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Which form of Bacillus anthracis has spores and how long does it take them to develop?
Non-clinical (2-3 days)
What are the two plasmids in B. anthracis? What do they code for?
pX01= Protective Antigen (PA), Edema Factor (EF), Lethal Factor (LF)
pX02= Carries the capA, capB, and capC genes for capsule synthesis (only observed in clinical)
How Anthrax Works?
- PA binds to anthrax receptor
- Cleavage of PA by host furin proteases (smaller part is released, larger part stays attached)
- PA63 heptamer fors prepore
- LF and/or EF binds to prepore complex (competitive binding)
- Endocytosis into acidic compartment
- PA heptamer forms pore in compartment
- LF and/or EF released into cytosol
What is LF? What does it do?
Zing metalloprotease; cleaves MAP kinase --> Necrosis, hypoxia
What is EF? What does it do?
Adenylate cyclase; increases intracellular cAMP --> Edema
What makes up the B. anthracis capsule?
Stimulates macrophages to release TNF-a, IL-1B, and other cytokines.
Which of the B. anthracis factors is most immunogenic?
LF and EF inhibit?
B. anthracis is usually infects humans who have exposure to animals because it primarily affects _______.
3 types of anthrax?
Which two types have no person-to-person spread?
- 1. Inoculation through exposed skin (95%)
- 2. Ingestation
- 3. Inhalation
No person-to-person spread in Ingestation or Inhalation anthrax
Which form of Bacillus anthracis causes ulcers in mouth or esophagus? What is anothr fact about it?
Ingestion (GI); It is 100% fatal.
Which form of B. anthracis has a prolonged latent period?
Inhalation (spores can remain latent in nasal passages or reach lower airways)
Form of B. anthracis that shows mediastinal widening on chestXR?
Inhalation; Nearly 100% mortality in 3 days
Gram-P or Gram-N?
Spores seen in cultures grown in?
Stain spores with?
- Rods, single or in chains
- Low CO2Malachite green
3 stains for the polypeptide capsule of B. anthracis.
India ink, McFadyean methylene blue, DFA
B. anthracis has what kind of capsule?
Name the other non-polysacharride capusle.
- Strep. Pyogenes = Hylauronic acid
What does B. anthracis' colony look like on blood agar?
What type of hemolysis does it have? Motility
- Ground glass
- No hemolysis, no motility
Treat B. anthracis with?
What is B. anthracis resistant to?
Ciprofloxacin or doxycycline (susceptible to penicillin, doxyclcine, and cipro)
Resistant to sulfonamides and extended-spectrum cephalosporins
B. cereus is opportunistic for:
- Ocular infections
- IV Catheter-related sepsis
B. cereus: Gastroenteritis
Heat-stable, proteolysis-resistant enterotoxin
B. cerus: Gastorenteritis
Bacillus cereus: Ocular Disease (3 toxins)
- Necrotic toxin
- Phospholipase C- lechitinase
B. cereus emetic disease usually comes from?
B. cereus diarrheal disease from?
Contaminated meat, vegetables, or sauces
B. cereus must be cultured from the ____
food! (not the feces)
Prevent B. cereus GI disease with?
Rapid food consumption after cooking; proper refrigeration
Other Bacillus species:
Gastroenteritis, opportunistic, pest control?
- B. mycoides
- B. sterothermophilus
- B. subtilis
- B. thuringiensis
Gram-P or Gram-N?
Can grow in 1-45 C and in high salt
Motile at RT
- Facultative anaerobe'
Which bacteria has end-over-end motility?
Facultative intracellular pathogen
Listeria monocytogenes (macrophages, epithelial cells, cultured fibroblasts)
Leu-rich proteins that interact w/ glycoprotein receptors on host.
L. monocytogenes attaches and enters ____ in _____
Enterocytes in Peyer's Patches
What do the Listeriolysin O and 2 PLC's of L. monocytogenes do?
Lyse phagosome and release bacteria.
What bacteria has ActA?
What does it do?
- L. monocytogenes
- Acta is localized at one pole; coordinates actin assembly
Which type of immunity is important in a L. monocytogenes infection?
CMI (humoral is NOT important)
Disease of early onset L. monocytogenes
Ganulomatosis infantiseptica (transplacental)
What bacteria causes bacteremia in pregnant women?
Bacteria whose hemolysis is enhanced by growing next to S. aureus.
Treat L. monocytogenes with? It has a natural resistance to what?
- Pen or amp (w/ or w/o genatmicin)
- Has a natural resistance to cephalosporins
Word association: Ubiquitous
Gram-P or Gram-N?
Ubiquitous in animals; swine
- Facultative anaerobe
- Erysipeloid: Localized skin infection (w/ raised edge)
E. rhusiopathiae is best prevented by?
Gloves for people at risk (fish handlers, butchers, meat processors, farmers, veterinarians)
Having complex nutritional requirements for growth.
H. influenzae and B. pertussis:
Fastidious Gram-N Bacilli
Nicotinamide adenine dinucleotide (NAD)
Haemophilus influenzae requires what two factors for growth?
X & V
First bacteria to have its genome completely sequenced?
4 Virulence factors of H. influenzae:
- Antiphagocytic capsule
- Endotoxin (LOS)
- Ciliostatic factor: arrests cilia motility in vitro
- IgA Protease
What is NTHi?
Non-typable H. influenzae (lacks the polysaccharide capsule so Abs agains them don't work)
Polysaccharide Conjugate Vaccine stimulates __________ immunity
Common cause of COPD exacerbation?
Which bacteria colonizes the mucosal membranes of the respiratory tract?
Haemophilus aegyptius causes (2 diseases)
- Brazilian Purpuric Fever
Causes chancroids that reemble syphilitic chancer (except these are painful w/ associated lymph node swelling)
Bacteria colonizes ciliated cells of the respiratory mucosa.
3 Stages of Disease in Bordetella Pertussis:
- Cattarrhal 1-2 weeks
- Paroxysmal coughing 2-4 weeks
What is used in the B. pertussis vaccine?
Killed phase I cells
DTP/DTap (What do these letters stand for?)
- D: Diphtheria toxoid
- T: Tetanus toxoid
- P: Whole killed phase I bacterial cells
- ap: Pertussis toxoid, adhesin proteins
How should adults be vaccinated against B. pertussis?
How do you treat B. pertussis?