Lecture 17 - Escherichia Coli Flashcards
1
Q
Enterobacteriacea: gram
A
negative
2
Q
Enterobacteriacea: morphology
A
rods
3
Q
Enterobacteriacea: catalase
A
positive
4
Q
Enterobacteriacea: oxidase
A
negative
5
Q
E. Coli: fermentation
A
Lactose
6
Q
E. Coli: hemolysis
A
Beta
7
Q
What is E. coli commonly responsible for? (very basic answer, think location)
A
Extraintestinal disease
8
Q
What is important to know about E. coli that causes enterocolitis?
A
NOT normal flora
9
Q
What are the four serotypes in e. coli?
A
O - H - K - F
10
Q
E. Coli: O antigen
A
Somatic - LPS
11
Q
E. Coli: H antigen
A
Flagellar - Protein
12
Q
E. Coli: K antigen
A
Capsular - polysacchrides
13
Q
E. Coli: F antigen
A
Fimbrial - Protein
14
Q
What is the major E. coli responsible for zoonosis?
A
E. Coli O157:H7
15
Q
What does E. coli O157: H7 cause?
A
Hemorrhagic colitis
Hemolytic uraemic syndrome
16
Q
What is the usual source of E. coli outbreaks?
A
Manure + Fecal material of infected cows
17
Q
What are the two groups of E. coli’s?
A
Enteric + Extraintestinal
18
Q
What are the enteric strains of E. coli?
A
ETEC
AEEC
EAggEC
19
Q
What does ETEC stand for?
A
Enterotoxigenic
20
Q
What does AEEC stand for?
A
Attaching and Effacing
21
Q
What does EAggEC stand for?
A
Enteroaggregative
22
Q
What are the types of AEEC?
A
EPEC + STEC
23
Q
What does EPEC stand for? What are the subtypes?
A
Enteropathogenic - Atypical and Typical
24
Q
What does STEC stand for? What are the subtypes?
A
Shiga-toxin producing - EHEC EnteroHEMOrrhagic
25
What are the extraintestinal strains of E. Coli?
APEC
SEPEC
UPEC
26
What does APEC stand for?
Avian Pathogenic
27
What does SEPEC stand for?
Septicemic pathogenic
28
What does UPEC stand for?
Uropathogenic
29
What are the four categories of virulence factors?
Capsular polysaccharides
Endotoxins
Fimbrial attachments
Secreted toxins
30
What types of toxins are secreted from E. coli?
Enterotoxin
Shigatoxin
Cytotoxic necrotizing factors
31
What is another name for shigatoxin?
Verotoxin
32
What is the function of the fimbrial attachments?
Attachment to mucosal + epithelium surfaces
33
What is another type of adhesion besides fimbrial?
Intimin + EAF + CS31A
34
What does the attachment of the bacteria cause in the host?
Actin pedestals form the actin rearrangement
35
What is LPS (endotoxin) made up of?
Lipid A - Polysaccharide + Side chains
36
What does LPS cause in the body?
Pyrogenic activity
Vascular coagulation
Shock
37
What does the capsule do in aidding in infection of E. Coli?
Makes the bacteria slippery
| Complement + Phagocytes can't bind
38
What E. Coli uses Cs31A adhesion?
SEPEC - sepecemtic pathogen
39
Where is the surface antigen for CS31A found?
Calves
40
What E. Coli uses EAF?
EPEC - Enteropathogenic
41
What E. Coli uses Fimbrial adhesions?
EAggEC - AA fimbriae
42
What E. coli uses Intimin?
AEEC - Attaching and effacing
43
How does intimin work?
Attaches to host cell and via T3SS will inject Tir proteins
Host cell will present Tir receptors
E. Coli attaches --> actin pedestal forms
44
What does the actin pedestal allow for?
Very strong adhesion by E. Coli
| Prevents washing off
45
What does the actin pedestal cause pathogenically in the animal?
Premature enterocyte exfoliation - diarrhea
46
What genetic feature do AEEC have?
Pathogenicity islands LEE
47
What are pathogencitiy island LEE required for?
needed for bacteria to be virulent
48
What does LEE stand for?
Locus of enterocyte effacement
49
What does LEE encode for?
Intimin + TiR + T3SS
50
What are the two categories of enterotoxins, besides cytotoxic necrotizing factors?
Heat-labile (LT) + Heat-stable (ST)
51
What types of E. coli enterotoxins are Heat-labile?
Shigatoxin + LT1 + LT2
52
What types of E. Coli enterotoxins are Heat-stable?
STa + STb + EAST1
53
What are the two E. Coli strains that have LT toxins?
STEC - Shiga toxin producing
| ETEC - Enterotoxigenic
54
What animals are affected by the LT toxins?
Pigs + Cattle
55
What LT toxin affects cattle? What E. coli strain?
