Micro Review Flashcards
What is the toxin that is associated with bacillus anthracis?
Anthrax exotoxin: Edema Factor and the Lethal Factor
Describe the edema factor of the anthrax exotoxin
Increases cyclic AMP by activated adenylate cyclase and causes edema and phagocyte dysfunction
Describe the lethal factor of the anthrax exotoxin
Zinc dependent protease that inhibits MAPK signaling and causes apoptosis and multisystem disruption
What are the two toxins that are associated with bordetella pertussis?
Pertussis toxin
Adenylate cyclase toxin
Describe the MOA of the pertussis toxin
Disinhibits adenylate cyclase through ADP-ribosylation and increases cAMP levels
Edema and phagocyte dysfunction
Describe the MPA of the adenylate cyclase toxin that is associated with bordetella pertussis
Adenylate cyclase will increase cAMP levels and cause edema and phagocyte issues
What is the toxin that is associated with clostridium botulinum and what is the MOA?
Botulinum toxin blocks the presynaptic release of ACH at the NMJ
flaccid paralysis
Describe Toxin A of C.Diff
Recruits and activates neutrophils
release of cytokines with mucosal inflammation, fluid loss, and diarrhea
Describe Toxin B of C.Diff
Induces actin depolymerization
mucosal cell death and bowel wall necrosis and pseudomembrane formation
What is the MOA of the shiga toxin that is associated with shigella?
Halts protein systhesis by disabling the 60S ribosomal subunit
intestinal epithelial cell death and diarrhea
What are the two toxins that are associated with strep pyogenes?
Pyrogenic exotoxin
Streptolysin O&S
This strep pyogenes toxin acts as a super antigen including fever and shock
This is associated with scarlet fever and STSS
Pyrogen exotoxin
This strep pyogenes toxin damages erythrocytes membranes and causes beta hemolysis
strep O&S
What are the virulence factors that are associated with E Coli?
Lipopolysaccharide K1 capsule polysaccharide Verotoxin Heat-stable/ heat labile enterotoxins P fimbraiae
What is the mechanisms of the LPS of E Coli? What does this cause?
macrophage activation causes widespread cytokine release
This causes bacteremia and shock
What is the mechanism of K1 capsular polysaccharide and what symptoms does this cause?
Prevents phagocytosis and complement mediated lysis
Neonatal meningitis
What is the mechanism of verotoxin in E Coli?
Inactivates 60S ribosomal subunit halting protein synthesis and cell death
What is the mechanism of heat stable and heat labile enterotoxins?
Promotes fluid and electrolyte secretion from the intestinal epithelium
What is the mechanism of P Fimbriae?
Allows the adhesion to uroepithelium
MOST IMPORTANT
What plates does E. coli grow on?
Blood
MacConkey
Eosin methylene blue (EMB)
ferments lactose and produce colonies that have a distinct green metallic sheen
