Test 2 Gram (-) Bacteria Flashcards
All gram negative bacteria have this endotoxin
Lipid A Endotoxin
Enterobacteriaceae include which 3 coliform (lactose + )bacterias?
- E.coli*
- Klebsiella*
- Enterobacter*
Vitamin K production is a benefit of this family of residential bacteria
Enterobacteriaceae
These species of bacteria are the
most common nosocomial infections/ Health care associated infections in ICU patients and effect the
Blood stream, urinary tract, respiratory tract
- Klebsiella*
- Enterobacter*
- Proteus*
The complete antigenic formulation of an organism
Serotype
O: O antigen
H: Flagella
F: Fimbriae
K: Capsule
detection of a specific toxic activity, virulence factor or virulence gene
Virotyping
How are strains of *E. coli *identified?
Serotyping
Capsule
Fimbrial adhesins
Non-fimbrial adhesins
Endotoxins
are all _______ virulence factors
and vary by strain
cell-associated
Enterotoxins
Cytotoxins
Siderophores
are all ______ virulence factors
and vary by strain
extracellular
the most frequent bacterium isolated from clinical samples in human and veterinary medicine
E.coli
What causes Edema Disease in Weaned Piglets?
Shigatoxigenic E. coli
What is the mechanism of action of
Shigatoxigenic E. coli
in weaned piglets?
Inhibit protein synthesis by interacting with 60s ribosmes
How do you Dx an enteric disease?
With a FECAL sample
In E. coli, edema markedly expands the colonic _____ ______,
separating glands.
Even at low magnification, the _____ ______ ______ of colonic epithelium
is prominently basophilic
In E. coli, edema markedly expands the colonic lamina propria,
separating glands.
Even at low magnification, the apical brush border of colonic epithelium
is prominently basophilic
Ultrastructurally, _____
attach to the microvillar border with formation of characteristic
“cups and pedestals”
E.coli
Which antimicrobials are *E. coli *resistant to?
Penicillin
Trimethoprim
Tetracycline
Aminoglycosides
Fluoroquinolones
J5 strains are used in the vaccine for this disease caused by E. coli
Coliform mastitis
The most common bacterial isolate from non-human primates with pneumonia is
Klebsiella pneumoniae
This *Klebsiella *related illness is commonly seen in
foals that have failed to acquire passive transfer via colostrum
Naval Ill
17-year-old male rhesus macaque the animal presented acutely
with coughing and hemoptysis and was sedated for evaluation.
The animal was in thin body condition with pale mucous membranes.
Lung sounds were judged to be harsh but heart sounds were normal. Radiographs revealed consolidation of the left lung field and aerophagia of the esophagus and stomach.
Within the cranial left thoracic cavity, there was a small amount of thin, serosanguineous fluid.
The left lung lobes were consolidated and diffusely and firmly adhered to the pleural wall.
Inflammatory nodules efface 50% of the lung. Inflammatory exudate fills alveoli and airways within these areas; numerous vessels contain large fibrin clots
Alveoli contain abundant viable and degenerate neutrophils, foamy macrophages, and innumerable intra- and extracellular 2-3 µm bacilli that are separated and surrounded by a clear capsule
What is the disease?
*Klebsiella pneumoniae. *
capsular serotypes (K1 and K2) that carry genes MagA (mucoviscosity-associated gene/K1 specific capsular polymerase gene) and
rmpA (regulator of mucoid phenotype)
which make this bacteria more invasive and more resistant to phagocytosis.
Klebsiella pneumoniae
• In humans, HMV infection (a hypomucoviscous variant of Klebsiella pneumoniae)
is unusual in that it infects______ ________and causes
liver abscesses, pneumonia, meningitis, and endophthalmitis.
healthy individuals
What is the infectious dose of Shigella?
LOW!
10 -100 organisms only
In Shigella
Ability to enter epithelial cells and cause disease is mediated by chromosomal genes and virulence genes
coded on a large ___ ____ (220 kb) and Type 3 Secretion System
Virulence Plasmid
This bacteria may cause
**necrohemorrhagic periodontitis/gingivitis **and arthritis
Shigella
Possible sequela of infection by *Shigella *
Intussusception
Rectal Prolapse
___________________
are complex bacterial structures that provide
gram negative pathogens with a unique virulence mechanism
enabling them to inject bacterial effector proteins
directly into the host cell cytoplasm,
bypassing the extracellular environment
Type III secretion systems (T3SSs)
Programmed cell death occurring during Salmonella infection associated with response to pathogen and inflammation
Pyroptosis
The most common infectious diarrheal disease in horses is caused by
- Salmonella *
- Tx: Broad-spectrum antibiotics*
- young birds: unabsorbed yolk sacs and classic gray nodules in the liver, spleen, lungs, heart, gizzard, and intestine.
- Firm, cheesy material in the ceca (cecal cores) and raised plaques in the mucosa of the lower intestine
- Salmonella pullorum*
- Salmonella gallirum*
One of the most common serotypes of Salmonella bacteria reported worldwide.
• SE can be inside perfectly normal-appearing eggs
Eating raw or undercooked eggs = infection
Salmonella serotype Enteritidis (SE)
Pathogenesis involves:
- flea proventricular blockage - early intracellular survival in mammals - late extracellular multiplication with antiinflammatory and toxic effects.
Yersinia pestis
Cell Wall • Rough phenotype (no O-antigen)
Yersinia pestis
Bubonic plague
Yersinia pestis
Plasminogen activator
• Coagulase, fibrinolytic and C3 degradative activity at 37C
YMT mouse toxin
Yersinia pestis
• Worldwide (cold months) • In birds and rodent associated with: • Mesenteric lymphadenitis • Terminal ileitis • Acute gastroenteritis • Septicemia Occasionally in domestic animals and primates • Cats (adult, rural, outdoor)
Yersinia pseudotuberculosis
• Infections of intestine, abdominal lymph nodes, liver, spleen and septicemia • Infection may be self-limiting in immunocompetent hosts • Infection of enterocytes causes diarrhea due to chloride and water secretion following activation of signaling pathways similar to Salmonella • Mastitis in cattle • Abortion in Ruminants and monkeys • Characteristic necrotic foci contain many intralesional bacteria
Yersinia pseudotuberculosis
Mainly in domestic animals and primates • Mesenteric lymphadenitis • Terminal ileitis • Acute gastroenteritis • Septicemia • 34 O-antigen and 20 H-antigen serogroups • 5 byotipes
Yersinia enterocolitica
Yst (Yersinia stable toxin) Chromosomally encoded enterotoxin Deregulation of cGMP Similar to the E. coli ST enterotoxin Opens chloride channels with flow of ions and water to the lumen Blockage of sodium and chloride absorption
Y. enterolcoiiticca
Enteric red-mouth disease • Systemic bacterial Illness of salmonids • Intensively cultured rainbow trout in warm waters • Hemorrhagic inflammation of organs perioral subcutis • Significant mortalities
Yersinia ruckeri