LT2 - ETEC (enterotoxigenic)
56
What are the two toxins that affect pigs? What E. Coli strains?
STEC - Shiga-toxin
| ETEC - LT1
57
What does LT1 bind to in pigs?
K88 receptor
58
What does LT1 binding induce?
Hypersecretion of fluids
59
What does Shigatoxin cause in pigs?
Enterocytotoxic + Neurotoxic
| Hemorrhage + Edema + Thrombosis
60
What does shigatoxin do biochemically?
Binds to and inactivates ribosomes
| Stop protein synthesis --> cellular death
61
What point in a pigs life cycle are K88 receptors expressed the most?
Young
62
What E. coli strain contains STa?
ETEC - enterotoxigenic
63
What animals does the STa toxin infect?
Cattle + Pigs + Sheep
64
What does STa toxin cause?
Hypersecretion + Malabsorption of fluid
65
What does the STb toxin cause?
Hypersecretion + Malabsorption
66
What does EAST1 stand for?
Enteroaggregative heat stable toxin
67
What E. coli contains EAST1 toxin?
ETEC - enterotoxigenic
EPEC - Enteropathogenic
EHEC - Enterohemorrhagic
EAggEC - Enteroaggregative
68
What is important to note about EAST1 toxin?
ENHANCES hypersecretion + malabsorption
| Does not produce problems on its own
69
What two animals most commonly experience enteric colibacillosis?
Pigs + Calves
70
When do pigs come down with enteric colibacillosis? What are the symptoms?
Within 24 hours of birth
| Watery diarrhea + Dehydration + Weakness + Death
71
What is seen in calves with enteric colibacillosis?
Dehydration + Death + Diarrhea
72
What is a big sign that your calf has enteric colibacillosis?
Diarrhea is watery + pasty + white/yelllow + Rancid
73
What two E. coli are responsible for enteric colibacillosis?
AEEC + ETEC
74
What does AEEC cause in enteric colibacillosis?
Necrosis of enterocytes + loss of microvilli
75
What does ETEC bind to in enteric colibacillosis?
K88 + K99 fimbrial adhesins
76
What two toxins does ETEC secrete that cause enteric colibacilosis?
LT1 + STa
77
What is another term for diarrhea in pigs and cattle?
Scour
78
What animals do you see Colisepticemia?
Lambs + Calves + Poultry
79
What disease is seen in lambs with colisepticemia?
Watery mouth
80
What are the symptoms of Water mouth in lambs?
Profuse salivation + Distended abdomen
Endotoxic shock
High mortality
81
What does the severity of colisepticemia in calves correspond with?
Degree of hypo-Ig
82
What do you see in calves that have recovered from colisepticemia?
Post-septicemic localization to joints
83
What is seen in poultry with colisepticemia?
Airsacculitis
Pericarditis
Coligranuloma
84
What disease does Coligranuloma cause in poultry with colisepticemia?
Hjarre's disease
| Chronic inflammation
85
What animal do you see edema disease in?
Pigs
86
What causes the onset of edema disease?
Shigatoxin in the blood stream leading to perivascular edema
87
What is a sign that a pig is suffering from edema disease?
Eyelid swelling
| Hoarse squeal due to swelling of the larynx
88
When does edema disease in pigs tend to occur?
1 to 2 weeks post weaning
89
What happens within 36 hours of edema disease onset?
Paralysis - peracute death
90
What happens commonly when a pig survives edema disease?
CNS defects
91
What is seen in cattle that are affected with e. coli (females)?
Coliform mastitis
92
What do the milk secretions look like in cattle with e.coli infections?
Watery with white flakes
93
How long does coliform mastitis become fatal in cattle?
24 to 48 hours
94
What does a cattle with coliform mastitis look like physically?
Depressed
| Drooping ears + sunken eyes
95
What kind of urogenital infections does E. Coli cause?
UTI + Cystitis
Pyometra
Prostatitis
96
What animals experiences post-weaning diarrhea from E. coli?
Pigs
97
What e. coli strains are responsible for PWD?
ETEC - enterotoxigenic
| EPEC - enteropathogenic
98
What is big sign that a pig is suffering from PWD?
Diarrhea with purple discolored patches of skin
99
How do you know that the pig is suffering from PWD rather then Salmonella?
Purple patches all over rather then just ears
100
What specific assay is for E. Coli?
Vero cell assay
101
What specific characteristics does e. coli have?
```
Motile
Lactose fermentation
Imdole
Methyl-red
Lysine decarboxylase
```
102
What does E. Coli look like when it grows on MacConkey?
Red agar/colonies
| Lactose fermentor
103
What are the TSI results for E. Coli?
All yellow
No H2S production
GAS!
104
What is an important way to prevent E. Coli infections in cattle?
COLOSTRUM!
105
What animals have access to E. Coli vaccines?
Cattle + Pigs + Poultry
