1 a) Exotoxins

Question 1

exotoxins are

Answer 1

heatlabile (sensitive) proteins. very toxic. antigenic therefore used to make toxoids (toxin like but not toxic) to be used in vaccines (like tetanus toxoid)

Question 2

AB exotoxins

Answer 2

some exotoxins composed of 2 diff types of subunits. B subunit binds to specific host cell receptor. A is the toxic part and has enzymatic fn

Question 3

C. diptheria exotoxin causes

Answer 3

organ damage and death

Question 4

C. diptheria AB exotoxin details

Answer 4

B subunit binds to specific growth factor receptor present on some tissues. exotoxin taken up by endocytosis. pH in endosome separates AB subunits. A is released into cytoplasm where it catalyses ADP ribosylation of elongation factor 2 (used in protein synthesis)

Question 5

NAD⁺ + EF2 —>ADP-ribosyl-EF2 + nicotinamide does what

Answer 5

inactivates EF2, cell dies b/c protein synthesis stops

Question 6

C. diptheria exotoxin is encoded by a

Answer 6

lysogenic phage