Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
|
Diptheria, cholera, and tetanus are exclusively the cause of disease T/F?
|
TRUE;
|
|
|
In large amounts, what can LPS cause (endotoxin)?
|
shock and DIC
|
|
|
T/F exotoxins are all outside the cell and are actively pumped out?
|
FALSE; some are left inside and leave only when cell dies
|
|
|
Where are most gene toxins for exotoxins are found?
|
mobile elements (phages, plasmids, transposons);;;cholera is on a phage
|
|
|
What is the A part of the toxin structure?
|
enzymatic activity
|
|
|
What is the B part of the toxin structure?
|
Cell binding component
|
|
|
What kind of toxins are evident when holes are present on blood agar?
|
hemolysins
|
|
|
what do superantigens do?
|
stimulate an excessive amount of cytokines
|
|
|
What are examples of superantigens?
|
erythrogenic toxins (streptococcus pyogenes); enterotoxins (S.aureus); Toxic shock (Staph. Areus)
|
|
|
How is protein synthesis shut down in Diptheria toxin and Exotoxin A (pseudomonas aeruginosa)?
|
Moving ADP to histidine on EF-2 preventing elongation factor needed for translation
|
|
|
How do shiga toxins inhibit protein synthesis?
|
remove one particular adenine residue from the 28S RNA of 60S ribosomal subunit
|
|
|
What does shiga toxin result in?
|
hemolytic uremic syndrome (damage endothelial cells in kidney, inhibit protein synthesis)
|
|
|
How do cholera toxin work?
|
ADP ribosyltransferases that stimulate G protein > increase cAMP (adenylate cyclase is ON) in enterocytes> massive diarrhea
|
|
|
What kind of paralysis is caused by botulinum toxin?
|
flaccid paralysis (inhibits release of acetylcholine at myoneural junctions)
|
|
|
What does tetanus do?
|
inhibits release of inhibitory interneurons in th espinal cord (MORE STIMULATION)
|
|
|
What do Tetanus and Botulitunum toxin have in common?
|
both are zinc-dependant endopeptidases that inhibit neurotransmitter release
|
|
|
What toxin can cause pseudomembranous colitis?
|
clostridium difficile cytotoxin
|
|
|
How does clostridium difficile cytotoxin cause pseudomembranous colitis?
|
causes disaggregation of actin filaments by glucosylating RhoA (a small GTP binding protein in enterocytes)
|
|
|
What is the difference between passive and active immunization?
|
passive immunization we get antiodies to quickly treat; active is we get antigen to produce long term memorr
|
|
|
What are toxoids?
|
these are derivatives of toxins that are immunogenic but lack toxicity; used in vaccines
|
|
|
What are immunotoxins?
|
active part of the toxin that kills cells linked to a specific monoclonal antibody (tumor killing)
|
|
|
What are pyrogenic exotoxins?
|
toxins that cause excessive recrutiment of cytokines (bind B subunit of TCR and increase cytokines)
|
|
|
Which toxins have ADP ribosyltransferase activity?
|
Diptheria toxin, exotoxin A (pseudomonas aerigunosa); and Cholera, and E.coli LT
|
|
|
Which toxins inhibit Protein synthesis?
|
Diptheria, exotoxin A (P. Aureginosa), shiga toxins
|
|
|
Which toxins are zinc-dependant endopeptidases?
|
tetanus and botulin
|
|
|
Which toxin glucosylates RhoA?
|
clostridium difficile cytotoxin
|
