ENTEROBACTERIACEAE - E. COLI Flashcards
Name this disease in poultry caused by E. coli: (includes pathogenesis + clinical signs + target host)
- Primarily respiratory tract-> bloodstream -> acute colisepticemia, fibropurulent serositis, coligranuloma (chronic disease characterized by granulomatous lesions in the wall of the intestinal tract, liver and lungs
Coligranuloma - Hjarre’s Disease
Both STa and STb are insoluble and no biological activity in suckling mice. True or False?
False, only STb
Name this disease in swine caused by E. coli: (includes pathogenesis + clinical signs + target host)
- After weaning
- Bowel edema
- Colonization -> release of edema disease (ED) toxin -> bloodstream -> small arteries -> mural edema, hyaline degeneration, permeable to fluid
- ED toxin vasotoxin -> hypertensive
Edema disease
Shiga-like toxin structurally resembles cytotoxin of ?
Shigella dysenteriae type 1 (Shiga)
Give the E. coli strain (that causes enteritis) with the given data:
- Colonize the intestine
- Produce Shiga-like toxins and destroy microvilli layers
AEEC - attaching and effacing E. coli
Shiga-like toxin contains A and B subunits. Between the two, which has toxin-binding function?
B subunits
Name this disease in poultry caused by E. coli: (includes pathogenesis + clinical signs + target host)
- Diarrhea due to urinary water loss and not (?) sequel of enteritis
Avian colibacillosis
What are the benefits of harmless strains of E.coli to the body?
- Produces vitamin K
- Prevent establishment of pathogenic bacteria within the intestine
What are the antigens present in the members of Family Enterobacteriaceae?
- K (capsular antigen) - capsular polyscaccharide particularly heavy in Klebsiella
- H (flagellar) antigen - flagellar proteins of motile genera and species
- O (somatic) antigen - O-specific polysaccharide chain of lipopolysaccharide.
- Vi - capsule of Salmonella
STb (enterotoxin) is found in enterotoxigenic E. coli from ____ _____.
weanling pigs
What are the end effects of Edema disease toxin?
1.Hypertension
2. Panarteritis
Enterotoxin of E. coli consisting 2 dissimilar polypeptide subunits A and B -> 5B and 1A subunit in each entire toxin molecule.
LT enterotoxin
Give the different non-lactose fermenters under Family Enterobacteriaceae.
*** ShHYPS
1. Shigella
2. Yersinia
3. Proteus
4. Salmonella
Give the E. coli strain (that causes enteritis) with the given data:
- Produce enterotoxins
- Uses fimbrial adhesins to bind to enterocytes in the small
intestines - Produces 2 proteinaceous enterotoxins:
a. LT – similar to cholera toxins
b. ST – cGMP accumulation in the target cells and subsequent secretion of fluids and electrolytes into intestinal lumen - Non-invasive, do not leave intestinal lumen
ETEC - enterotoxigenic E. coli
Give the E. coli strain (that causes enteritis) with the given data:
- Do not produce enterotoxins or Shiga-like toxins and cause
enteritis by other unknown mechanism - Use adhesins known as intimin to bind host intestinal cells
- Virulence factor similar to Shigella
- Adherence to intestinal mucosa causes rearrangement of actin
in host cell causing deformation - Moderately invasive and elicits an immune response
- Changes in intestinal cell ultrastructure due to attachment and effacement is likely to cause diarrhea
EPEC - enteropathogenic E. coli
What is the major route of E. coli?
Feco-oral route
Certain strains of E. coli such as _____ produce lethal toxins.
O157:H7
Some of members of Family Enterobacteriaceae ferments glucose with acid production. True or False?
False, all members
STa (enterotoxin) is found in enterotoxigenic E. coli from _____ _____.
baby piglets
What are the antigens of E. coli?
- O
- K
- H
- F
Edema disease toxins produce ____ and _____ in mice and toxic changes in _____ cells.
paralysis and death; Vero
Name the diseases induced by E. coli in rabbits.
- Cecitis
- Diarrhea
Family Enterobacteriaceae is oxidase _____, catalase ______.
negative; positive
Name this disease in cattle caused by E. coli: (includes pathogenesis + clinical signs + target host)
- White scours, during first week of life
- Severe diarrhea with feces full of gas bubbles
- Die in a few days due to dehydration and acidosis
Enteric disease
Discuss the mechanism of action of LT toxin of E. coli.
B subunits bind to gangliosides GM1 on mucoid cells on the
intestines -> subunit A activates adenylate cyclase by
NAD-dependent ADP ribosylation of its regulatory subunits ->
levels of intracellular cyclic AMP increase which causes a net
outflow of Na, Cl and water from cell
Give other 5 members of Family Enterobacteriaceae.
- Morganella morganii (form. Proteus morganii/Providencia)
- Providencia spp.
- Serratia spp.
- Erwinia
- Opportunistic Enterobacteriaceae
- Citrobacter
- Enterobacter
- Serratia
- Edwardsiella
Name the diseases induced by E. coli in horse.
