Yessotoxin 1-desulfoyessotoxin

Yessotoxin and its analogues are disulfonated polyether toxins reported from shellfish from different countries, but a new derivative lacking a 1-sulfated substituent, 1-desulfoyessotoxin (YTX with R =H), has been isolated from mussels from Norway <1998MI235>. Its ESI-MS spectrum showed that this compound is 102 Da smaller than YTX 17, implying that one of the sulfate esters in YTX was desulfonated. The NMR data of 1-desulfoyessotoxin are similar to that of YTX 17 except for the 1-methylenic protons where desulfonation occurred they are shifted to upheld by 0.49ppm and their chemical shifts (3.72 and 3.78ppm) are typical of hydroxymethyl protons. 

Daiguji, M., Satake, M., Ramstad, H., Aune, T, Naoki, H., and Yasumoto, T. 1998. Structure and fluorometric HPLC determination of 1-desulfoyessotoxin, a new yessotoxin analog isolated from mussels from Norway. Nat Toxins 6, 235—239. 

At micromolar concentrations, yessotoxin and di-desulfoyessotoxin caused dissociation of glyc-opholin A, a membranal protein in human erythrocytes, and increased the degree of lysis induced by alamethacin and melittin in these cells [58]. By itself, however, similar concentrations of yessotoxin caused no lysis of mouse erythrocytes [55]. 

Yessotoxin inhibited purihed protein phosphatase 2A with an EC50 of 0.36 mg/mL. This activity is lower than that of the classical protein phosphatase inhibitors (okadaic acid, dinophy-sistoxins) by four orders of magnitude [55], Unlike brevetoxins and ciguatoxins, yessotoxin and di-desulfoyessotoxin do not bind to the voltage-gated sodium channel of synaptosomal membranes from rat brain [62],... 

No macroscopic changes were observed in mice dying after intraperitoneal injection of lethal doses of yessotoxin [67], In contrast, the livers of mice receiving di-desnlfoyessotoxin became swollen and yellow in color within hours of administration of toxic doses [69], Consistent with the color change, an increase in hepatic fat levels was recorded in animals dosed with di-desulfoyessotoxin... 

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