BBB - Saxitoxin Structure
Bad Bug Book:
Foodborne Pathogenic Microorganisms and Natural Toxins Handbook
Saxitoxin
Bad Bug Book 2nd Edition: Shellfish toxins (PSP, DSP, NSP, ASP, AZP)
Molecular structure of saxitoxin groups: carbamates (most potent), decarbamoyl toxins (intermediate in toxicity; usually present in shellfish but not toxigenic algae), N-sulfocarbamoyl toxins (less potent), and hydroxybenzoate toxins (more recently recognized group of PSP toxins, shown to be specific to the dinoflagellate Gymnodinium catenatum). Toxins in the saxitoxin family may be produced by a range of dinoflagellates, including species in the genera Alexandrium, Gymnodinium, and Pyrodinium. There are also reports of STXs being produced by certain freshwater and brackish cyanobacteria as well as calcareous red macro algae. The traditional route of exposure is accumulation in filter-feeding shellfish.
R1 | R2 | R3 | Carbamate Toxins |
Decarbamoyl Toxins |
N-sulfocarbamoyl Toxins |
Hydroxybenzoate Toxins |
---|---|---|---|---|---|---|
H | H | H | STX | dc-STX | B1 | GC3 |
OH | H | H | NEO | dc-NEO | B2 | |
OH | H | OSO3- | GTX 1 | dc-GTX 1 | C3 | |
H | H | OSO3- | GTX 2 | dc-GTX 2 | C1 | GC1 |
H | OSO3- | H | GTX 3 | dc-GTX 3 | C2 | GC2 |
OH | OSO3- | H | GTX 4 | dc-GTX 4 | C4 | |
R4: |
R4: |
R4: |
R4: |