Pathogenicity Study Guide Flashcards
Define pathogenicity
The ability to cause disease
Define virulence
The extent of pathogenicity
Portals of entry examples?
Most frequent ?
-mucous membranes
-skin (largest barrier, can get in through hair follicles & sweat glands)
-parenteral route
-preffered portal of entry -inhaled, ingested, cutaneous’
*anthrax can do all 3
Adherence- what structures do bacteria use to attach to host?
Adhesions/ligands bind to receptors:
-GLYCOCALYX
-FIMBRIAE
-M PROTEIN
Define and understand ID50 / LD50
-ID50: infectious dose for 50% of the test population
-LD50: lethal dose (of a toxin) for 50% of the test population
What are functions of various bacterial exoenzymes- coagulase, kinases, etc.
*Coagulase- coagulates fibrinogen
*Kinases- digest fibrin clots
*Hyaluronidase: hydrolyzes hyaluronic acid (acts as glue)
*Collagenase: hydrolyzes collagen (makes bacteria easier to get into)
*IgA protease: destroy IgA antibodies (usually found in mucous membranes)
What is more potent ?
-endotoxin
-exotoxin
Exotoxins
___________ is heat resistant
___________ is not heat resistant
Endotoxin is heat resistant
Exotoxin is not heat resistant
Exotoxins are mostly gram?
Positive
Endotoxins are gram?
Negative
Exotoxins are made of lipids/proteins?
Proteins
Endotoxins are made of lipids/proteins?
Lipids
What type of toxin does staphylococcus aureus have?
What are characteristics ?
-Superantigen
-cause immune response due to release of cytokines from host cell
-symptoms include: fever, nausea, vomiting, diarrhea, shock & death
What type of toxin does clostridium botulinum have?
What are the characteristics?
*A-B toxin; neurotoxin
-alter cell function by inhibiting protein synthesis
What toxins can cause septic shock?
