Roszman 4-21, 23 Microbial and Autoimmune Flashcards
What are 4 characteristics does the Staph bacteria show
cocci (round), gram-positive, coagulase-producing, aerobic/facultative anaerobic, immune-evasive
How does penicillin work
beta lactam group covalently binds transpeptidase disallowing crosslinking in the peptidoglycan so cell is unable to make cell wall, loses osmolarity
What is the difference between gram positive and gram negative bacteria
gram positive lack an outer lipopolysaccharide (LPS). LPS=gram negative (pink)
nosocomial
person-to-person
what is the gene that allows penicillin/methicillin resistance
mecA- coding for PBP2a- a transpeptidase without the interacting residue in the penicillin- inhibited transpeptidase
defect of Lupus Erythematosis
Antibodies made against nuclear proteins, complexing of Ab’s
defect of hemolytic anemia
Abs made against surface groups of RBCs (like Rh)
defect of Myasthenia gravis
Ab’s made against NMJ neurotransmitter ACh
virulence
assumes pathogenicity, describes degree of pathogenicity
invasiveness
ability to invade tissues d(escribes colonization, secrete chemicals that aid invasion, evasiveness to host defences)
toxigenesis
degree of endo (contained in the LPS: gram-neg. trait) or exotoxin production
S. aureus usually resides where in humans
skin, mucous membranes (assymptomatically colonizes in 20-30% humans)
3 diseases caused by S. aureus
folliculitis, abscesses/boils/pimples, pneumonia, meningitis, sepsis, food poisoning
MSCRAMM
means of S. aureus invasion of epithelial cells- endotoxins called Microbial Surface Components Recognizing Adhesive Matrix Molecules ex: Clumping Factor B, Teichoic Acid
Type II autoimmune diseases
Ab’s are against surface or matrix proteins. Ex: myasthenia gravis, hemolytic anemia