- Abortion in mares
- Congenitally abnormal foals unable to suckle, die within 24 H
Edema disease toxin is insoluble at _____ pH but soluble at _____ pH.
acidic; alkaline
Edema disease toxin can inhibit protein synthesis in endothelial cells of blood vessels. True or False?
True
STa (enterotoxin) is soluble in _____ and has biological activity in suckling mice.
methanol
Proteinaceous protein/toxin produced by most enteropathogenic E, coli from enteritis in human infants.
Shiga-like toxin (SLT)
Name this disease in swine caused by E. coli: (includes pathogenesis + clinical signs + target host)
- Shortly after weaning
- Hemolytic E. coli
- Change of diet leads to massive colonization of anterior small
intestine - Persists for 2 to 3 days, pigs collapse and die after short period of
diarrhea - Net efflux of sodium, water, bicarbonate and chloride into bowel
lumen
Weanling enteritis
Name this disease in lambs caused by E. coli: (includes pathogenesis + clinical signs + target host)
- Can induce enteric diarrhea
- Can induce bacteremic diarrhea - sudden death
Colibacillosis
Family Enterobacteriaceae are gram (-) short rods. True or False?
True
Give the mode of action of STa.
Activates guanylate cyclase in intestinal mucosal cells ->
inhibition of Na and Cl absorption by brush border
E. coli is absent from intestines of ____ and ____.
fish and cold-blooded animals
Give the different lactose fermenters under Family Enterobacteriaceae.
*** CEEK
1. Citrobacter
2. Escherichia
3. Enterobacter
4. Klebsiella
All members of Family Enterobacteriaceae are aerobic. True or False?
True, they can also be facultatively anaerobic
Give the E. coli strain (that causes enteritis) with the given data:
- Invade intestinal epithelial cells and replicate intracellularly
- Able to proliferate more effectively in host
AIEC - adherent-invasive E. coli
What are the diagnostic methods for E. coli?
- Culture and isolation
- FAT
- ELISA
Name this disease in cattle caused by E. coli: (includes pathogenesis + clinical signs + target host)
- E. coli most important causative agent
(haha this is mastitis,,, insufficient ppt infos)
Mastitis
Name this disease in poultry caused by E. coli: (includes pathogenesis + clinical signs + target host)
- Other term for mushy chick disease
Omphalitis
E. coli is commonly found in the ____ ____ of warm-blood animals (endotherms).
lower intestines
Give the E. coli strain (that causes enteritis) with the given data:
- Most infamous member of pathotype is O157:H7
- Causes bloody diarrhea without fever
- Causes hemolytic-uremic syndrome and sudden kidney failure
- Uses bacterial fimbria for attachment, moderately invasive
- Possesses Shiga toxin that elicit intense inflammatory response
EHEC - enterohemorrhagic E. coli
Who discovered E. coli?
Theodore Escherich - German pediatrician and bacteriologist
** 1885
Family Enterobacteriaceae possess fimbriae or pili. True or False?
True
Give the E. coli strain (that causes enteritis) with the given data:
- Fimbriae aggregate tissue cells
- Binds to intestinal mucosa to cause watery diarrhea without
fever - Non-invasive, produces hemolysins and ST enterotoxins similar to
ETEC - Found only in humans
EAEC - enteroaggregative E. coli
This toxin is associated with destruction of gut epithelial cell microvilli –> effacing E. coli
Shiga-like toxin
STb has effect in cyclic GMP levels in intestinal mucosal cells. True or False?
False, no effect
Edema disease toxin is related to what toxin found in hemorrhagic colitis in humans?
Shiga-like toxin 2 (SLT2)
Give the E. coli strain (that causes enteritis) with the given data:
- Only in humans
- Invade enterocytes and deeper layers of mucosa of intestine
- Syndrome similar to shigellosis with profuse diarrhea and high
fever
EIEC - enteroinvasive E. coli
Name this disease in swine caused by E. coli: (includes pathogenesis + clinical signs + target host)
- Piglets 1 to 4 days
- Adhesion -> colonization -> toxin production
- Profuse, pale yellow, watery diarrhea -> fatal dehydration within
18 hours -> mortality as high as 90%
Neonatal enteritis
These are the first of the E. coli toxins to be demonstrated.
Edema disease toxins
Family Enterobacteriaceae are motile with _____ flagella except ______ and ______.
peritrichous; Shigella and Klebsiella
What are the enterotoxins produced by E. coli?
- Plasmid encoded heat labile LT enterotoxin
- Heat stable ST enterotoxin
- Edema disease toxins
- Shiga-like toxin (SLT)
Name the diseases induced by E. coli in dogs.
- Bacteremia - fading puppy syndrome
- Pyometra, UTI
- Enteritis
How can an animal be immunized against E. coli?
- Passive antibodies
- Fimbrial K88 ag
- Bacterins to pregnant sows
- LT/ST enterotoxins
