat stable
تعليق