Escherichia coli Flashcards
gram
shape
respiration
motility?
ferment glucose?
ferment lactose?
oxidase
catalase
gram negative
rod
facultative anaerobe
motile by peritrichous flagella
ferment glucose
ferment lactose
oxidase negative
catalase positive
where do they normally live, are most pathogenic
normally live in intestinal tract
most are avirulent
how can they cause disease
when acquire virulence
escape gut
antimicrobial resistane casues what and is due to what
causes treatment failure
due to beta lactams, fluorquinolones
what is LPS lipid A
active component of endotoxin
which ones are in small bowel
ETEC
EPEC
which ones are in large bowel
EHEC
EIEC
what is ETEC, where is it located
enterotoxigenic e coli
small bowel
ETEC fimbrial adhesins
attachment to small intestine
ETEC enterotoxins
heat labile enterotoxin (LT) – cAMP
heat stable enterotoxin (ST) – cGMP accumulation in cells
what type of diarrhea does ETEC cauase
watery diarrhea
ETEC – neonatal diarrhea – animals affected
enteric colibacillosis
newborn calves, lambs, piglets (first week of life)
ETEC – neonatal diarrhea – how do animals become resistant
shed fibroreceptors as age – become resistant to ETEC
ETEC – neonatal diarrhea – syptoms
diarrhea, dehydration, death
ETEC – neonatal diarrhea – treatment
milk with fluids and electrolytes
hydration
ETEC – neonatal diarrhea – control
feed ample colostrum
ETEC – postweaning diarrhea – animals affected
enteric colibacillosis
common cause of death in weaned pigs (1-2 weeks post weaning)
ETEC – postweaning diarrhea – what can case it
ETEC or EPEC
ETEC – postweaning diarrhea – symptoms
watery diarrhea, loss of appetite, purplish discoloration of skin
ETEC – postweaning diarrhea – control
vaccination, breeding for disease ressitance
ETEC – postweaning diarrhea – treatment
antimicrobial resistance testing important
what is EPEC and where is it located
enteropathogenic e coli
small bowel
EPEC – adhesion
no fimbrio adhesion
intimin
EPEC – lesions
pedestal formation – loss of microvilli
attaching and effacing lesions
EPEC – symptoms
watery diarrhea
contributes to post weaning diarrhea
what is EHEC and where is it located
enterohemorrhagic e coli
large bowel
virulence of EHEC
intimin
T3SS
attaching and effacing lesions
EHEC key virulence factor
shiga toxin – hemorrhagic diarrhea, kidney failure
other names for EHEC
shiga toxin producing e coli (STEC)
verocytotoxin producing e coli (VTEC)
primary reservoir of EHEC, do they get sick
cattle
cattle remain healthy
why do cattle remain healthy with EHEC
cattle don’t have shiga toxin receptor Gb3
EHEC – edema disease of pigs – age of pigs, what type of shiga toxin
1-2 weeks after weaning
shiga toxin strain stx2e
EHEC – edema disease of pigs – symptoms
swelling of eyelids, muscular tremors, unusual squeal or snort, neurological dysfunction, flaccid paralysis and death within 36 hours
what is EIEC and location
enteroinvasive e coli
large bowel
what type of pathogen is EIEC
obligate intracellular pathogen in colon
EIEC virulence
ipaH
T3SS
EIEC symptoms
inflammation, necrosis, ucleration of bowel
watery to bloody diarrhea with fever
which speceis relatively resistnat to EIEC
dogs and cats relatively resistant
human enteric pathogen
shigella:
gram
shape
motility?
toxin
symptoms
disease
hosts
gram negative
rod
non motile, no flagella
produces shiga toxin
bloody diarrhea
shigellosis
more of a human pathogen
can invade host cell
what is ExPEC, different types
extraintestinal pathigenic e coli
SEPEC
APEC
UPEC
MPEC
what is SEPEC
animals affected
what does it invade
septicemia e coli
newborn calves, lambs, poultry, immunocompromised animals
invasion of bloodstream – systemic infection
SEPEC – virulence
fimbrial ahdesions
serum resistance
aerobactin iron uptake
LPS
cytotoxic necrotizing factors
SEPEC in lambs
watery mouth disease in lambs
death
SEPEC diseases
pyrexia
depression
weakness
hypothermia
prostration
meningitis
pneumonia
arthritis
diarrhea
what is APEC
animals affected and type of disease
avian pathogenic e coli
systemic disease of birds and poultry
APEC virulence
type I (FI) and P fimbriae
LPS
serum resistance
aerobactin iron uptake
APEC diseases
septicemia
egg yolk peritonitis
penumonia
airsacculitis
salpingitis
what is UPEC
zoonosis?
what does it cause
uropathogenic e coli
zoonotic potential
UTI – cystitis, pyelonephritis
UPEC virulence
type I pili attachment
hemolysin A
LPS
CNF-1 – inflammaotry response
aerobactin, capsule – survival in blood
intracellular bacterial communities
quiescent intracellular reservoirs
UPEC – males or females more susceptible, why
females more susceptible
bacteria enter through urethra
males have long urethra – bacteria don’t reach bladder as easily
UPEC diseases
cystitis, pyelonephritis, pyometra, prostatitis
what is MPEC
what does it cause
how is it caused
mammary pathogenic e coli
casues mastitis
casued by fecal contamiantion of mammary gland through teat sphincter relaxation
MPEC symptoms
udder swelling, pain, and redness
reduced milk production and quality
MPEC treatment
mild mastitis cured without treatment
when systemic – requires treatment
blood agar
macconkey agar
EMB
chromogenic agar
hemolytic on blood agar
pink colonies on macconkey
metallic sheen on EMB
dark blue on chromogenic agar
IVMiC test
indole positive
methyl red positive
voges proskauer negative
citrate negative
molecular typing
MLST
PFGE
RAPD
identification
ETEC – ELISA, PCR, latex agglutination
EPEC – urease +, PCR, effacement of mucosal surface
STEC – edema, bloody diarrhea, hemolytic on blood agar, serotype
SEPEC – isolation from blood, PCR (serum resistance)
UPEC – isolation from urine, type I pili
treatment
rehydration
antibiotics – test for susceptibility
control
colostrum after birth
reduced stress at weaning
hygiene
vaccines
ETEC summary
intestinal e coli
fimbriae, enterotoxins
newborn calves, lambs, piglets
watery diarrhea
neonatal diarrhea, post weaning diarrhea
EPEC summary
intestinal e coli
intimin, T3SS
newborn calves, lambs, pigments
watery diarrhea
post weaning diarrhea
EHEC (STEC/VTEC) summary
intestinal e coli
intimin. T3SS, shiga toxin
bloody diarrhea
edema disease
EIEC (shigella) sumamry
intestinal e coli
invasion
humans
bloody diarrhea, dysentery
ExPEC summary
extraintestinal e coli
serum resistance, aerobactin, type I and P fimbriae, hemolysin, CNF1
newborn calves, lambs, piglets, poultry, dogs, cows, sows
septicemia, systemic infection
colisepticemia, UTI, mastitis
