Pfiesteria (Algal Blooms)

Question 1

Eutrophication

Answer 1

excess nitrogen and phosphorus in lakes due to run-off

Question 2

Toxic algal blooms bacteria

Answer 2

cyanobacteria (blue-green algae)

toxic, photosynthetic bacteria (mostly fresh water)

Question 3

toxic protozoa

Answer 3

diatoms: amnesic shellfish poisoning
dinoflagellates: red tide

Question 4

cyanobacteria

Answer 4

blue-green algae
photosynthetic bacteria
endosymbionts
cyanotoxins

Question 5

What toxin is produced by cyanobacteria?

Answer 5

BMAA neurotoxin

Question 6

BMAA neurotoxin mechanism

Answer 6

Can be misincorporated into nascent proteins in place of L-serine, possibly causing protein misfolding and aggregation.
Binding activity of BMAA inhibited in the presence of excess L-serine

Question 7

What is pseudo-nitzschia associated with?

Answer 7

Amnesic Shellfish Poisoning

Question 8

What does pseudo nitzschia produce?

Answer 8

domoic acid = amnestic toxin

Question 9

How does domoic acid damage neurons

Answer 9

neurotoxin analogue of glutamate, damages neurons through influx of Ca2+; causing short-term memory loss

Question 10

What makes red tide?

Answer 10

Karenia brevis

Question 11

What toxin does Karenia brevis make?

Answer 11

Brevetoxins

Question 12

what do brevetoxins cause?

Answer 12

gastroenteritis and respiratory symptoms

Question 13

What disease is associated with brevetoxins?

Answer 13

Neurotoxic Shellfish Poisoning (NSP)

Question 14

The genera Gambierdiscus and Prorocentrum cause what disease?

Answer 14

Ciguatera Fish Poisoning (CFP)

Question 15

Ciguatoxin exposure symptoms

Answer 15

causes gastro, neuro and cardio problems

Question 16

The genera Diophysis causes what disease?

Answer 16

Diarrhetic shellfish poisoning (DSP)

Question 17

What toxin does Diophysis make?

Answer 17

okadaic acid

Question 18

The generas Alexandrium and Gymnodinium cause what disease?

Answer 18

Paralytic Shellfish Poisoning (PSP)

Question 19

what toxin class does alexandrium and gymnodinium make?

Answer 19

saxitoxins

Question 20

What are the major algal toxin associated diseases on the east coast? (3)

Answer 20

Neurotoxic shellfish poisoning, ciguatera fish poisoning, and pfiesteria complex

Question 21

Where is Pfiesteria piscicida found?

Answer 21

mid-atlantic and SE USA

Question 22

What does Pfiesteria cause? (primarily)

Answer 22

massive fish kills with lesions

Question 23

How is Pfiesteria transmitted to humans?

Answer 23

through water exposure

Question 24

Where/When was Pfiesteria first discovered?

Answer 24

During the middle of an outbreak (1991-1997) in 1992 on the Pamlico and Neuse Rivers in North Carolina. Primarily on the Neuse River

Question 25

Where else has Pfiesteria been found?

Answer 25

Maryland – Potomac River

Question 26

Pfiesteria lab exposure symptoms:(6)

Answer 26

respiratory and eye irritation 
skin rashes
gastroenteritis 
cognition deficits
personality changes

Question 27

Pfiesteria acute env. exposure symptoms:

Answer 27

respiratory and eye irritation, headaches, and/or sore throat within 4 hours of exposure

Question 28

What induces the growth of non-toxic Pfiesteria?

Answer 28

agricultural waste

Question 29

what is needed in the environment to induce toxicity in zoospores?

Answer 29

presence of fish induce toxicity in zoospores

Fish-induced amoeboid and cyst stages to become zoospores that then become toxic

Question 30

What is the effect of Pfiesteria toxin(s) on fish?

Answer 30

paralyze fish, disrupt osmotic balance, cause tissue damage, death

Question 31

What are some of the current Pfiesteria research outcomes?

Answer 31

controversial life cycle (Axenic)
Toxicity disputed
rapid PCR diagnostic developed
Environmental reforms - improved disposal of ag waste

Question 32

What species is most prevalent in Florida?

Answer 32

Karenia brevis