Microbiology Flashcards
how does the skin protect itself from microorganisms?
it produces sebum inhibiting bacterial growth
dry skin desiccates organisms
competitive bacterial flora
examples of competitive bacterial flora
staph epidermidis
corynebacterium
propionibacterium
five virulence factors
adhesin invasin impedin aggressin modulin
define adhesin
enables binding of the organism to the host tissue
define invasin
enables organism to invade host cell/tissue
define impedin
enables organism to avoid host defence mechanisms
define aggressin
causes damage to the host directly
define modulin
causes damage to the host indirectly
do some people carry staph aureus on their skin?
yes
virulence factors of staph aureus
fibrinogen binding protein leucocidin (exotoxin that kills leucocytes) enterotoxin (food poisoning) TSST-1 coagulase positive (clots plasma) PVL
what is TSST-1
superantigen that produces toxins
what does TSST-1 cause?
vomiting
fever
scalded skin syndrome
toxic shock syndrome
how does TSST-1 cause damage
massive release of cytokines
describe PVL (Panton-Valentine-Leukocidin)
this is a toxin produced by a certain strain of staph aureus that kills leucocytes
what does PVL cause
furunculosis
necrotising pneumonia
necrotising fasciitis
antibiotic of choice for staph aureus
flucloxacillin