Module 10

Question 1

Toxins

Answer 1

small molecules produced by living organisms that are poisonous to other species, can be molecule/peptide/protein toxin

Question 2

Molecule

Answer 2

Saxitoxin

Question 3

Peptide toxins

Answer 3

fungus, segments cut out of pre-protein, then modified to create toxin

Question 4

Protein toxin

Answer 4

staphylococcal enterotoxin B (food poisoning), cross-links T cells inducing over-inflammatory response

Question 5

Categories

Answer 5

A (botulinum), B (ricin, staphylococcal enterotoxin B, clostridium perfringens E

Question 6

Testing

Answer 6

not living so can’t use PCR or DNA based methods, instead antibody-bsaed methods

Question 7

Ricin

Answer 7

• Casstor beans
• LD50 = 3-15 ug/kg
• ID source plant via contaminating DNA in toxin preparation
• Castor oil is everywhere – the leftover is cake aka the toxin
• Heterodimeric glycoprotein: A chain (action, inhibits protein synthesis) and B chain (transport, facilitates entry into cell)

Question 8

ELISA (ricin)

Answer 8

• Indirect: antigen + antibody + substrate
• Sandwiched: antibody + antigen + antibody

Question 9

MS (Ricin)

Answer 9

• Leads to source, accurate, but doesn’t not determine if active
• Looking for DNA fragments to link to source (best = nuclear SNPs)

Question 10

Botulinum

Answer 10

• LD50 = as low as 0.090-0.15 ug/kg for intravenous
• Types = foodborne, wound, intestinal, inadvertent, intentional
• Positive uses = overactive muscle conditions, PT brain injury, post-stroke spasticity, BOTOX

Question 11

Bacteriology (botulinum)

Answer 11

• A/B/E/F = naturally occurring
• Group 1: proteolytic, A/~B/~F
• Group 2: not proteolytic, E/~/B/~F
• Group 3: C (avian) and D (cattle)
• Group 4: Argentina

Question 12

BoNT

Answer 12

• 900 kDa protein complex (Massive)
• NT = 150 kDa with heavy chain (serotype) and light chain (damage) subunits
• LC targets SNARE so neurotransmitters can no longer be released