Term
| What is Koch's postulate? |
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Definition
| -Its the one where you have to get the bacteria from the sick, culture it, and reinfect, causing the same disease |
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Term
| What is the normal endogenous bacteria of the mouth associated with plaque? |
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Definition
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Term
| What is a fairly normal type of bacteria carried in the resp. tract that can result in pneumonia in AIDS? |
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Definition
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Term
| What is the major bac of colon? |
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Definition
-Bacteroides fragilis
-E. coli is present in much lower numbers |
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Term
| What is the bacteria that maintains the acidic pH of the vagina? What moves in if the pH raises? |
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Definition
-Lactobacillus aerophilus
-Candida overgrowth happens in pH imbalance |
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Term
| What do we call it when there are bac in the blood? |
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Definition
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Term
| What is the diff between sub-clinical/unapparent and latent infections? |
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Definition
-In the subclinical ones we can recover microorganisms, but in the latent ones we cannot
-Either way, there are no symptoms |
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Term
| What are some bacterial adhesion structures? |
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Definition
-Lectins; bind to sugars
-Pili or fimbriae also assist in adherence in gram-
-Lipoteichoic acid in gram+
-M-protein in group streptococcus pyogenes; binds resp. mucosa |
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Term
| What are some (4) examples of facultative intracellular bacteria? How do they present? |
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Definition
-Salmonella (typhoid)
-Mycobacterium
-Tuberculosis
-N. gonorrhea
-They often cause granulomatous diseases
-They can replicate inside or outside of the host cells |
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Term
| Give two obligate intracellular bacteria? |
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Definition
-Ricketsia (typhus)
-Chlamydia (trachoma) |
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Term
| How does the M-protein of S. pyogenes inhibit the immune system? |
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Definition
| -It binds to fibrin and fibronectin forming a coat that sterically hinders compliment from binding |
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Term
| What has the A protein and what is its function? |
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Definition
-Staph aureus has the A protein and its function is as an antiphagocytic surface component
-Specifically it inhibits opsonization by binding to the Fc region of IgG |
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Term
| How do listeria and TB survive once endocytosed? |
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Definition
-Listeria escapes the phagosome before fusion with lysosome
-TB inhibits phagosome-lysosome fusion (lives in phagosome) |
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Term
| What is one other method to avoiding death intracellularly? |
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Definition
-Can simply be resistant to the lysosomal enzymes and live in the phagolysosome
-This is the strategy of M. leprae, Leishmania, Salmonella spp, and a few others |
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Term
| What is IgA1 protease? Who uses it? |
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Definition
-It cleaves IgA at the site of entry into mucosa
-Neisseria, Haemophilus influenzae type b, and streptococcus pneumoniae all use it |
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Term
| What is the difference between antigenic variation and modulation? |
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Definition
-Variation happens at a genetic level
-Modulation is reversible change according to environment |
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Term
| What is endotoxin? What does it bind to? |
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Definition
-LPS
-It binds to CD14 and TLR4 on Macs causing TNF-alpha secretion
-See Kaplan notes for complete discussion |
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Term
| What are the two main kinds of exotoxins? |
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Definition
-Ones made of A (active) and B (binding) subunits
-Cytotoxins/cytolysins |
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Term
| What are specific examples of cytolysins? |
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Definition
Alpha-toxin possessed by both;
-C. perfringens; acts as lecithinase
-S. aureus; acts to form pores
-Hemolysins and leukocidins are other examples |
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Term
| What is the shiga toxin? How does it act? What is a similar toxin? |
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Definition
-It interferes with 60S subunit at EF-2
-Produced by Shigella dysenteriae
-It is a type of A-B dimeric toxin
-Shiga-like toxin or *verotoxin is produced by enterohemorhagic E. coli and acts in the same manner |
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Term
| What are some super antigens? |
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Definition
-Toxic shock syndrome toxin (TSST) produced by Staph aureus
-Exotoxin A produced by Strep pyogenes |
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Term
| What is the action of streptokinase? Of coagulase? |
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Definition
-It activates plasminogen to promote fibrinolysis
-Coagulase basically does the opposite, activating thrombin
-It is produced by S. aureus and acts to protect the bac |
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Term
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Definition
| -They acquire iron for the bacteria |
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Term
| Note; her toxin discussion is weak sauce. See Kaplan cards for better picture. |
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Definition
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